v2.5.0

changelog.md

@@ -1,5 +1,48 @@
 # Changelog
 
+## 2025-11-27 - 2.5.0 - feat(pypi,rubygems)
+Add PyPI and RubyGems protocol implementations, upstream caching, and auth/storage improvements
+
+- Implemented full PyPI support (PEP 503 Simple API HTML, PEP 691 JSON API, legacy upload handling, name normalization, hash verification, content negotiation, package/file storage and metadata management).
+- Implemented RubyGems support (compact index, /versions, /info, /names endpoints, gem upload, yank/unyank, platform handling and file storage).
+- Expanded RegistryStorage with protocol-specific helpers for OCI, NPM, Maven, Cargo, Composer, PyPI, and RubyGems (get/put/delete/list helpers, metadata handling, context-aware hooks).
+- Added AuthManager and DefaultAuthProvider improvements: unified token creation/validation for multiple protocols (npm, oci, maven, composer, cargo, pypi, rubygems) and OCI JWT support.
+- Added upstream infrastructure: BaseUpstream, UpstreamCache (S3-backed optional, stale-while-revalidate, negative caching), circuit breaker with retries/backoff and resilience defaults.
+- Added various protocol registries (NPM, Maven, Cargo, OCI, PyPI) with request routing, permission checks, and optional upstream proxying/caching.
+
+## 2025-11-27 - 2.4.0 - feat(core)
+Add pluggable auth providers, storage hooks, multi-upstream cache awareness, and PyPI/RubyGems protocol implementations
+
+- Introduce pluggable authentication: IAuthProvider interface and DefaultAuthProvider (in-memory) with OCI JWT support and UUID tokens.
+- AuthManager now accepts a custom provider and delegates all auth operations (authenticate, validateToken, create/revoke tokens, authorize, listUserTokens).
+- Add storage hooks (IStorageHooks) and hook contexts: beforePut/afterPut/afterGet/beforeDelete/afterDelete. RegistryStorage now supports hooks, context management (setContext/withContext) and invokes hooks around operations.
+- RegistryStorage expanded with many protocol-specific helper methods (OCI, NPM, Maven, Cargo, Composer, PyPI, RubyGems) and improved S3/SmartBucket integration.
+- Upstream improvements: BaseUpstream and UpstreamCache became multi-upstream aware (cache keys now include upstream URL), cache operations are async and support negative caching, stale-while-revalidate, ETag/metadata persistence, and S3-backed storage layer.
+- Circuit breaker, retry, resilience and scope-rule routing enhancements for upstreams; upstream fetch logic updated to prefer primary upstream for cache keys and background revalidation behavior.
+- SmartRegistry API extended to accept custom authProvider and storageHooks, and now wires RegistryStorage and AuthManager with those options. Core exports updated to expose auth and storage interfaces and DefaultAuthProvider.
+- Add full PyPI (PEP 503/691, upload API) and RubyGems (Compact Index, API v1, uploads/yank/unyank, specs endpoints) registry implementations with parsing, upload/download, metadata management and upstream proxying.
+- Add utility helpers: binary buffer helpers (toBuffer/isBinaryData), pypi and rubygems helper modules, and numerous protocol-specific helpers and tests referenced in readme.hints.
+- These changes are additive and designed to be backward compatible; bumping minor version.
+
+## 2025-11-27 - 2.3.0 - feat(upstream)
+Add upstream proxy/cache subsystem and integrate per-protocol upstreams
+
+- Introduce a complete upstream subsystem (BaseUpstream, UpstreamCache, CircuitBreaker) with caching, negative-cache, stale-while-revalidate, retries, exponential backoff and per-upstream circuit breakers.
+- Add upstream interfaces and defaults (ts/upstream/interfaces.upstream.ts) and export upstream utilities from ts/upstream/index.ts and root ts/index.ts.
+- Implement protocol-specific upstream clients for npm, pypi, maven, composer, cargo and rubygems (classes.*upstream.ts) to fetch metadata and artifacts from configured upstream registries.
+- Integrate upstream usage into registries: registries now accept an upstream config, attempt to fetch missing metadata/artifacts from upstreams, cache results locally, and expose destroy() to stop upstream resources.
+- Add SmartRequest and minimatch to dependencies and expose smartrequest/minimatch via ts/plugins.ts for HTTP requests and glob-based scope matching.
+- Update package.json to add @push.rocks/smartrequest and minimatch dependencies.
+- Various registry implementations updated to utilize upstreams (npm, pypi, maven, composer, cargo, rubygems, oci) including URL rewrites and caching behavior.
+
+## 2025-11-27 - 2.2.3 - fix(tests)
+Use unique test run IDs and add S3 cleanup in test helpers to avoid cross-run conflicts
+
+- Add generateTestRunId() helper in test/helpers/registry.ts to produce unique IDs for each test run
+- Update PyPI and Composer native CLI tests to use generated testPackageName / unauth-pkg-<id> to avoid package name collisions between runs
+- Import smartbucket and add S3 bucket cleanup logic in test helpers to remove leftover objects between test runs
+- Improve test robustness by skipping upload-dependent checks when tools (twine/composer) are not available and logging outputs for debugging
+
 ## 2025-11-25 - 2.2.2 - fix(npm)
 Replace console logging with structured Smartlog in NPM registry and silence RubyGems helper error logging
 

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@push.rocks/smartregistry",
-  "version": "2.2.2",
+  "version": "2.5.0",
   "private": false,
   "description": "A composable TypeScript library implementing OCI, NPM, Maven, Cargo, Composer, PyPI, and RubyGems registries for building unified container and package registries",
   "main": "dist_ts/index.js",
@@ -50,8 +50,10 @@
     "@push.rocks/smartbucket": "^4.3.0",
     "@push.rocks/smartlog": "^3.1.10",
     "@push.rocks/smartpath": "^6.0.0",
+    "@push.rocks/smartrequest": "^5.0.1",
     "@tsclass/tsclass": "^9.3.0",
-    "adm-zip": "^0.5.10"
+    "adm-zip": "^0.5.10",
+    "minimatch": "^10.1.1"
   },
   "packageManager": "pnpm@10.18.1+sha512.77a884a165cbba2d8d1c19e3b4880eee6d2fcabd0d879121e282196b80042351d5eb3ca0935fa599da1dc51265cc68816ad2bddd2a2de5ea9fdf92adbec7cd34"
 }

pnpm-lock.yaml

@@ -20,12 +20,18 @@ importers:
       '@push.rocks/smartpath':
         specifier: ^6.0.0
         version: 6.0.0
+      '@push.rocks/smartrequest':
+        specifier: ^5.0.1
+        version: 5.0.1
       '@tsclass/tsclass':
         specifier: ^9.3.0
         version: 9.3.0
       adm-zip:
         specifier: ^0.5.10
         version: 0.5.16
+      minimatch:
+        specifier: ^10.1.1
+        version: 10.1.1
     devDependencies:
       '@git.zone/tsbuild':
         specifier: ^3.1.0

readme.md

@@ -4,7 +4,7 @@
 
 ## Issue Reporting and Security
 
-For reporting bugs, issues, or security vulnerabilities, please visit [community.foss.global/](https://community.foss.global/). This is the central community hub for all issue reporting. Developers who want to sign a contribution agreement and go through identification can also get a [code.foss.global/](https://code.foss.global/) account to submit Pull Requests directly.
+For reporting bugs, issues, or security vulnerabilities, please visit [community.foss.global/](https://community.foss.global/). This is the central community hub for all issue reporting. Developers who sign and comply with our contribution agreement and go through identification can also get a [code.foss.global/](https://code.foss.global/) account to submit Pull Requests directly.
 
 ## ✨ Features
 
@@ -82,6 +82,19 @@ For reporting bugs, issues, or security vulnerabilities, please visit [community
 - ✅ Dependency resolution
 - ✅ Legacy API compatibility
 
+### 🌐 Upstream Proxy & Caching
+- **Multi-Upstream Support**: Configure multiple upstream registries per protocol with priority ordering
+- **Scope-Based Routing**: Route specific packages/scopes to different upstreams (e.g., `@company/*` → private registry)
+- **S3-Backed Cache**: Persistent caching using existing S3 storage with URL-based cache paths
+- **Circuit Breaker**: Automatic failover with configurable thresholds
+- **Stale-While-Revalidate**: Serve cached content while refreshing in background
+- **Content-Aware TTLs**: Different TTLs for immutable (tarballs) vs mutable (metadata) content
+
+### 🔌 Enterprise Extensibility
+- **Pluggable Auth Provider** (`IAuthProvider`): Integrate LDAP, OAuth, SSO, or custom auth systems
+- **Storage Event Hooks** (`IStorageHooks`): Quota tracking, audit logging, virus scanning, cache invalidation
+- **Request Actor Context**: Pass user/org info through requests for audit trails and rate limiting
+
 ## 📥 Installation
 
 ```bash
@@ -648,6 +661,217 @@ const canWrite = await authManager.authorize(
 );
 ```
 
+### 🌐 Upstream Proxy Configuration
+
+```typescript
+import { SmartRegistry, IRegistryConfig } from '@push.rocks/smartregistry';
+
+const config: IRegistryConfig = {
+  storage: { /* S3 config */ },
+  auth: { /* Auth config */ },
+  npm: {
+    enabled: true,
+    basePath: '/npm',
+    upstream: {
+      enabled: true,
+      upstreams: [
+        {
+          id: 'company-private',
+          name: 'Company Private NPM',
+          url: 'https://npm.internal.company.com',
+          priority: 1,  // Lower = higher priority
+          enabled: true,
+          scopeRules: [
+            { pattern: '@company/*', action: 'include' },
+            { pattern: '@internal/*', action: 'include' },
+          ],
+          auth: { type: 'bearer', token: process.env.NPM_PRIVATE_TOKEN },
+        },
+        {
+          id: 'npmjs',
+          name: 'NPM Public Registry',
+          url: 'https://registry.npmjs.org',
+          priority: 10,
+          enabled: true,
+          scopeRules: [
+            { pattern: '@company/*', action: 'exclude' },
+            { pattern: '@internal/*', action: 'exclude' },
+          ],
+          auth: { type: 'none' },
+          cache: { defaultTtlSeconds: 300 },
+          resilience: { timeoutMs: 30000, maxRetries: 3 },
+        },
+      ],
+      cache: { enabled: true, staleWhileRevalidate: true },
+    },
+  },
+  oci: {
+    enabled: true,
+    basePath: '/oci',
+    upstream: {
+      enabled: true,
+      upstreams: [
+        {
+          id: 'dockerhub',
+          name: 'Docker Hub',
+          url: 'https://registry-1.docker.io',
+          priority: 1,
+          enabled: true,
+          auth: { type: 'none' },
+        },
+        {
+          id: 'ghcr',
+          name: 'GitHub Container Registry',
+          url: 'https://ghcr.io',
+          priority: 2,
+          enabled: true,
+          scopeRules: [{ pattern: 'ghcr.io/*', action: 'include' }],
+          auth: { type: 'bearer', token: process.env.GHCR_TOKEN },
+        },
+      ],
+    },
+  },
+};
+
+const registry = new SmartRegistry(config);
+await registry.init();
+
+// Requests for @company/* packages go to private registry
+// Other packages proxy through to npmjs.org with caching
+```
+
+### 🔌 Custom Auth Provider
+
+```typescript
+import { SmartRegistry, IAuthProvider, IAuthToken, ICredentials, TRegistryProtocol } from '@push.rocks/smartregistry';
+
+// Implement custom auth (e.g., LDAP, OAuth)
+class LdapAuthProvider implements IAuthProvider {
+  constructor(private ldapClient: LdapClient) {}
+
+  async authenticate(credentials: ICredentials): Promise<string | null> {
+    const result = await this.ldapClient.bind(credentials.username, credentials.password);
+    return result.success ? credentials.username : null;
+  }
+
+  async validateToken(token: string, protocol?: TRegistryProtocol): Promise<IAuthToken | null> {
+    const session = await this.sessionStore.get(token);
+    if (!session) return null;
+    return {
+      userId: session.userId,
+      scopes: session.scopes,
+      readonly: session.readonly,
+      created: session.created,
+    };
+  }
+
+  async createToken(userId: string, protocol: TRegistryProtocol, options?: ITokenOptions): Promise<string> {
+    const token = crypto.randomUUID();
+    await this.sessionStore.set(token, { userId, protocol, ...options });
+    return token;
+  }
+
+  async revokeToken(token: string): Promise<void> {
+    await this.sessionStore.delete(token);
+  }
+
+  async authorize(token: IAuthToken | null, resource: string, action: string): Promise<boolean> {
+    if (!token) return action === 'read'; // Anonymous read-only
+    // Check LDAP groups, roles, etc.
+    return this.checkPermissions(token.userId, resource, action);
+  }
+}
+
+// Use custom provider
+const registry = new SmartRegistry({
+  ...config,
+  authProvider: new LdapAuthProvider(ldapClient),
+});
+```
+
+### 📊 Storage Hooks (Quota & Audit)
+
+```typescript
+import { SmartRegistry, IStorageHooks, IStorageHookContext } from '@push.rocks/smartregistry';
+
+const storageHooks: IStorageHooks = {
+  // Block uploads that exceed quota
+  async beforePut(ctx: IStorageHookContext) {
+    if (ctx.actor?.orgId) {
+      const usage = await getStorageUsage(ctx.actor.orgId);
+      const quota = await getQuota(ctx.actor.orgId);
+
+      if (usage + (ctx.metadata?.size || 0) > quota) {
+        return { allowed: false, reason: 'Storage quota exceeded' };
+      }
+    }
+    return { allowed: true };
+  },
+
+  // Update usage tracking after successful upload
+  async afterPut(ctx: IStorageHookContext) {
+    if (ctx.actor?.orgId && ctx.metadata?.size) {
+      await incrementUsage(ctx.actor.orgId, ctx.metadata.size);
+    }
+
+    // Audit log
+    await auditLog.write({
+      action: 'storage.put',
+      key: ctx.key,
+      protocol: ctx.protocol,
+      actor: ctx.actor,
+      timestamp: ctx.timestamp,
+    });
+  },
+
+  // Prevent deletion of protected packages
+  async beforeDelete(ctx: IStorageHookContext) {
+    if (await isProtectedPackage(ctx.key)) {
+      return { allowed: false, reason: 'Cannot delete protected package' };
+    }
+    return { allowed: true };
+  },
+
+  // Log all access for compliance
+  async afterGet(ctx: IStorageHookContext) {
+    await accessLog.write({
+      action: 'storage.get',
+      key: ctx.key,
+      actor: ctx.actor,
+      timestamp: ctx.timestamp,
+    });
+  },
+};
+
+const registry = new SmartRegistry({
+  ...config,
+  storageHooks,
+});
+```
+
+### 👤 Request Actor Context
+
+```typescript
+// Pass actor information through requests for audit/quota tracking
+const response = await registry.handleRequest({
+  method: 'PUT',
+  path: '/npm/my-package',
+  headers: { 'Authorization': 'Bearer <token>' },
+  query: {},
+  body: packageData,
+  actor: {
+    userId: 'user123',
+    tokenId: 'token-abc',
+    ip: req.ip,
+    userAgent: req.headers['user-agent'],
+    orgId: 'org-456',
+    sessionId: 'session-xyz',
+  },
+});
+
+// Actor info is available in storage hooks for quota/audit
+```
+
 ## ⚙️ Configuration
 
 ### Storage Configuration

test/helpers/registry.ts

@@ -1,11 +1,63 @@
 import * as qenv from '@push.rocks/qenv';
 import * as crypto from 'crypto';
 import * as smartarchive from '@push.rocks/smartarchive';
+import * as smartbucket from '@push.rocks/smartbucket';
 import { SmartRegistry } from '../../ts/classes.smartregistry.js';
 import type { IRegistryConfig } from '../../ts/core/interfaces.core.js';
 
 const testQenv = new qenv.Qenv('./', './.nogit');
 
+/**
+ * Clean up S3 bucket contents for a fresh test run
+ * @param prefix Optional prefix to delete (e.g., 'cargo/', 'npm/', 'composer/')
+ */
+/**
+ * Generate a unique test run ID for avoiding conflicts between test runs
+ * Uses timestamp + random suffix for uniqueness
+ */
+export function generateTestRunId(): string {
+  const timestamp = Date.now().toString(36);
+  const random = Math.random().toString(36).substring(2, 6);
+  return `${timestamp}${random}`;
+}
+
+export async function cleanupS3Bucket(prefix?: string): Promise<void> {
+  const s3AccessKey = await testQenv.getEnvVarOnDemand('S3_ACCESSKEY');
+  const s3SecretKey = await testQenv.getEnvVarOnDemand('S3_SECRETKEY');
+  const s3Endpoint = await testQenv.getEnvVarOnDemand('S3_ENDPOINT');
+  const s3Port = await testQenv.getEnvVarOnDemand('S3_PORT');
+
+  const s3 = new smartbucket.SmartBucket({
+    accessKey: s3AccessKey || 'minioadmin',
+    accessSecret: s3SecretKey || 'minioadmin',
+    endpoint: s3Endpoint || 'localhost',
+    port: parseInt(s3Port || '9000', 10),
+    useSsl: false,
+  });
+
+  try {
+    const bucket = await s3.getBucket('test-registry');
+    if (bucket) {
+      if (prefix) {
+        // Delete only objects with the given prefix
+        const files = await bucket.fastList({ prefix });
+        for (const file of files) {
+          await bucket.fastRemove({ path: file.name });
+        }
+      } else {
+        // Delete all objects in the bucket
+        const files = await bucket.fastList({});
+        for (const file of files) {
+          await bucket.fastRemove({ path: file.name });
+        }
+      }
+    }
+  } catch (error) {
+    // Bucket might not exist yet, that's fine
+    console.log('Cleanup: No bucket to clean or error:', error);
+  }
+}
+
 /**
  * Create a test SmartRegistry instance with all protocols enabled
  */

test/test.composer.nativecli.node.ts

@@ -6,7 +6,7 @@
 import { expect, tap } from '@git.zone/tstest/tapbundle';
 import { tapNodeTools } from '@git.zone/tstest/tapbundle_serverside';
 import { SmartRegistry } from '../ts/index.js';
-import { createTestRegistry, createTestTokens, createComposerZip } from './helpers/registry.js';
+import { createTestRegistry, createTestTokens, createComposerZip, generateTestRunId } from './helpers/registry.js';
 import type { IRequestContext, IResponse } from '../ts/core/interfaces.core.js';
 import * as http from 'http';
 import * as url from 'url';
@@ -21,6 +21,11 @@ let registryPort: number;
 let composerToken: string;
 let testDir: string;
 let composerHome: string;
+let hasComposer = false;
+
+// Unique test run ID to avoid conflicts between test runs
+const testRunId = generateTestRunId();
+const testPackageName = `testvendor/test-pkg-${testRunId}`;
 
 /**
  * Create HTTP server wrapper around SmartRegistry
@@ -235,12 +240,11 @@ tap.test('Composer CLI: should verify composer is installed', async () => {
   try {
     const result = await tapNodeTools.runCommand('composer --version');
     console.log('Composer version output:', result.stdout.substring(0, 200));
+    hasComposer = result.exitCode === 0;
     expect(result.exitCode).toEqual(0);
   } catch (error) {
     console.log('Composer CLI not available, skipping native CLI tests');
-    // Skip remaining tests if Composer is not installed
+    hasComposer = false;
-    tap.skip.test('Composer CLI: remaining tests skipped - composer not available');
-    return;
   }
 });
 
@@ -284,27 +288,32 @@ tap.test('Composer CLI: should verify server is responding', async () => {
 });
 
 tap.test('Composer CLI: should upload a package via API', async () => {
-  const vendorPackage = 'testvendor/test-package';
   const version = '1.0.0';
 
-  await uploadComposerPackage(vendorPackage, version, composerToken, registryUrl);
+  await uploadComposerPackage(testPackageName, version, composerToken, registryUrl);
 
-  // Verify package exists via packages.json
+  // Verify package exists via p2 metadata endpoint (more reliable than packages.json for new packages)
-  const response = await fetch(`${registryUrl}/composer/packages.json`);
+  const metadataResponse = await fetch(`${registryUrl}/composer/p2/${testPackageName}.json`);
-  expect(response.status).toEqual(200);
+  expect(metadataResponse.status).toEqual(200);
 
-  const packagesJson = await response.json();
+  const metadata = await metadataResponse.json();
-  expect(packagesJson.packages).toBeDefined();
+  expect(metadata.packages).toBeDefined();
-  expect(packagesJson.packages[vendorPackage]).toBeDefined();
+  expect(metadata.packages[testPackageName]).toBeDefined();
+  expect(metadata.packages[testPackageName].length).toBeGreaterThan(0);
 });
 
 tap.test('Composer CLI: should require package from registry', async () => {
+  if (!hasComposer) {
+    console.log('Skipping - composer not available');
+    return;
+  }
+
   const projectDir = path.join(testDir, 'consumer-project');
   createComposerProject(projectDir, registryUrl);
 
   // Try to require the package we uploaded
   const result = await runComposerCommand(
-    'require testvendor/test-package:1.0.0 --no-interaction',
+    `require ${testPackageName}:1.0.0 --no-interaction`,
     projectDir
   );
   console.log('composer require output:', result.stdout);
@@ -314,8 +323,15 @@ tap.test('Composer CLI: should require package from registry', async () => {
 });
 
 tap.test('Composer CLI: should verify package in vendor directory', async () => {
+  if (!hasComposer) {
+    console.log('Skipping - composer not available');
+    return;
+  }
+
   const projectDir = path.join(testDir, 'consumer-project');
-  const packageDir = path.join(projectDir, 'vendor', 'testvendor', 'test-package');
+  // Parse vendor/package from testPackageName (e.g., "testvendor/test-pkg-abc123")
+  const [vendor, pkg] = testPackageName.split('/');
+  const packageDir = path.join(projectDir, 'vendor', vendor, pkg);
 
   expect(fs.existsSync(packageDir)).toEqual(true);
 
@@ -325,25 +341,36 @@ tap.test('Composer CLI: should verify package in vendor directory', async () =>
 });
 
 tap.test('Composer CLI: should upload second version', async () => {
-  const vendorPackage = 'testvendor/test-package';
   const version = '2.0.0';
 
-  await uploadComposerPackage(vendorPackage, version, composerToken, registryUrl);
+  await uploadComposerPackage(testPackageName, version, composerToken, registryUrl);
 
-  // Verify both versions exist
+  // Verify both versions exist via p2 metadata endpoint (Composer v2 format)
-  const response = await fetch(`${registryUrl}/composer/packages.json`);
+  const response = await fetch(`${registryUrl}/composer/p2/${testPackageName}.json`);
-  const packagesJson = await response.json();
+  expect(response.status).toEqual(200);
 
-  expect(packagesJson.packages[vendorPackage]['1.0.0']).toBeDefined();
+  const metadata = await response.json();
-  expect(packagesJson.packages[vendorPackage]['2.0.0']).toBeDefined();
+  expect(metadata.packages).toBeDefined();
+  expect(metadata.packages[testPackageName]).toBeDefined();
+  // Check that both versions are present
+  const versions = metadata.packages[testPackageName];
+  expect(versions.length).toBeGreaterThanOrEqual(2);
+  const versionNumbers = versions.map((v: any) => v.version);
+  expect(versionNumbers).toContain('1.0.0');
+  expect(versionNumbers).toContain('2.0.0');
 });
 
 tap.test('Composer CLI: should update to new version', async () => {
+  if (!hasComposer) {
+    console.log('Skipping - composer not available');
+    return;
+  }
+
   const projectDir = path.join(testDir, 'consumer-project');
 
   // Update to version 2.0.0
   const result = await runComposerCommand(
-    'require testvendor/test-package:2.0.0 --no-interaction',
+    `require ${testPackageName}:2.0.0 --no-interaction`,
     projectDir
   );
   console.log('composer update output:', result.stdout);
@@ -355,11 +382,16 @@ tap.test('Composer CLI: should update to new version', async () => {
   expect(fs.existsSync(lockPath)).toEqual(true);
 
   const lockContent = JSON.parse(fs.readFileSync(lockPath, 'utf-8'));
-  const pkg = lockContent.packages.find((p: any) => p.name === 'testvendor/test-package');
+  const pkg = lockContent.packages.find((p: any) => p.name === testPackageName);
   expect(pkg?.version).toEqual('2.0.0');
 });
 
 tap.test('Composer CLI: should search for packages', async () => {
+  if (!hasComposer) {
+    console.log('Skipping - composer not available');
+    return;
+  }
+
   const projectDir = path.join(testDir, 'consumer-project');
 
   // Search for packages (may not work on all Composer versions)
@@ -375,23 +407,33 @@ tap.test('Composer CLI: should search for packages', async () => {
 });
 
 tap.test('Composer CLI: should show package info', async () => {
+  if (!hasComposer) {
+    console.log('Skipping - composer not available');
+    return;
+  }
+
   const projectDir = path.join(testDir, 'consumer-project');
 
   const result = await runComposerCommand(
-    'show testvendor/test-package --no-interaction',
+    `show ${testPackageName} --no-interaction`,
     projectDir
   );
   console.log('composer show output:', result.stdout);
 
   expect(result.exitCode).toEqual(0);
-  expect(result.stdout).toContain('testvendor/test-package');
+  expect(result.stdout).toContain(testPackageName);
 });
 
 tap.test('Composer CLI: should remove package', async () => {
+  if (!hasComposer) {
+    console.log('Skipping - composer not available');
+    return;
+  }
+
   const projectDir = path.join(testDir, 'consumer-project');
 
   const result = await runComposerCommand(
-    'remove testvendor/test-package --no-interaction',
+    `remove ${testPackageName} --no-interaction`,
     projectDir
   );
   console.log('composer remove output:', result.stdout);
@@ -399,7 +441,8 @@ tap.test('Composer CLI: should remove package', async () => {
   expect(result.exitCode).toEqual(0);
 
   // Verify package is removed from vendor
-  const packageDir = path.join(projectDir, 'vendor', 'testvendor', 'test-package');
+  const [vendor, pkg] = testPackageName.split('/');
+  const packageDir = path.join(projectDir, 'vendor', vendor, pkg);
   expect(fs.existsSync(packageDir)).toEqual(false);
 });
 

test/test.pypi.nativecli.node.ts

@@ -6,7 +6,7 @@
 import { expect, tap } from '@git.zone/tstest/tapbundle';
 import { tapNodeTools } from '@git.zone/tstest/tapbundle_serverside';
 import { SmartRegistry } from '../ts/index.js';
-import { createTestRegistry, createTestTokens, createPythonWheel, createPythonSdist } from './helpers/registry.js';
+import { createTestRegistry, createTestTokens, createPythonWheel, createPythonSdist, generateTestRunId } from './helpers/registry.js';
 import type { IRequestContext, IResponse } from '../ts/core/interfaces.core.js';
 import * as http from 'http';
 import * as url from 'url';
@@ -24,6 +24,10 @@ let pipHome: string;
 let hasPip = false;
 let hasTwine = false;
 
+// Unique test run ID to avoid conflicts between test runs
+const testRunId = generateTestRunId();
+const testPackageName = `test-pypi-pkg-${testRunId}`;
+
 /**
  * Create HTTP server wrapper around SmartRegistry
  */
@@ -347,9 +351,8 @@ tap.test('PyPI CLI: should upload wheel with twine', async () => {
     return;
   }
 
-  const packageName = 'test-pypi-pkg';
   const version = '1.0.0';
-  const wheelPath = await createTestWheelFile(packageName, version, testDir);
+  const wheelPath = await createTestWheelFile(testPackageName, version, testDir);
 
   expect(fs.existsSync(wheelPath)).toEqual(true);
 
@@ -369,9 +372,7 @@ tap.test('PyPI CLI: should verify package in simple index', async () => {
     return;
   }
 
-  const packageName = 'test-pypi-pkg';
+  const response = await fetch(`${registryUrl}/pypi/simple/${testPackageName}/`);
-
-  const response = await fetch(`${registryUrl}/pypi/simple/${packageName}/`);
   expect(response.status).toEqual(200);
 
   const html = await response.text();
@@ -384,9 +385,8 @@ tap.test('PyPI CLI: should upload sdist with twine', async () => {
     return;
   }
 
-  const packageName = 'test-pypi-pkg';
   const version = '1.1.0';
-  const sdistPath = await createTestSdistFile(packageName, version, testDir);
+  const sdistPath = await createTestSdistFile(testPackageName, version, testDir);
 
   expect(fs.existsSync(sdistPath)).toEqual(true);
 
@@ -406,9 +406,7 @@ tap.test('PyPI CLI: should list all versions in simple index', async () => {
     return;
   }
 
-  const packageName = 'test-pypi-pkg';
+  const response = await fetch(`${registryUrl}/pypi/simple/${testPackageName}/`);
-
-  const response = await fetch(`${registryUrl}/pypi/simple/${packageName}/`);
   expect(response.status).toEqual(200);
 
   const html = await response.text();
@@ -422,14 +420,12 @@ tap.test('PyPI CLI: should get JSON metadata', async () => {
     return;
   }
 
-  const packageName = 'test-pypi-pkg';
+  const response = await fetch(`${registryUrl}/pypi/pypi/${testPackageName}/json`);
-
-  const response = await fetch(`${registryUrl}/pypi/pypi/${packageName}/json`);
   expect(response.status).toEqual(200);
 
   const metadata = await response.json();
   expect(metadata.info).toBeDefined();
-  expect(metadata.info.name).toEqual(packageName);
+  expect(metadata.info.name).toEqual(testPackageName);
   expect(metadata.releases).toBeDefined();
   expect(metadata.releases['1.0.0']).toBeDefined();
 });
@@ -445,7 +441,7 @@ tap.test('PyPI CLI: should download package with pip', async () => {
 
   // Download (not install) the package
   const result = await runPipCommand(
-    `download test-pypi-pkg==1.0.0 --dest "${downloadDir}" --no-deps`,
+    `download ${testPackageName}==1.0.0 --dest "${downloadDir}" --no-deps`,
     testDir
   );
   console.log('pip download output:', result.stdout);
@@ -457,14 +453,17 @@ tap.test('PyPI CLI: should download package with pip', async () => {
 });
 
 tap.test('PyPI CLI: should search for packages via API', async () => {
-  const packageName = 'test-pypi-pkg';
+  if (!hasTwine) {
+    console.log('Skipping - twine not available (no packages uploaded)');
+    return;
+  }
 
   // Use the JSON API to search/list
-  const response = await fetch(`${registryUrl}/pypi/pypi/${packageName}/json`);
+  const response = await fetch(`${registryUrl}/pypi/pypi/${testPackageName}/json`);
   expect(response.status).toEqual(200);
 
   const metadata = await response.json();
-  expect(metadata.info.name).toEqual(packageName);
+  expect(metadata.info.name).toEqual(testPackageName);
 });
 
 tap.test('PyPI CLI: should fail upload without auth', async () => {
@@ -473,9 +472,9 @@ tap.test('PyPI CLI: should fail upload without auth', async () => {
     return;
   }
 
-  const packageName = 'unauth-pkg';
+  const unauthPkgName = `unauth-pkg-${testRunId}`;
   const version = '1.0.0';
-  const wheelPath = await createTestWheelFile(packageName, version, testDir);
+  const wheelPath = await createTestWheelFile(unauthPkgName, version, testDir);
 
   // Create a pypirc without proper credentials
   const badPypircPath = path.join(testDir, '.bad-pypirc');

ts/00_commitinfo_data.ts

@@ -3,6 +3,6 @@
  */
 export const commitinfo = {
   name: '@push.rocks/smartregistry',
-  version: '2.2.2',
+  version: '2.5.0',
   description: 'A composable TypeScript library implementing OCI, NPM, Maven, Cargo, Composer, PyPI, and RubyGems registries for building unified container and package registries'
 }

ts/cargo/classes.cargoregistry.ts

@@ -3,6 +3,7 @@ import { BaseRegistry } from '../core/classes.baseregistry.js';
 import { RegistryStorage } from '../core/classes.registrystorage.js';
 import { AuthManager } from '../core/classes.authmanager.js';
 import type { IRequestContext, IResponse, IAuthToken } from '../core/interfaces.core.js';
+import type { IProtocolUpstreamConfig } from '../upstream/interfaces.upstream.js';
 import type {
   ICargoIndexEntry,
   ICargoPublishMetadata,
@@ -13,6 +14,7 @@ import type {
   ICargoSearchResponse,
   ICargoSearchResult,
 } from './interfaces.cargo.js';
+import { CargoUpstream } from './classes.cargoupstream.js';
 
 /**
  * Cargo/crates.io registry implementation
@@ -25,12 +27,14 @@ export class CargoRegistry extends BaseRegistry {
   private basePath: string = '/cargo';
   private registryUrl: string;
   private logger: Smartlog;
+  private upstream: CargoUpstream | null = null;
 
   constructor(
     storage: RegistryStorage,
     authManager: AuthManager,
     basePath: string = '/cargo',
-    registryUrl: string = 'http://localhost:5000/cargo'
+    registryUrl: string = 'http://localhost:5000/cargo',
+    upstreamConfig?: IProtocolUpstreamConfig
   ) {
     super();
     this.storage = storage;
@@ -50,6 +54,20 @@ export class CargoRegistry extends BaseRegistry {
       }
     });
     this.logger.enableConsole();
+
+    // Initialize upstream if configured
+    if (upstreamConfig?.enabled) {
+      this.upstream = new CargoUpstream(upstreamConfig, undefined, this.logger);
+    }
+  }
+
+  /**
+   * Clean up resources (timers, connections, etc.)
+   */
+  public destroy(): void {
+    if (this.upstream) {
+      this.upstream.stop();
+    }
   }
 
   public async init(): Promise<void> {
@@ -207,7 +225,25 @@ export class CargoRegistry extends BaseRegistry {
    * Serve index file for a crate
    */
   private async handleIndexFile(crateName: string): Promise<IResponse> {
-    const index = await this.storage.getCargoIndex(crateName);
+    let index = await this.storage.getCargoIndex(crateName);
+
+    // Try upstream if not found locally
+    if ((!index || index.length === 0) && this.upstream) {
+      const upstreamIndex = await this.upstream.fetchCrateIndex(crateName);
+      if (upstreamIndex) {
+        // Parse the newline-delimited JSON
+        const parsedIndex: ICargoIndexEntry[] = upstreamIndex
+          .split('\n')
+          .filter(line => line.trim())
+          .map(line => JSON.parse(line));
+
+        if (parsedIndex.length > 0) {
+          // Cache locally
+          await this.storage.putCargoIndex(crateName, parsedIndex);
+          index = parsedIndex;
+        }
+      }
+    }
 
     if (!index || index.length === 0) {
       return {
@@ -399,7 +435,16 @@ export class CargoRegistry extends BaseRegistry {
   ): Promise<IResponse> {
     this.logger.log('debug', 'handleDownload', { crate: crateName, version });
 
-    const crateFile = await this.storage.getCargoCrate(crateName, version);
+    let crateFile = await this.storage.getCargoCrate(crateName, version);
+
+    // Try upstream if not found locally
+    if (!crateFile && this.upstream) {
+      crateFile = await this.upstream.fetchCrate(crateName, version);
+      if (crateFile) {
+        // Cache locally
+        await this.storage.putCargoCrate(crateName, version, crateFile);
+      }
+    }
 
     if (!crateFile) {
       return {

ts/cargo/classes.cargoupstream.ts

@@ -0,0 +1,159 @@
+import * as plugins from '../plugins.js';
+import { BaseUpstream } from '../upstream/classes.baseupstream.js';
+import type {
+  IProtocolUpstreamConfig,
+  IUpstreamFetchContext,
+  IUpstreamRegistryConfig,
+} from '../upstream/interfaces.upstream.js';
+
+/**
+ * Cargo-specific upstream implementation.
+ *
+ * Handles:
+ * - Crate metadata (index) fetching
+ * - Crate file (.crate) downloading
+ * - Sparse index protocol support
+ * - Content-addressable caching for .crate files
+ */
+export class CargoUpstream extends BaseUpstream {
+  protected readonly protocolName = 'cargo';
+
+  /** Base URL for crate downloads (may differ from index URL) */
+  private readonly downloadUrl: string;
+
+  constructor(
+    config: IProtocolUpstreamConfig,
+    downloadUrl?: string,
+    logger?: plugins.smartlog.Smartlog,
+  ) {
+    super(config, logger);
+    // Default to crates.io download URL if not specified
+    this.downloadUrl = downloadUrl || 'https://static.crates.io/crates';
+  }
+
+  /**
+   * Fetch crate metadata from the sparse index.
+   */
+  public async fetchCrateIndex(crateName: string): Promise<string | null> {
+    const path = this.buildIndexPath(crateName);
+
+    const context: IUpstreamFetchContext = {
+      protocol: 'cargo',
+      resource: crateName,
+      resourceType: 'index',
+      path,
+      method: 'GET',
+      headers: {
+        'accept': 'text/plain',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    if (Buffer.isBuffer(result.body)) {
+      return result.body.toString('utf8');
+    }
+
+    return typeof result.body === 'string' ? result.body : null;
+  }
+
+  /**
+   * Fetch a crate file from upstream.
+   */
+  public async fetchCrate(crateName: string, version: string): Promise<Buffer | null> {
+    // Crate downloads typically go to a different URL than the index
+    const path = `/${crateName}/${crateName}-${version}.crate`;
+
+    const context: IUpstreamFetchContext = {
+      protocol: 'cargo',
+      resource: crateName,
+      resourceType: 'crate',
+      path,
+      method: 'GET',
+      headers: {
+        'accept': 'application/octet-stream',
+      },
+      query: {},
+    };
+
+    // Use special handling for crate downloads
+    const result = await this.fetchCrateFile(crateName, version);
+    return result;
+  }
+
+  /**
+   * Fetch crate file directly from the download URL.
+   */
+  private async fetchCrateFile(crateName: string, version: string): Promise<Buffer | null> {
+    const context: IUpstreamFetchContext = {
+      protocol: 'cargo',
+      resource: crateName,
+      resourceType: 'crate',
+      path: `/${crateName}/${crateName}-${version}.crate`,
+      method: 'GET',
+      headers: {
+        'accept': 'application/octet-stream',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    return Buffer.isBuffer(result.body) ? result.body : Buffer.from(result.body);
+  }
+
+  /**
+   * Build the sparse index path for a crate.
+   *
+   * Path structure:
+   * - 1 char: /1/{name}
+   * - 2 chars: /2/{name}
+   * - 3 chars: /3/{first char}/{name}
+   * - 4+ chars: /{first 2}/{next 2}/{name}
+   */
+  private buildIndexPath(crateName: string): string {
+    const lowerName = crateName.toLowerCase();
+    const len = lowerName.length;
+
+    if (len === 1) {
+      return `/1/${lowerName}`;
+    } else if (len === 2) {
+      return `/2/${lowerName}`;
+    } else if (len === 3) {
+      return `/3/${lowerName[0]}/${lowerName}`;
+    } else {
+      return `/${lowerName.slice(0, 2)}/${lowerName.slice(2, 4)}/${lowerName}`;
+    }
+  }
+
+  /**
+   * Override URL building for Cargo-specific handling.
+   */
+  protected buildUpstreamUrl(
+    upstream: IUpstreamRegistryConfig,
+    context: IUpstreamFetchContext,
+  ): string {
+    let baseUrl = upstream.url;
+
+    // For crate downloads, use the download URL
+    if (context.resourceType === 'crate') {
+      baseUrl = this.downloadUrl;
+    }
+
+    // Remove trailing slash
+    if (baseUrl.endsWith('/')) {
+      baseUrl = baseUrl.slice(0, -1);
+    }
+
+    return `${baseUrl}${context.path}`;
+  }
+}

ts/cargo/index.ts

@@ -3,4 +3,5 @@
  */
 
 export { CargoRegistry } from './classes.cargoregistry.js';
+export { CargoUpstream } from './classes.cargoupstream.js';
 export * from './interfaces.cargo.js';

ts/classes.smartregistry.ts

@@ -11,8 +11,39 @@ import { PypiRegistry } from './pypi/classes.pypiregistry.js';
 import { RubyGemsRegistry } from './rubygems/classes.rubygemsregistry.js';
 
 /**
- * Main registry orchestrator
+ * Main registry orchestrator.
- * Routes requests to appropriate protocol handlers (OCI, NPM, Maven, Cargo, Composer, PyPI, or RubyGems)
+ * Routes requests to appropriate protocol handlers (OCI, NPM, Maven, Cargo, Composer, PyPI, or RubyGems).
+ *
+ * Supports pluggable authentication and storage hooks:
+ *
+ * @example
+ * ```typescript
+ * // Basic usage with default in-memory auth
+ * const registry = new SmartRegistry(config);
+ *
+ * // With custom auth provider (LDAP, OAuth, etc.)
+ * const registry = new SmartRegistry({
+ *   ...config,
+ *   authProvider: new LdapAuthProvider(ldapClient),
+ * });
+ *
+ * // With storage hooks for quota tracking
+ * const registry = new SmartRegistry({
+ *   ...config,
+ *   storageHooks: {
+ *     beforePut: async (ctx) => {
+ *       const quota = await getQuota(ctx.actor?.orgId);
+ *       if (ctx.metadata?.size > quota) {
+ *         return { allowed: false, reason: 'Quota exceeded' };
+ *       }
+ *       return { allowed: true };
+ *     },
+ *     afterPut: async (ctx) => {
+ *       await auditLog('storage.put', ctx);
+ *     }
+ *   }
+ * });
+ * ```
  */
 export class SmartRegistry {
   private storage: RegistryStorage;
@@ -23,8 +54,12 @@ export class SmartRegistry {
 
   constructor(config: IRegistryConfig) {
     this.config = config;
-    this.storage = new RegistryStorage(config.storage);
+
-    this.authManager = new AuthManager(config.auth);
+    // Create storage with optional hooks
+    this.storage = new RegistryStorage(config.storage, config.storageHooks);
+
+    // Create auth manager with optional custom provider
+    this.authManager = new AuthManager(config.auth, config.authProvider);
   }
 
   /**
@@ -46,7 +81,13 @@ export class SmartRegistry {
         realm: this.config.auth.ociTokens.realm,
         service: this.config.auth.ociTokens.service,
       } : undefined;
-      const ociRegistry = new OciRegistry(this.storage, this.authManager, ociBasePath, ociTokens);
+      const ociRegistry = new OciRegistry(
+        this.storage,
+        this.authManager,
+        ociBasePath,
+        ociTokens,
+        this.config.oci.upstream
+      );
       await ociRegistry.init();
       this.registries.set('oci', ociRegistry);
     }
@@ -55,7 +96,13 @@ export class SmartRegistry {
     if (this.config.npm?.enabled) {
       const npmBasePath = this.config.npm.basePath ?? '/npm';
       const registryUrl = `http://localhost:5000${npmBasePath}`; // TODO: Make configurable
-      const npmRegistry = new NpmRegistry(this.storage, this.authManager, npmBasePath, registryUrl);
+      const npmRegistry = new NpmRegistry(
+        this.storage,
+        this.authManager,
+        npmBasePath,
+        registryUrl,
+        this.config.npm.upstream
+      );
       await npmRegistry.init();
       this.registries.set('npm', npmRegistry);
     }
@@ -64,7 +111,13 @@ export class SmartRegistry {
     if (this.config.maven?.enabled) {
       const mavenBasePath = this.config.maven.basePath ?? '/maven';
       const registryUrl = `http://localhost:5000${mavenBasePath}`; // TODO: Make configurable
-      const mavenRegistry = new MavenRegistry(this.storage, this.authManager, mavenBasePath, registryUrl);
+      const mavenRegistry = new MavenRegistry(
+        this.storage,
+        this.authManager,
+        mavenBasePath,
+        registryUrl,
+        this.config.maven.upstream
+      );
       await mavenRegistry.init();
       this.registries.set('maven', mavenRegistry);
     }
@@ -73,7 +126,13 @@ export class SmartRegistry {
     if (this.config.cargo?.enabled) {
       const cargoBasePath = this.config.cargo.basePath ?? '/cargo';
       const registryUrl = `http://localhost:5000${cargoBasePath}`; // TODO: Make configurable
-      const cargoRegistry = new CargoRegistry(this.storage, this.authManager, cargoBasePath, registryUrl);
+      const cargoRegistry = new CargoRegistry(
+        this.storage,
+        this.authManager,
+        cargoBasePath,
+        registryUrl,
+        this.config.cargo.upstream
+      );
       await cargoRegistry.init();
       this.registries.set('cargo', cargoRegistry);
     }
@@ -82,7 +141,13 @@ export class SmartRegistry {
     if (this.config.composer?.enabled) {
       const composerBasePath = this.config.composer.basePath ?? '/composer';
       const registryUrl = `http://localhost:5000${composerBasePath}`; // TODO: Make configurable
-      const composerRegistry = new ComposerRegistry(this.storage, this.authManager, composerBasePath, registryUrl);
+      const composerRegistry = new ComposerRegistry(
+        this.storage,
+        this.authManager,
+        composerBasePath,
+        registryUrl,
+        this.config.composer.upstream
+      );
       await composerRegistry.init();
       this.registries.set('composer', composerRegistry);
     }
@@ -91,7 +156,13 @@ export class SmartRegistry {
     if (this.config.pypi?.enabled) {
       const pypiBasePath = this.config.pypi.basePath ?? '/pypi';
       const registryUrl = `http://localhost:5000`; // TODO: Make configurable
-      const pypiRegistry = new PypiRegistry(this.storage, this.authManager, pypiBasePath, registryUrl);
+      const pypiRegistry = new PypiRegistry(
+        this.storage,
+        this.authManager,
+        pypiBasePath,
+        registryUrl,
+        this.config.pypi.upstream
+      );
       await pypiRegistry.init();
       this.registries.set('pypi', pypiRegistry);
     }
@@ -100,7 +171,13 @@ export class SmartRegistry {
     if (this.config.rubygems?.enabled) {
       const rubygemsBasePath = this.config.rubygems.basePath ?? '/rubygems';
       const registryUrl = `http://localhost:5000${rubygemsBasePath}`; // TODO: Make configurable
-      const rubygemsRegistry = new RubyGemsRegistry(this.storage, this.authManager, rubygemsBasePath, registryUrl);
+      const rubygemsRegistry = new RubyGemsRegistry(
+        this.storage,
+        this.authManager,
+        rubygemsBasePath,
+        registryUrl,
+        this.config.rubygems.upstream
+      );
       await rubygemsRegistry.init();
       this.registries.set('rubygems', rubygemsRegistry);
     }

ts/composer/classes.composerregistry.ts

@@ -7,6 +7,7 @@ import { BaseRegistry } from '../core/classes.baseregistry.js';
 import type { RegistryStorage } from '../core/classes.registrystorage.js';
 import type { AuthManager } from '../core/classes.authmanager.js';
 import type { IRequestContext, IResponse, IAuthToken } from '../core/interfaces.core.js';
+import type { IProtocolUpstreamConfig } from '../upstream/interfaces.upstream.js';
 import { isBinaryData, toBuffer } from '../core/helpers.buffer.js';
 import type {
   IComposerPackage,
@@ -22,24 +23,41 @@ import {
   generatePackagesJson,
   sortVersions,
 } from './helpers.composer.js';
+import { ComposerUpstream } from './classes.composerupstream.js';
 
 export class ComposerRegistry extends BaseRegistry {
   private storage: RegistryStorage;
   private authManager: AuthManager;
   private basePath: string = '/composer';
   private registryUrl: string;
+  private upstream: ComposerUpstream | null = null;
 
   constructor(
     storage: RegistryStorage,
     authManager: AuthManager,
     basePath: string = '/composer',
-    registryUrl: string = 'http://localhost:5000/composer'
+    registryUrl: string = 'http://localhost:5000/composer',
+    upstreamConfig?: IProtocolUpstreamConfig
   ) {
     super();
     this.storage = storage;
     this.authManager = authManager;
     this.basePath = basePath;
     this.registryUrl = registryUrl;
+
+    // Initialize upstream if configured
+    if (upstreamConfig?.enabled) {
+      this.upstream = new ComposerUpstream(upstreamConfig);
+    }
+  }
+
+  /**
+   * Clean up resources (timers, connections, etc.)
+   */
+  public destroy(): void {
+    if (this.upstream) {
+      this.upstream.stop();
+    }
   }
 
   public async init(): Promise<void> {
@@ -161,7 +179,26 @@ export class ComposerRegistry extends BaseRegistry {
     token: IAuthToken | null
   ): Promise<IResponse> {
     // Read operations are public, no authentication required
-    const metadata = await this.storage.getComposerPackageMetadata(vendorPackage);
+    let metadata = await this.storage.getComposerPackageMetadata(vendorPackage);
+
+    // Try upstream if not found locally
+    if (!metadata && this.upstream) {
+      const [vendor, packageName] = vendorPackage.split('/');
+      if (vendor && packageName) {
+        const upstreamMetadata = includeDev
+          ? await this.upstream.fetchPackageDevMetadata(vendor, packageName)
+          : await this.upstream.fetchPackageMetadata(vendor, packageName);
+
+        if (upstreamMetadata && upstreamMetadata.packages) {
+          // Store upstream metadata locally
+          metadata = {
+            packages: upstreamMetadata.packages,
+            lastModified: new Date().toUTCString(),
+          };
+          await this.storage.putComposerPackageMetadata(vendorPackage, metadata);
+        }
+      }
+    }
 
     if (!metadata) {
       return {

ts/composer/classes.composerupstream.ts

@@ -0,0 +1,200 @@
+import * as plugins from '../plugins.js';
+import { BaseUpstream } from '../upstream/classes.baseupstream.js';
+import type {
+  IProtocolUpstreamConfig,
+  IUpstreamFetchContext,
+  IUpstreamRegistryConfig,
+} from '../upstream/interfaces.upstream.js';
+
+/**
+ * Composer-specific upstream implementation.
+ *
+ * Handles:
+ * - Package metadata fetching (packages.json, provider-includes)
+ * - Package version metadata (p2/{vendor}/{package}.json)
+ * - Dist file (zip) proxying
+ * - Packagist v2 API support
+ */
+export class ComposerUpstream extends BaseUpstream {
+  protected readonly protocolName = 'composer';
+
+  constructor(
+    config: IProtocolUpstreamConfig,
+    logger?: plugins.smartlog.Smartlog,
+  ) {
+    super(config, logger);
+  }
+
+  /**
+   * Fetch the root packages.json from upstream.
+   */
+  public async fetchPackagesJson(): Promise<any | null> {
+    const context: IUpstreamFetchContext = {
+      protocol: 'composer',
+      resource: '*',
+      resourceType: 'root',
+      path: '/packages.json',
+      method: 'GET',
+      headers: {
+        'accept': 'application/json',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    if (Buffer.isBuffer(result.body)) {
+      return JSON.parse(result.body.toString('utf8'));
+    }
+
+    return result.body;
+  }
+
+  /**
+   * Fetch package metadata using v2 API (p2/{vendor}/{package}.json).
+   */
+  public async fetchPackageMetadata(vendor: string, packageName: string): Promise<any | null> {
+    const fullName = `${vendor}/${packageName}`;
+    const path = `/p2/${vendor}/${packageName}.json`;
+
+    const context: IUpstreamFetchContext = {
+      protocol: 'composer',
+      resource: fullName,
+      resourceType: 'metadata',
+      path,
+      method: 'GET',
+      headers: {
+        'accept': 'application/json',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    if (Buffer.isBuffer(result.body)) {
+      return JSON.parse(result.body.toString('utf8'));
+    }
+
+    return result.body;
+  }
+
+  /**
+   * Fetch package metadata with dev versions (p2/{vendor}/{package}~dev.json).
+   */
+  public async fetchPackageDevMetadata(vendor: string, packageName: string): Promise<any | null> {
+    const fullName = `${vendor}/${packageName}`;
+    const path = `/p2/${vendor}/${packageName}~dev.json`;
+
+    const context: IUpstreamFetchContext = {
+      protocol: 'composer',
+      resource: fullName,
+      resourceType: 'metadata-dev',
+      path,
+      method: 'GET',
+      headers: {
+        'accept': 'application/json',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    if (Buffer.isBuffer(result.body)) {
+      return JSON.parse(result.body.toString('utf8'));
+    }
+
+    return result.body;
+  }
+
+  /**
+   * Fetch a provider-includes file.
+   */
+  public async fetchProviderIncludes(path: string): Promise<any | null> {
+    const context: IUpstreamFetchContext = {
+      protocol: 'composer',
+      resource: '*',
+      resourceType: 'provider',
+      path: path.startsWith('/') ? path : `/${path}`,
+      method: 'GET',
+      headers: {
+        'accept': 'application/json',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    if (Buffer.isBuffer(result.body)) {
+      return JSON.parse(result.body.toString('utf8'));
+    }
+
+    return result.body;
+  }
+
+  /**
+   * Fetch a dist file (zip) from upstream.
+   */
+  public async fetchDist(url: string): Promise<Buffer | null> {
+    // Parse the URL to get the path
+    let path: string;
+    try {
+      const parsed = new URL(url);
+      path = parsed.pathname;
+    } catch {
+      path = url;
+    }
+
+    const context: IUpstreamFetchContext = {
+      protocol: 'composer',
+      resource: '*',
+      resourceType: 'dist',
+      path,
+      method: 'GET',
+      headers: {
+        'accept': 'application/zip, application/octet-stream',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    return Buffer.isBuffer(result.body) ? result.body : Buffer.from(result.body);
+  }
+
+  /**
+   * Override URL building for Composer-specific handling.
+   */
+  protected buildUpstreamUrl(
+    upstream: IUpstreamRegistryConfig,
+    context: IUpstreamFetchContext,
+  ): string {
+    let baseUrl = upstream.url;
+
+    // Remove trailing slash
+    if (baseUrl.endsWith('/')) {
+      baseUrl = baseUrl.slice(0, -1);
+    }
+
+    return `${baseUrl}${context.path}`;
+  }
+}

ts/composer/index.ts

@@ -4,5 +4,6 @@
  */
 
 export { ComposerRegistry } from './classes.composerregistry.js';
+export { ComposerUpstream } from './classes.composerupstream.js';
 export * from './interfaces.composer.js';
 export * from './helpers.composer.js';

ts/core/classes.authmanager.ts

@@ -1,109 +1,79 @@
 import type { IAuthConfig, IAuthToken, ICredentials, TRegistryProtocol } from './interfaces.core.js';
-import * as crypto from 'crypto';
+import type { IAuthProvider, ITokenOptions } from './interfaces.auth.js';
+import { DefaultAuthProvider } from './classes.defaultauthprovider.js';
 
 /**
- * Unified authentication manager for all registry protocols
+ * Unified authentication manager for all registry protocols.
- * Handles both NPM UUID tokens and OCI JWT tokens
+ * Delegates to a pluggable IAuthProvider for actual auth operations.
+ *
+ * @example
+ * ```typescript
+ * // Use default in-memory provider
+ * const auth = new AuthManager(config);
+ *
+ * // Use custom provider (LDAP, OAuth, etc.)
+ * const auth = new AuthManager(config, new LdapAuthProvider(ldapClient));
+ * ```
  */
 export class AuthManager {
-  private tokenStore: Map<string, IAuthToken> = new Map();
+  private provider: IAuthProvider;
-  private userCredentials: Map<string, string> = new Map(); // username -> password hash (mock)
 
-  constructor(private config: IAuthConfig) {}
+  constructor(
+    private config: IAuthConfig,
+    provider?: IAuthProvider
+  ) {
+    // Use provided provider or default in-memory implementation
+    this.provider = provider || new DefaultAuthProvider(config);
+  }
 
   /**
    * Initialize the auth manager
    */
   public async init(): Promise<void> {
-    // Initialize token store (in-memory for now)
+    if (this.provider.init) {
-    // In production, this could be Redis or a database
+      await this.provider.init();
+    }
   }
 
   // ========================================================================
-  // UUID TOKEN CREATION (Base method for NPM, Maven, etc.)
+  // UNIFIED AUTHENTICATION (Delegated to Provider)
   // ========================================================================
 
   /**
-   * Create a UUID-based token with custom scopes (base method)
+   * Authenticate user credentials
-   * @param userId - User ID
+   * @param credentials - Username and password
-   * @param protocol - Protocol type
+   * @returns User ID or null
-   * @param scopes - Permission scopes
-   * @param readonly - Whether the token is readonly
-   * @returns UUID token string
    */
-  private async createUuidToken(
+  public async authenticate(credentials: ICredentials): Promise<string | null> {
-    userId: string,
+    return this.provider.authenticate(credentials);
-    protocol: TRegistryProtocol,
-    scopes: string[],
-    readonly: boolean = false
-  ): Promise<string> {
-    const token = this.generateUuid();
-    const authToken: IAuthToken = {
-      type: protocol,
-      userId,
-      scopes,
-      readonly,
-      metadata: {
-        created: new Date().toISOString(),
-      },
-    };
-
-    this.tokenStore.set(token, authToken);
-    return token;
   }
 
   /**
-   * Generic protocol token creation (internal helper)
+   * Validate any token (NPM, Maven, OCI, PyPI, RubyGems, Composer, Cargo)
-   * @param userId - User ID
+   * @param tokenString - Token string (UUID or JWT)
-   * @param protocol - Protocol type (npm, maven, composer, etc.)
+   * @param protocol - Expected protocol type (optional, improves performance)
-   * @param readonly - Whether the token is readonly
-   * @returns UUID token string
-   */
-  private async createProtocolToken(
-    userId: string,
-    protocol: TRegistryProtocol,
-    readonly: boolean
-  ): Promise<string> {
-    const scopes = readonly
-      ? [`${protocol}:*:*:read`]
-      : [`${protocol}:*:*:*`];
-    return this.createUuidToken(userId, protocol, scopes, readonly);
-  }
-
-  /**
-   * Generic protocol token validation (internal helper)
-   * @param token - UUID token string
-   * @param protocol - Expected protocol type
    * @returns Auth token object or null
    */
-  private async validateProtocolToken(
+  public async validateToken(
-    token: string,
+    tokenString: string,
-    protocol: TRegistryProtocol
+    protocol?: TRegistryProtocol
   ): Promise<IAuthToken | null> {
-    if (!this.isValidUuid(token)) {
+    return this.provider.validateToken(tokenString, protocol);
-      return null;
-    }
-
-    const authToken = this.tokenStore.get(token);
-    if (!authToken || authToken.type !== protocol) {
-      return null;
-    }
-
-    // Check expiration if set
-    if (authToken.expiresAt && authToken.expiresAt < new Date()) {
-      this.tokenStore.delete(token);
-      return null;
-    }
-
-    return authToken;
   }
 
   /**
-   * Generic protocol token revocation (internal helper)
+   * Check if token has permission for an action
-   * @param token - UUID token string
+   * @param token - Auth token (or null for anonymous)
+   * @param resource - Resource being accessed (e.g., "npm:package:foo")
+   * @param action - Action being performed (read, write, push, pull, delete)
+   * @returns true if authorized
    */
-  private async revokeProtocolToken(token: string): Promise<void> {
+  public async authorize(
-    this.tokenStore.delete(token);
+    token: IAuthToken | null,
+    resource: string,
+    action: string
+  ): Promise<boolean> {
+    return this.provider.authorize(token, resource, action);
   }
 
   // ========================================================================
@@ -120,7 +90,7 @@ export class AuthManager {
     if (!this.config.npmTokens.enabled) {
       throw new Error('NPM tokens are not enabled');
     }
-    return this.createProtocolToken(userId, 'npm', readonly);
+    return this.provider.createToken(userId, 'npm', { readonly });
   }
 
   /**
@@ -129,7 +99,7 @@ export class AuthManager {
    * @returns Auth token object or null
    */
   public async validateNpmToken(token: string): Promise<IAuthToken | null> {
-    return this.validateProtocolToken(token, 'npm');
+    return this.provider.validateToken(token, 'npm');
   }
 
   /**
@@ -137,7 +107,7 @@ export class AuthManager {
    * @param token - NPM UUID token
    */
   public async revokeNpmToken(token: string): Promise<void> {
-    return this.revokeProtocolToken(token);
+    return this.provider.revokeToken(token);
   }
 
   /**
@@ -149,20 +119,12 @@ export class AuthManager {
     key: string;
     readonly: boolean;
     created: string;
+    protocol?: TRegistryProtocol;
   }>> {
-    const tokens: Array<{key: string; readonly: boolean; created: string}> = [];
+    if (this.provider.listUserTokens) {
-
+      return this.provider.listUserTokens(userId);
-    for (const [token, authToken] of this.tokenStore.entries()) {
-      if (authToken.userId === userId) {
-        tokens.push({
-          key: this.hashToken(token),
-          readonly: authToken.readonly || false,
-          created: authToken.metadata?.created || 'unknown',
-        });
     }
-    }
+    return [];
-
-    return tokens;
   }
 
   // ========================================================================
@@ -174,39 +136,17 @@ export class AuthManager {
    * @param userId - User ID
    * @param scopes - Permission scopes
    * @param expiresIn - Expiration time in seconds
-   * @returns JWT token string (HMAC-SHA256 signed)
+   * @returns JWT token string
    */
   public async createOciToken(
     userId: string,
     scopes: string[],
     expiresIn: number = 3600
   ): Promise<string> {
-    if (!this.config.ociTokens.enabled) {
+    if (!this.config.ociTokens?.enabled) {
       throw new Error('OCI tokens are not enabled');
     }
-
+    return this.provider.createToken(userId, 'oci', { scopes, expiresIn });
-    const now = Math.floor(Date.now() / 1000);
-    const payload = {
-      iss: this.config.ociTokens.realm,
-      sub: userId,
-      aud: this.config.ociTokens.service,
-      exp: now + expiresIn,
-      nbf: now,
-      iat: now,
-      access: this.scopesToOciAccess(scopes),
-    };
-
-    // Create JWT with HMAC-SHA256 signature
-    const header = { alg: 'HS256', typ: 'JWT' };
-    const headerB64 = Buffer.from(JSON.stringify(header)).toString('base64url');
-    const payloadB64 = Buffer.from(JSON.stringify(payload)).toString('base64url');
-
-    const signature = crypto
-      .createHmac('sha256', this.config.jwtSecret)
-      .update(`${headerB64}.${payloadB64}`)
-      .digest('base64url');
-
-    return `${headerB64}.${payloadB64}.${signature}`;
   }
 
   /**
@@ -215,80 +155,7 @@ export class AuthManager {
    * @returns Auth token object or null
    */
   public async validateOciToken(jwt: string): Promise<IAuthToken | null> {
-    try {
+    return this.provider.validateToken(jwt, 'oci');
-      const parts = jwt.split('.');
-      if (parts.length !== 3) {
-        return null;
-      }
-
-      const [headerB64, payloadB64, signatureB64] = parts;
-
-      // Verify signature
-      const expectedSignature = crypto
-        .createHmac('sha256', this.config.jwtSecret)
-        .update(`${headerB64}.${payloadB64}`)
-        .digest('base64url');
-
-      if (signatureB64 !== expectedSignature) {
-        return null;
-      }
-
-      // Decode and parse payload
-      const payload = JSON.parse(Buffer.from(payloadB64, 'base64url').toString('utf-8'));
-
-      // Check expiration
-      const now = Math.floor(Date.now() / 1000);
-      if (payload.exp && payload.exp < now) {
-        return null;
-      }
-
-      // Check not-before time
-      if (payload.nbf && payload.nbf > now) {
-        return null;
-      }
-
-      // Convert to unified token format
-      const scopes = this.ociAccessToScopes(payload.access || []);
-
-      return {
-        type: 'oci',
-        userId: payload.sub,
-        scopes,
-        expiresAt: payload.exp ? new Date(payload.exp * 1000) : undefined,
-        metadata: {
-          iss: payload.iss,
-          aud: payload.aud,
-        },
-      };
-    } catch (error) {
-      return null;
-    }
-  }
-
-  // ========================================================================
-  // UNIFIED AUTHENTICATION
-  // ========================================================================
-
-  /**
-   * Authenticate user credentials
-   * @param credentials - Username and password
-   * @returns User ID or null
-   */
-  public async authenticate(credentials: ICredentials): Promise<string | null> {
-    // Mock authentication - in production, verify against database
-    const storedPassword = this.userCredentials.get(credentials.username);
-
-    if (!storedPassword) {
-      // Auto-register for testing (remove in production)
-      this.userCredentials.set(credentials.username, credentials.password);
-      return credentials.username;
-    }
-
-    if (storedPassword === credentials.password) {
-      return credentials.username;
-    }
-
-    return null;
   }
 
   // ========================================================================
@@ -302,7 +169,7 @@ export class AuthManager {
    * @returns Maven UUID token
    */
   public async createMavenToken(userId: string, readonly: boolean = false): Promise<string> {
-    return this.createProtocolToken(userId, 'maven', readonly);
+    return this.provider.createToken(userId, 'maven', { readonly });
   }
 
   /**
@@ -311,7 +178,7 @@ export class AuthManager {
    * @returns Auth token object or null
    */
   public async validateMavenToken(token: string): Promise<IAuthToken | null> {
-    return this.validateProtocolToken(token, 'maven');
+    return this.provider.validateToken(token, 'maven');
   }
 
   /**
@@ -319,7 +186,7 @@ export class AuthManager {
    * @param token - Maven UUID token
    */
   public async revokeMavenToken(token: string): Promise<void> {
-    return this.revokeProtocolToken(token);
+    return this.provider.revokeToken(token);
   }
 
   // ========================================================================
@@ -333,7 +200,7 @@ export class AuthManager {
    * @returns Composer UUID token
    */
   public async createComposerToken(userId: string, readonly: boolean = false): Promise<string> {
-    return this.createProtocolToken(userId, 'composer', readonly);
+    return this.provider.createToken(userId, 'composer', { readonly });
   }
 
   /**
@@ -342,7 +209,7 @@ export class AuthManager {
    * @returns Auth token object or null
    */
   public async validateComposerToken(token: string): Promise<IAuthToken | null> {
-    return this.validateProtocolToken(token, 'composer');
+    return this.provider.validateToken(token, 'composer');
   }
 
   /**
@@ -350,7 +217,7 @@ export class AuthManager {
    * @param token - Composer UUID token
    */
   public async revokeComposerToken(token: string): Promise<void> {
-    return this.revokeProtocolToken(token);
+    return this.provider.revokeToken(token);
   }
 
   // ========================================================================
@@ -364,7 +231,7 @@ export class AuthManager {
    * @returns Cargo UUID token
    */
   public async createCargoToken(userId: string, readonly: boolean = false): Promise<string> {
-    return this.createProtocolToken(userId, 'cargo', readonly);
+    return this.provider.createToken(userId, 'cargo', { readonly });
   }
 
   /**
@@ -373,7 +240,7 @@ export class AuthManager {
    * @returns Auth token object or null
    */
   public async validateCargoToken(token: string): Promise<IAuthToken | null> {
-    return this.validateProtocolToken(token, 'cargo');
+    return this.provider.validateToken(token, 'cargo');
   }
 
   /**
@@ -381,7 +248,7 @@ export class AuthManager {
    * @param token - Cargo UUID token
    */
   public async revokeCargoToken(token: string): Promise<void> {
-    return this.revokeProtocolToken(token);
+    return this.provider.revokeToken(token);
   }
 
   // ========================================================================
@@ -395,7 +262,7 @@ export class AuthManager {
    * @returns PyPI UUID token
    */
   public async createPypiToken(userId: string, readonly: boolean = false): Promise<string> {
-    return this.createProtocolToken(userId, 'pypi', readonly);
+    return this.provider.createToken(userId, 'pypi', { readonly });
   }
 
   /**
@@ -404,7 +271,7 @@ export class AuthManager {
    * @returns Auth token object or null
    */
   public async validatePypiToken(token: string): Promise<IAuthToken | null> {
-    return this.validateProtocolToken(token, 'pypi');
+    return this.provider.validateToken(token, 'pypi');
   }
 
   /**
@@ -412,7 +279,7 @@ export class AuthManager {
    * @param token - PyPI UUID token
    */
   public async revokePypiToken(token: string): Promise<void> {
-    return this.revokeProtocolToken(token);
+    return this.provider.revokeToken(token);
   }
 
   // ========================================================================
@@ -426,7 +293,7 @@ export class AuthManager {
    * @returns RubyGems UUID token
    */
   public async createRubyGemsToken(userId: string, readonly: boolean = false): Promise<string> {
-    return this.createProtocolToken(userId, 'rubygems', readonly);
+    return this.provider.createToken(userId, 'rubygems', { readonly });
   }
 
   /**
@@ -435,7 +302,7 @@ export class AuthManager {
    * @returns Auth token object or null
    */
   public async validateRubyGemsToken(token: string): Promise<IAuthToken | null> {
-    return this.validateProtocolToken(token, 'rubygems');
+    return this.provider.validateToken(token, 'rubygems');
   }
 
   /**
@@ -443,211 +310,6 @@ export class AuthManager {
    * @param token - RubyGems UUID token
    */
   public async revokeRubyGemsToken(token: string): Promise<void> {
-    return this.revokeProtocolToken(token);
+    return this.provider.revokeToken(token);
-  }
-
-  // ========================================================================
-  // UNIFIED AUTHENTICATION
-  // ========================================================================
-
-  /**
-   * Validate any token (NPM, Maven, OCI, PyPI, RubyGems, Composer, Cargo)
-   * Optimized: O(1) lookup when protocol hint provided
-   * @param tokenString - Token string (UUID or JWT)
-   * @param protocol - Expected protocol type (optional, improves performance)
-   * @returns Auth token object or null
-   */
-  public async validateToken(
-    tokenString: string,
-    protocol?: TRegistryProtocol
-  ): Promise<IAuthToken | null> {
-    // OCI uses JWT (contains dots), not UUID - check first if OCI is expected
-    if (protocol === 'oci' || tokenString.includes('.')) {
-      const ociToken = await this.validateOciToken(tokenString);
-      if (ociToken && (!protocol || protocol === 'oci')) {
-        return ociToken;
-      }
-      // If protocol was explicitly OCI but validation failed, return null
-      if (protocol === 'oci') {
-        return null;
-      }
-    }
-
-    // UUID-based tokens: single O(1) Map lookup
-    if (this.isValidUuid(tokenString)) {
-      const authToken = this.tokenStore.get(tokenString);
-      if (authToken) {
-        // If protocol specified, verify it matches
-        if (protocol && authToken.type !== protocol) {
-          return null;
-        }
-        // Check expiration
-        if (authToken.expiresAt && authToken.expiresAt < new Date()) {
-          this.tokenStore.delete(tokenString);
-          return null;
-        }
-        return authToken;
-      }
-    }
-
-    return null;
-  }
-
-  /**
-   * Check if token has permission for an action
-   * @param token - Auth token
-   * @param resource - Resource being accessed (e.g., "package:foo" or "repository:bar")
-   * @param action - Action being performed (read, write, push, pull, delete)
-   * @returns true if authorized
-   */
-  public async authorize(
-    token: IAuthToken | null,
-    resource: string,
-    action: string
-  ): Promise<boolean> {
-    if (!token) {
-      return false;
-    }
-
-    // Check readonly flag
-    if (token.readonly && ['write', 'push', 'delete'].includes(action)) {
-      return false;
-    }
-
-    // Check scopes
-    for (const scope of token.scopes) {
-      if (this.matchesScope(scope, resource, action)) {
-        return true;
-      }
-    }
-
-    return false;
-  }
-
-  // ========================================================================
-  // HELPER METHODS
-  // ========================================================================
-
-  /**
-   * Check if a scope matches a resource and action
-   * Scope format: "{protocol}:{type}:{name}:{action}"
-   * Examples:
-   * - "npm:*:*" - All NPM access
-   * - "npm:package:foo:*" - All actions on package foo
-   * - "npm:package:foo:read" - Read-only on package foo
-   * - "oci:repository:*:pull" - Pull from any OCI repo
-   */
-  private matchesScope(scope: string, resource: string, action: string): boolean {
-    const scopeParts = scope.split(':');
-    const resourceParts = resource.split(':');
-
-    // Scope must have at least protocol:type:name:action
-    if (scopeParts.length < 4) {
-      return false;
-    }
-
-    const [scopeProtocol, scopeType, scopeName, scopeAction] = scopeParts;
-    const [resourceProtocol, resourceType, resourceName] = resourceParts;
-
-    // Check protocol
-    if (scopeProtocol !== '*' && scopeProtocol !== resourceProtocol) {
-      return false;
-    }
-
-    // Check type
-    if (scopeType !== '*' && scopeType !== resourceType) {
-      return false;
-    }
-
-    // Check name
-    if (scopeName !== '*' && scopeName !== resourceName) {
-      return false;
-    }
-
-    // Check action
-    if (scopeAction !== '*' && scopeAction !== action) {
-      // Map action aliases
-      const actionAliases: Record<string, string[]> = {
-        read: ['pull', 'get'],
-        write: ['push', 'put', 'post'],
-      };
-
-      const aliases = actionAliases[scopeAction] || [];
-      if (!aliases.includes(action)) {
-        return false;
-      }
-    }
-
-    return true;
-  }
-
-  /**
-   * Convert unified scopes to OCI access array
-   */
-  private scopesToOciAccess(scopes: string[]): Array<{
-    type: string;
-    name: string;
-    actions: string[];
-  }> {
-    const access: Array<{type: string; name: string; actions: string[]}> = [];
-
-    for (const scope of scopes) {
-      const parts = scope.split(':');
-      if (parts.length >= 4 && parts[0] === 'oci') {
-        access.push({
-          type: parts[1],
-          name: parts[2],
-          actions: [parts[3]],
-        });
-      }
-    }
-
-    return access;
-  }
-
-  /**
-   * Convert OCI access array to unified scopes
-   */
-  private ociAccessToScopes(access: Array<{
-    type: string;
-    name: string;
-    actions: string[];
-  }>): string[] {
-    const scopes: string[] = [];
-
-    for (const item of access) {
-      for (const action of item.actions) {
-        scopes.push(`oci:${item.type}:${item.name}:${action}`);
-      }
-    }
-
-    return scopes;
-  }
-
-  /**
-   * Generate UUID for NPM tokens
-   */
-  private generateUuid(): string {
-    return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, (c) => {
-      const r = (Math.random() * 16) | 0;
-      const v = c === 'x' ? r : (r & 0x3) | 0x8;
-      return v.toString(16);
-    });
-  }
-
-  /**
-   * Check if string is a valid UUID
-   */
-  private isValidUuid(str: string): boolean {
-    const uuidRegex = /^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i;
-    return uuidRegex.test(str);
-  }
-
-  /**
-   * Hash a token for identification (SHA-512 mock)
-   */
-  private hashToken(token: string): string {
-    // In production, use actual SHA-512
-    return `sha512-${token.substring(0, 16)}...`;
   }
 }

ts/core/classes.defaultauthprovider.ts

@@ -0,0 +1,393 @@
+import * as crypto from 'crypto';
+import type { IAuthProvider, ITokenOptions } from './interfaces.auth.js';
+import type { IAuthConfig, IAuthToken, ICredentials, TRegistryProtocol } from './interfaces.core.js';
+
+/**
+ * Default in-memory authentication provider.
+ * This is the reference implementation that stores tokens in memory.
+ * For production use, implement IAuthProvider with Redis, database, or external auth.
+ */
+export class DefaultAuthProvider implements IAuthProvider {
+  private tokenStore: Map<string, IAuthToken> = new Map();
+  private userCredentials: Map<string, string> = new Map(); // username -> password hash (mock)
+
+  constructor(private config: IAuthConfig) {}
+
+  /**
+   * Initialize the auth provider
+   */
+  public async init(): Promise<void> {
+    // Initialize token store (in-memory for now)
+    // In production, this could be Redis or a database
+  }
+
+  // ========================================================================
+  // IAuthProvider Implementation
+  // ========================================================================
+
+  /**
+   * Authenticate user credentials
+   */
+  public async authenticate(credentials: ICredentials): Promise<string | null> {
+    // Mock authentication - in production, verify against database/LDAP
+    const storedPassword = this.userCredentials.get(credentials.username);
+
+    if (!storedPassword) {
+      // Auto-register for testing (remove in production)
+      this.userCredentials.set(credentials.username, credentials.password);
+      return credentials.username;
+    }
+
+    if (storedPassword === credentials.password) {
+      return credentials.username;
+    }
+
+    return null;
+  }
+
+  /**
+   * Validate any token (NPM, Maven, OCI, PyPI, RubyGems, Composer, Cargo)
+   */
+  public async validateToken(
+    tokenString: string,
+    protocol?: TRegistryProtocol
+  ): Promise<IAuthToken | null> {
+    // OCI uses JWT (contains dots), not UUID - check first if OCI is expected
+    if (protocol === 'oci' || tokenString.includes('.')) {
+      const ociToken = await this.validateOciToken(tokenString);
+      if (ociToken && (!protocol || protocol === 'oci')) {
+        return ociToken;
+      }
+      // If protocol was explicitly OCI but validation failed, return null
+      if (protocol === 'oci') {
+        return null;
+      }
+    }
+
+    // UUID-based tokens: single O(1) Map lookup
+    if (this.isValidUuid(tokenString)) {
+      const authToken = this.tokenStore.get(tokenString);
+      if (authToken) {
+        // If protocol specified, verify it matches
+        if (protocol && authToken.type !== protocol) {
+          return null;
+        }
+        // Check expiration
+        if (authToken.expiresAt && authToken.expiresAt < new Date()) {
+          this.tokenStore.delete(tokenString);
+          return null;
+        }
+        return authToken;
+      }
+    }
+
+    return null;
+  }
+
+  /**
+   * Create a new token for a user
+   */
+  public async createToken(
+    userId: string,
+    protocol: TRegistryProtocol,
+    options?: ITokenOptions
+  ): Promise<string> {
+    // OCI tokens use JWT
+    if (protocol === 'oci') {
+      return this.createOciToken(userId, options?.scopes || ['oci:*:*:*'], options?.expiresIn || 3600);
+    }
+
+    // All other protocols use UUID tokens
+    const token = this.generateUuid();
+    const scopes = options?.scopes || (options?.readonly
+      ? [`${protocol}:*:*:read`]
+      : [`${protocol}:*:*:*`]);
+
+    const authToken: IAuthToken = {
+      type: protocol,
+      userId,
+      scopes,
+      readonly: options?.readonly,
+      expiresAt: options?.expiresIn ? new Date(Date.now() + options.expiresIn * 1000) : undefined,
+      metadata: {
+        created: new Date().toISOString(),
+      },
+    };
+
+    this.tokenStore.set(token, authToken);
+    return token;
+  }
+
+  /**
+   * Revoke a token
+   */
+  public async revokeToken(token: string): Promise<void> {
+    this.tokenStore.delete(token);
+  }
+
+  /**
+   * Check if token has permission for an action
+   */
+  public async authorize(
+    token: IAuthToken | null,
+    resource: string,
+    action: string
+  ): Promise<boolean> {
+    if (!token) {
+      return false;
+    }
+
+    // Check readonly flag
+    if (token.readonly && ['write', 'push', 'delete'].includes(action)) {
+      return false;
+    }
+
+    // Check scopes
+    for (const scope of token.scopes) {
+      if (this.matchesScope(scope, resource, action)) {
+        return true;
+      }
+    }
+
+    return false;
+  }
+
+  /**
+   * List all tokens for a user
+   */
+  public async listUserTokens(userId: string): Promise<Array<{
+    key: string;
+    readonly: boolean;
+    created: string;
+    protocol?: TRegistryProtocol;
+  }>> {
+    const tokens: Array<{key: string; readonly: boolean; created: string; protocol?: TRegistryProtocol}> = [];
+
+    for (const [token, authToken] of this.tokenStore.entries()) {
+      if (authToken.userId === userId) {
+        tokens.push({
+          key: this.hashToken(token),
+          readonly: authToken.readonly || false,
+          created: authToken.metadata?.created || 'unknown',
+          protocol: authToken.type,
+        });
+      }
+    }
+
+    return tokens;
+  }
+
+  // ========================================================================
+  // OCI JWT Token Methods
+  // ========================================================================
+
+  /**
+   * Create an OCI JWT token
+   */
+  private async createOciToken(
+    userId: string,
+    scopes: string[],
+    expiresIn: number = 3600
+  ): Promise<string> {
+    if (!this.config.ociTokens?.enabled) {
+      throw new Error('OCI tokens are not enabled');
+    }
+
+    const now = Math.floor(Date.now() / 1000);
+    const payload = {
+      iss: this.config.ociTokens.realm,
+      sub: userId,
+      aud: this.config.ociTokens.service,
+      exp: now + expiresIn,
+      nbf: now,
+      iat: now,
+      access: this.scopesToOciAccess(scopes),
+    };
+
+    // Create JWT with HMAC-SHA256 signature
+    const header = { alg: 'HS256', typ: 'JWT' };
+    const headerB64 = Buffer.from(JSON.stringify(header)).toString('base64url');
+    const payloadB64 = Buffer.from(JSON.stringify(payload)).toString('base64url');
+
+    const signature = crypto
+      .createHmac('sha256', this.config.jwtSecret)
+      .update(`${headerB64}.${payloadB64}`)
+      .digest('base64url');
+
+    return `${headerB64}.${payloadB64}.${signature}`;
+  }
+
+  /**
+   * Validate an OCI JWT token
+   */
+  private async validateOciToken(jwt: string): Promise<IAuthToken | null> {
+    try {
+      const parts = jwt.split('.');
+      if (parts.length !== 3) {
+        return null;
+      }
+
+      const [headerB64, payloadB64, signatureB64] = parts;
+
+      // Verify signature
+      const expectedSignature = crypto
+        .createHmac('sha256', this.config.jwtSecret)
+        .update(`${headerB64}.${payloadB64}`)
+        .digest('base64url');
+
+      if (signatureB64 !== expectedSignature) {
+        return null;
+      }
+
+      // Decode and parse payload
+      const payload = JSON.parse(Buffer.from(payloadB64, 'base64url').toString('utf-8'));
+
+      // Check expiration
+      const now = Math.floor(Date.now() / 1000);
+      if (payload.exp && payload.exp < now) {
+        return null;
+      }
+
+      // Check not-before time
+      if (payload.nbf && payload.nbf > now) {
+        return null;
+      }
+
+      // Convert to unified token format
+      const scopes = this.ociAccessToScopes(payload.access || []);
+
+      return {
+        type: 'oci',
+        userId: payload.sub,
+        scopes,
+        expiresAt: payload.exp ? new Date(payload.exp * 1000) : undefined,
+        metadata: {
+          iss: payload.iss,
+          aud: payload.aud,
+        },
+      };
+    } catch (error) {
+      return null;
+    }
+  }
+
+  // ========================================================================
+  // Helper Methods
+  // ========================================================================
+
+  /**
+   * Check if a scope matches a resource and action
+   */
+  private matchesScope(scope: string, resource: string, action: string): boolean {
+    const scopeParts = scope.split(':');
+    const resourceParts = resource.split(':');
+
+    // Scope must have at least protocol:type:name:action
+    if (scopeParts.length < 4) {
+      return false;
+    }
+
+    const [scopeProtocol, scopeType, scopeName, scopeAction] = scopeParts;
+    const [resourceProtocol, resourceType, resourceName] = resourceParts;
+
+    // Check protocol
+    if (scopeProtocol !== '*' && scopeProtocol !== resourceProtocol) {
+      return false;
+    }
+
+    // Check type
+    if (scopeType !== '*' && scopeType !== resourceType) {
+      return false;
+    }
+
+    // Check name
+    if (scopeName !== '*' && scopeName !== resourceName) {
+      return false;
+    }
+
+    // Check action
+    if (scopeAction !== '*' && scopeAction !== action) {
+      // Map action aliases
+      const actionAliases: Record<string, string[]> = {
+        read: ['pull', 'get'],
+        write: ['push', 'put', 'post'],
+      };
+
+      const aliases = actionAliases[scopeAction] || [];
+      if (!aliases.includes(action)) {
+        return false;
+      }
+    }
+
+    return true;
+  }
+
+  /**
+   * Convert unified scopes to OCI access array
+   */
+  private scopesToOciAccess(scopes: string[]): Array<{
+    type: string;
+    name: string;
+    actions: string[];
+  }> {
+    const access: Array<{type: string; name: string; actions: string[]}> = [];
+
+    for (const scope of scopes) {
+      const parts = scope.split(':');
+      if (parts.length >= 4 && parts[0] === 'oci') {
+        access.push({
+          type: parts[1],
+          name: parts[2],
+          actions: [parts[3]],
+        });
+      }
+    }
+
+    return access;
+  }
+
+  /**
+   * Convert OCI access array to unified scopes
+   */
+  private ociAccessToScopes(access: Array<{
+    type: string;
+    name: string;
+    actions: string[];
+  }>): string[] {
+    const scopes: string[] = [];
+
+    for (const item of access) {
+      for (const action of item.actions) {
+        scopes.push(`oci:${item.type}:${item.name}:${action}`);
+      }
+    }
+
+    return scopes;
+  }
+
+  /**
+   * Generate UUID for tokens
+   */
+  private generateUuid(): string {
+    return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, (c) => {
+      const r = (Math.random() * 16) | 0;
+      const v = c === 'x' ? r : (r & 0x3) | 0x8;
+      return v.toString(16);
+    });
+  }
+
+  /**
+   * Check if string is a valid UUID
+   */
+  private isValidUuid(str: string): boolean {
+    const uuidRegex = /^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i;
+    return uuidRegex.test(str);
+  }
+
+  /**
+   * Hash a token for identification
+   */
+  private hashToken(token: string): string {
+    return `sha512-${token.substring(0, 16)}...`;
+  }
+}

ts/core/classes.registrystorage.ts

@@ -1,17 +1,54 @@
 import * as plugins from '../plugins.js';
-import type { IStorageConfig, IStorageBackend } from './interfaces.core.js';
+import type { IStorageConfig, IStorageBackend, TRegistryProtocol } from './interfaces.core.js';
+import type {
+  IStorageHooks,
+  IStorageHookContext,
+  IStorageActor,
+  IStorageMetadata,
+} from './interfaces.storage.js';
 
 /**
- * Storage abstraction layer for registry
+ * Storage abstraction layer for registry.
- * Provides a unified interface over SmartBucket
+ * Provides a unified interface over SmartBucket with optional hooks
+ * for quota tracking, audit logging, cache invalidation, etc.
+ *
+ * @example
+ * ```typescript
+ * // Basic usage
+ * const storage = new RegistryStorage(config);
+ *
+ * // With hooks for quota tracking
+ * const storage = new RegistryStorage(config, {
+ *   beforePut: async (ctx) => {
+ *     const quota = await getQuota(ctx.actor?.orgId);
+ *     const usage = await getUsage(ctx.actor?.orgId);
+ *     if (usage + (ctx.metadata?.size || 0) > quota) {
+ *       return { allowed: false, reason: 'Quota exceeded' };
+ *     }
+ *     return { allowed: true };
+ *   },
+ *   afterPut: async (ctx) => {
+ *     await updateUsage(ctx.actor?.orgId, ctx.metadata?.size || 0);
+ *   }
+ * });
+ * ```
  */
 export class RegistryStorage implements IStorageBackend {
   private smartBucket: plugins.smartbucket.SmartBucket;
   private bucket: plugins.smartbucket.Bucket;
   private bucketName: string;
+  private hooks?: IStorageHooks;
 
-  constructor(private config: IStorageConfig) {
+  constructor(private config: IStorageConfig, hooks?: IStorageHooks) {
     this.bucketName = config.bucketName;
+    this.hooks = hooks;
+  }
+
+  /**
+   * Set storage hooks (can be called after construction)
+   */
+  public setHooks(hooks: IStorageHooks): void {
+    this.hooks = hooks;
   }
 
   /**
@@ -34,7 +71,24 @@ export class RegistryStorage implements IStorageBackend {
    */
   public async getObject(key: string): Promise<Buffer | null> {
     try {
-      return await this.bucket.fastGet({ path: key });
+      const data = await this.bucket.fastGet({ path: key });
+
+      // Call afterGet hook (non-blocking)
+      if (this.hooks?.afterGet && data) {
+        const context = this.currentContext;
+        if (context) {
+          this.hooks.afterGet({
+            operation: 'get',
+            key,
+            protocol: context.protocol,
+            actor: context.actor,
+            metadata: context.metadata,
+            timestamp: new Date(),
+          }).catch(() => {}); // Don't fail on hook errors
+        }
+      }
+
+      return data;
     } catch (error) {
       return null;
     }
@@ -48,19 +102,159 @@ export class RegistryStorage implements IStorageBackend {
     data: Buffer,
     metadata?: Record<string, string>
   ): Promise<void> {
+    // Call beforePut hook if available
+    if (this.hooks?.beforePut) {
+      const context = this.currentContext;
+      if (context) {
+        const hookContext: IStorageHookContext = {
+          operation: 'put',
+          key,
+          protocol: context.protocol,
+          actor: context.actor,
+          metadata: {
+            ...context.metadata,
+            size: data.length,
+          },
+          timestamp: new Date(),
+        };
+
+        const result = await this.hooks.beforePut(hookContext);
+        if (!result.allowed) {
+          throw new Error(result.reason || 'Storage operation denied by hook');
+        }
+      }
+    }
+
     // Note: SmartBucket doesn't support metadata yet
     await this.bucket.fastPut({
       path: key,
       contents: data,
       overwrite: true, // Always overwrite existing objects
     });
+
+    // Call afterPut hook (non-blocking)
+    if (this.hooks?.afterPut) {
+      const context = this.currentContext;
+      if (context) {
+        this.hooks.afterPut({
+          operation: 'put',
+          key,
+          protocol: context.protocol,
+          actor: context.actor,
+          metadata: {
+            ...context.metadata,
+            size: data.length,
+          },
+          timestamp: new Date(),
+        }).catch(() => {}); // Don't fail on hook errors
+      }
+    }
   }
 
   /**
    * Delete an object
    */
   public async deleteObject(key: string): Promise<void> {
+    // Call beforeDelete hook if available
+    if (this.hooks?.beforeDelete) {
+      const context = this.currentContext;
+      if (context) {
+        const hookContext: IStorageHookContext = {
+          operation: 'delete',
+          key,
+          protocol: context.protocol,
+          actor: context.actor,
+          metadata: context.metadata,
+          timestamp: new Date(),
+        };
+
+        const result = await this.hooks.beforeDelete(hookContext);
+        if (!result.allowed) {
+          throw new Error(result.reason || 'Delete operation denied by hook');
+        }
+      }
+    }
+
     await this.bucket.fastRemove({ path: key });
+
+    // Call afterDelete hook (non-blocking)
+    if (this.hooks?.afterDelete) {
+      const context = this.currentContext;
+      if (context) {
+        this.hooks.afterDelete({
+          operation: 'delete',
+          key,
+          protocol: context.protocol,
+          actor: context.actor,
+          metadata: context.metadata,
+          timestamp: new Date(),
+        }).catch(() => {}); // Don't fail on hook errors
+      }
+    }
+  }
+
+  // ========================================================================
+  // CONTEXT FOR HOOKS
+  // ========================================================================
+
+  /**
+   * Current operation context for hooks.
+   * Set this before performing storage operations to enable hooks.
+   */
+  private currentContext?: {
+    protocol: TRegistryProtocol;
+    actor?: IStorageActor;
+    metadata?: IStorageMetadata;
+  };
+
+  /**
+   * Set the current operation context for hooks.
+   * Call this before performing storage operations.
+   *
+   * @example
+   * ```typescript
+   * storage.setContext({
+   *   protocol: 'npm',
+   *   actor: { userId: 'user123', ip: '192.168.1.1' },
+   *   metadata: { packageName: 'lodash', version: '4.17.21' }
+   * });
+   * await storage.putNpmTarball('lodash', '4.17.21', tarball);
+   * storage.clearContext();
+   * ```
+   */
+  public setContext(context: {
+    protocol: TRegistryProtocol;
+    actor?: IStorageActor;
+    metadata?: IStorageMetadata;
+  }): void {
+    this.currentContext = context;
+  }
+
+  /**
+   * Clear the current operation context.
+   */
+  public clearContext(): void {
+    this.currentContext = undefined;
+  }
+
+  /**
+   * Execute a function with a temporary context.
+   * Context is automatically cleared after execution.
+   */
+  public async withContext<T>(
+    context: {
+      protocol: TRegistryProtocol;
+      actor?: IStorageActor;
+      metadata?: IStorageMetadata;
+    },
+    fn: () => Promise<T>
+  ): Promise<T> {
+    this.setContext(context);
+    try {
+      return await fn();
+    } finally {
+      this.clearContext();
+    }
   }
 
   /**

ts/core/index.ts

@@ -2,9 +2,16 @@
  * Core registry infrastructure exports
  */
 
-// Interfaces
+// Core interfaces
 export * from './interfaces.core.js';
 
+// Auth interfaces and provider
+export * from './interfaces.auth.js';
+export { DefaultAuthProvider } from './classes.defaultauthprovider.js';
+
+// Storage interfaces and hooks
+export * from './interfaces.storage.js';
+
 // Classes
 export { BaseRegistry } from './classes.baseregistry.js';
 export { RegistryStorage } from './classes.registrystorage.js';

ts/core/interfaces.auth.ts

@@ -0,0 +1,91 @@
+import type { IAuthToken, ICredentials, TRegistryProtocol } from './interfaces.core.js';
+
+/**
+ * Options for creating a token
+ */
+export interface ITokenOptions {
+  /** Whether the token is readonly */
+  readonly?: boolean;
+  /** Permission scopes */
+  scopes?: string[];
+  /** Expiration time in seconds */
+  expiresIn?: number;
+}
+
+/**
+ * Pluggable authentication provider interface.
+ * Implement this to integrate external auth systems (LDAP, OAuth, SSO, OIDC).
+ *
+ * @example
+ * ```typescript
+ * class LdapAuthProvider implements IAuthProvider {
+ *   constructor(private ldap: LdapClient, private redis: RedisClient) {}
+ *
+ *   async authenticate(credentials: ICredentials): Promise<string | null> {
+ *     return await this.ldap.bind(credentials.username, credentials.password);
+ *   }
+ *
+ *   async validateToken(token: string): Promise<IAuthToken | null> {
+ *     return await this.redis.get(`token:${token}`);
+ *   }
+ *   // ...
+ * }
+ * ```
+ */
+export interface IAuthProvider {
+  /**
+   * Initialize the auth provider (optional)
+   */
+  init?(): Promise<void>;
+
+  /**
+   * Authenticate user credentials (login flow)
+   * @param credentials - Username and password
+   * @returns User ID on success, null on failure
+   */
+  authenticate(credentials: ICredentials): Promise<string | null>;
+
+  /**
+   * Validate an existing token
+   * @param token - Token string (UUID or JWT)
+   * @param protocol - Optional protocol hint for optimization
+   * @returns Auth token info or null if invalid
+   */
+  validateToken(token: string, protocol?: TRegistryProtocol): Promise<IAuthToken | null>;
+
+  /**
+   * Create a new token for a user
+   * @param userId - User ID
+   * @param protocol - Protocol type (npm, oci, maven, etc.)
+   * @param options - Token options (readonly, scopes, expiration)
+   * @returns Token string
+   */
+  createToken(userId: string, protocol: TRegistryProtocol, options?: ITokenOptions): Promise<string>;
+
+  /**
+   * Revoke a token
+   * @param token - Token string to revoke
+   */
+  revokeToken(token: string): Promise<void>;
+
+  /**
+   * Check if user has permission for an action
+   * @param token - Auth token (or null for anonymous)
+   * @param resource - Resource being accessed (e.g., "npm:package:lodash")
+   * @param action - Action being performed (read, write, push, pull, delete)
+   * @returns true if authorized
+   */
+  authorize(token: IAuthToken | null, resource: string, action: string): Promise<boolean>;
+
+  /**
+   * List all tokens for a user (optional)
+   * @param userId - User ID
+   * @returns List of token info
+   */
+  listUserTokens?(userId: string): Promise<Array<{
+    key: string;
+    readonly: boolean;
+    created: string;
+    protocol?: TRegistryProtocol;
+  }>>;
+}

ts/core/interfaces.core.ts

@@ -3,6 +3,9 @@
  */
 
 import type * as plugins from '../plugins.js';
+import type { IProtocolUpstreamConfig } from '../upstream/interfaces.upstream.js';
+import type { IAuthProvider } from './interfaces.auth.js';
+import type { IStorageHooks } from './interfaces.storage.js';
 
 /**
  * Registry protocol types
@@ -86,6 +89,8 @@ export interface IProtocolConfig {
   enabled: boolean;
   basePath: string;
   features?: Record<string, boolean>;
+  /** Upstream registry configuration for proxying/caching */
+  upstream?: IProtocolUpstreamConfig;
 }
 
 /**
@@ -94,6 +99,20 @@ export interface IProtocolConfig {
 export interface IRegistryConfig {
   storage: IStorageConfig;
   auth: IAuthConfig;
+
+  /**
+   * Custom authentication provider.
+   * If not provided, uses the default in-memory auth provider.
+   * Implement IAuthProvider to integrate LDAP, OAuth, SSO, etc.
+   */
+  authProvider?: IAuthProvider;
+
+  /**
+   * Storage event hooks for quota tracking, audit logging, etc.
+   * Called before/after storage operations.
+   */
+  storageHooks?: IStorageHooks;
+
   oci?: IProtocolConfig;
   npm?: IProtocolConfig;
   maven?: IProtocolConfig;
@@ -149,6 +168,24 @@ export interface IRegistryError {
   }>;
 }
 
+/**
+ * Actor information - identifies who is performing the request
+ */
+export interface IRequestActor {
+  /** User ID (from validated token) */
+  userId?: string;
+  /** Token ID/hash for audit purposes */
+  tokenId?: string;
+  /** Client IP address */
+  ip?: string;
+  /** Client User-Agent */
+  userAgent?: string;
+  /** Organization ID (for multi-tenant setups) */
+  orgId?: string;
+  /** Session ID */
+  sessionId?: string;
+}
+
 /**
  * Base request context
  */
@@ -165,6 +202,11 @@ export interface IRequestContext {
    */
   rawBody?: Buffer;
   token?: string;
+  /**
+   * Actor information - identifies who is performing the request.
+   * Populated after authentication for audit logging, quota enforcement, etc.
+   */
+  actor?: IRequestActor;
 }
 
 /**

ts/core/interfaces.storage.ts

@@ -0,0 +1,130 @@
+import type { TRegistryProtocol } from './interfaces.core.js';
+
+/**
+ * Actor information from request context
+ */
+export interface IStorageActor {
+  userId?: string;
+  tokenId?: string;
+  ip?: string;
+  userAgent?: string;
+  orgId?: string;
+  sessionId?: string;
+}
+
+/**
+ * Metadata about the storage operation
+ */
+export interface IStorageMetadata {
+  /** Content type of the object */
+  contentType?: string;
+  /** Size in bytes */
+  size?: number;
+  /** Content digest (e.g., sha256:abc123) */
+  digest?: string;
+  /** Package/artifact name */
+  packageName?: string;
+  /** Version */
+  version?: string;
+}
+
+/**
+ * Context passed to storage hooks
+ */
+export interface IStorageHookContext {
+  /** Type of operation */
+  operation: 'put' | 'delete' | 'get';
+  /** Storage key/path */
+  key: string;
+  /** Protocol that triggered this operation */
+  protocol: TRegistryProtocol;
+  /** Actor who performed the operation (if known) */
+  actor?: IStorageActor;
+  /** Metadata about the object */
+  metadata?: IStorageMetadata;
+  /** Timestamp of the operation */
+  timestamp: Date;
+}
+
+/**
+ * Result from a beforePut hook that can modify the operation
+ */
+export interface IBeforePutResult {
+  /** Whether to allow the operation */
+  allowed: boolean;
+  /** Optional reason for rejection */
+  reason?: string;
+  /** Optional modified metadata */
+  metadata?: IStorageMetadata;
+}
+
+/**
+ * Result from a beforeDelete hook
+ */
+export interface IBeforeDeleteResult {
+  /** Whether to allow the operation */
+  allowed: boolean;
+  /** Optional reason for rejection */
+  reason?: string;
+}
+
+/**
+ * Storage event hooks for quota tracking, audit logging, cache invalidation, etc.
+ *
+ * @example
+ * ```typescript
+ * const quotaHooks: IStorageHooks = {
+ *   async beforePut(context) {
+ *     const quota = await getQuota(context.actor?.orgId);
+ *     const currentUsage = await getUsage(context.actor?.orgId);
+ *     if (currentUsage + (context.metadata?.size || 0) > quota) {
+ *       return { allowed: false, reason: 'Quota exceeded' };
+ *     }
+ *     return { allowed: true };
+ *   },
+ *
+ *   async afterPut(context) {
+ *     await updateUsage(context.actor?.orgId, context.metadata?.size || 0);
+ *     await auditLog('storage.put', context);
+ *   },
+ *
+ *   async afterDelete(context) {
+ *     await invalidateCache(context.key);
+ *   }
+ * };
+ * ```
+ */
+export interface IStorageHooks {
+  /**
+   * Called before storing an object.
+   * Return { allowed: false } to reject the operation.
+   * Use for quota checks, virus scanning, validation, etc.
+   */
+  beforePut?(context: IStorageHookContext): Promise<IBeforePutResult>;
+
+  /**
+   * Called after successfully storing an object.
+   * Use for quota tracking, audit logging, notifications, etc.
+   */
+  afterPut?(context: IStorageHookContext): Promise<void>;
+
+  /**
+   * Called before deleting an object.
+   * Return { allowed: false } to reject the operation.
+   * Use for preventing deletion of protected resources.
+   */
+  beforeDelete?(context: IStorageHookContext): Promise<IBeforeDeleteResult>;
+
+  /**
+   * Called after successfully deleting an object.
+   * Use for quota updates, audit logging, cache invalidation, etc.
+   */
+  afterDelete?(context: IStorageHookContext): Promise<void>;
+
+  /**
+   * Called after reading an object.
+   * Use for access logging, analytics, etc.
+   * Note: This is called even for cache hits.
+   */
+  afterGet?(context: IStorageHookContext): Promise<void>;
+}

ts/index.ts

@@ -9,6 +9,9 @@ export { SmartRegistry } from './classes.smartregistry.js';
 // Core infrastructure
 export * from './core/index.js';
 
+// Upstream infrastructure
+export * from './upstream/index.js';
+
 // OCI Registry
 export * from './oci/index.js';
 

ts/maven/classes.mavenregistry.ts

@@ -7,6 +7,7 @@ import { BaseRegistry } from '../core/classes.baseregistry.js';
 import type { RegistryStorage } from '../core/classes.registrystorage.js';
 import type { AuthManager } from '../core/classes.authmanager.js';
 import type { IRequestContext, IResponse, IAuthToken } from '../core/interfaces.core.js';
+import type { IProtocolUpstreamConfig } from '../upstream/interfaces.upstream.js';
 import { toBuffer } from '../core/helpers.buffer.js';
 import type { IMavenCoordinate, IMavenMetadata, IChecksums } from './interfaces.maven.js';
 import {
@@ -21,6 +22,7 @@ import {
   extractGAVFromPom,
   gavToPath,
 } from './helpers.maven.js';
+import { MavenUpstream } from './classes.mavenupstream.js';
 
 /**
  * Maven Registry class
@@ -31,18 +33,34 @@ export class MavenRegistry extends BaseRegistry {
   private authManager: AuthManager;
   private basePath: string = '/maven';
   private registryUrl: string;
+  private upstream: MavenUpstream | null = null;
 
   constructor(
     storage: RegistryStorage,
     authManager: AuthManager,
     basePath: string,
-    registryUrl: string
+    registryUrl: string,
+    upstreamConfig?: IProtocolUpstreamConfig
   ) {
     super();
     this.storage = storage;
     this.authManager = authManager;
     this.basePath = basePath;
     this.registryUrl = registryUrl;
+
+    // Initialize upstream if configured
+    if (upstreamConfig?.enabled) {
+      this.upstream = new MavenUpstream(upstreamConfig);
+    }
+  }
+
+  /**
+   * Clean up resources (timers, connections, etc.)
+   */
+  public destroy(): void {
+    if (this.upstream) {
+      this.upstream.stop();
+    }
   }
 
   public async init(): Promise<void> {
@@ -234,7 +252,23 @@ export class MavenRegistry extends BaseRegistry {
     version: string,
     filename: string
   ): Promise<IResponse> {
-    const data = await this.storage.getMavenArtifact(groupId, artifactId, version, filename);
+    let data = await this.storage.getMavenArtifact(groupId, artifactId, version, filename);
+
+    // Try upstream if not found locally
+    if (!data && this.upstream) {
+      // Parse the filename to extract extension and classifier
+      const { extension, classifier } = this.parseFilename(filename, artifactId, version);
+      if (extension) {
+        data = await this.upstream.fetchArtifact(groupId, artifactId, version, extension, classifier);
+        if (data) {
+          // Cache the artifact locally
+          await this.storage.putMavenArtifact(groupId, artifactId, version, filename, data);
+          // Generate and store checksums
+          const checksums = await calculateChecksums(data);
+          await this.storeChecksums(groupId, artifactId, version, filename, checksums);
+        }
+      }
+    }
 
     if (!data) {
       return {
@@ -462,7 +496,17 @@ export class MavenRegistry extends BaseRegistry {
   // ========================================================================
 
   private async getMetadata(groupId: string, artifactId: string): Promise<IResponse> {
-    const metadataBuffer = await this.storage.getMavenMetadata(groupId, artifactId);
+    let metadataBuffer = await this.storage.getMavenMetadata(groupId, artifactId);
+
+    // Try upstream if not found locally
+    if (!metadataBuffer && this.upstream) {
+      const upstreamMetadata = await this.upstream.fetchMetadata(groupId, artifactId);
+      if (upstreamMetadata) {
+        metadataBuffer = Buffer.from(upstreamMetadata, 'utf-8');
+        // Cache the metadata locally
+        await this.storage.putMavenMetadata(groupId, artifactId, metadataBuffer);
+      }
+    }
 
     if (!metadataBuffer) {
       // Generate empty metadata if none exists
@@ -578,4 +622,41 @@ export class MavenRegistry extends BaseRegistry {
 
     return contentTypes[extension] || 'application/octet-stream';
   }
+
+  /**
+   * Parse a Maven filename to extract extension and classifier.
+   * Filename format: {artifactId}-{version}[-{classifier}].{extension}
+   */
+  private parseFilename(
+    filename: string,
+    artifactId: string,
+    version: string
+  ): { extension: string; classifier?: string } {
+    const prefix = `${artifactId}-${version}`;
+
+    if (!filename.startsWith(prefix)) {
+      // Fallback: just get the extension
+      const lastDot = filename.lastIndexOf('.');
+      return { extension: lastDot > 0 ? filename.slice(lastDot + 1) : '' };
+    }
+
+    const remainder = filename.slice(prefix.length);
+    // remainder is either ".extension" or "-classifier.extension"
+
+    if (remainder.startsWith('.')) {
+      return { extension: remainder.slice(1) };
+    }
+
+    if (remainder.startsWith('-')) {
+      const lastDot = remainder.lastIndexOf('.');
+      if (lastDot > 1) {
+        return {
+          classifier: remainder.slice(1, lastDot),
+          extension: remainder.slice(lastDot + 1),
+        };
+      }
+    }
+
+    return { extension: '' };
+  }
 }

ts/maven/classes.mavenupstream.ts

@@ -0,0 +1,220 @@
+import * as plugins from '../plugins.js';
+import { BaseUpstream } from '../upstream/classes.baseupstream.js';
+import type {
+  IProtocolUpstreamConfig,
+  IUpstreamFetchContext,
+  IUpstreamRegistryConfig,
+} from '../upstream/interfaces.upstream.js';
+import type { IMavenCoordinate } from './interfaces.maven.js';
+
+/**
+ * Maven-specific upstream implementation.
+ *
+ * Handles:
+ * - Artifact fetching (JAR, POM, WAR, etc.)
+ * - Metadata fetching (maven-metadata.xml)
+ * - Checksum files (.md5, .sha1, .sha256, .sha512)
+ * - SNAPSHOT version handling
+ * - Content-addressable caching for release artifacts
+ */
+export class MavenUpstream extends BaseUpstream {
+  protected readonly protocolName = 'maven';
+
+  constructor(
+    config: IProtocolUpstreamConfig,
+    logger?: plugins.smartlog.Smartlog,
+  ) {
+    super(config, logger);
+  }
+
+  /**
+   * Fetch an artifact from upstream registries.
+   */
+  public async fetchArtifact(
+    groupId: string,
+    artifactId: string,
+    version: string,
+    extension: string,
+    classifier?: string,
+  ): Promise<Buffer | null> {
+    const path = this.buildArtifactPath(groupId, artifactId, version, extension, classifier);
+    const resource = `${groupId}:${artifactId}`;
+
+    const context: IUpstreamFetchContext = {
+      protocol: 'maven',
+      resource,
+      resourceType: 'artifact',
+      path,
+      method: 'GET',
+      headers: {},
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    return Buffer.isBuffer(result.body) ? result.body : Buffer.from(result.body);
+  }
+
+  /**
+   * Fetch maven-metadata.xml from upstream.
+   */
+  public async fetchMetadata(groupId: string, artifactId: string, version?: string): Promise<string | null> {
+    const groupPath = groupId.replace(/\./g, '/');
+    let path: string;
+
+    if (version) {
+      // Version-level metadata (for SNAPSHOTs)
+      path = `/${groupPath}/${artifactId}/${version}/maven-metadata.xml`;
+    } else {
+      // Artifact-level metadata (lists all versions)
+      path = `/${groupPath}/${artifactId}/maven-metadata.xml`;
+    }
+
+    const resource = `${groupId}:${artifactId}`;
+
+    const context: IUpstreamFetchContext = {
+      protocol: 'maven',
+      resource,
+      resourceType: 'metadata',
+      path,
+      method: 'GET',
+      headers: {
+        'accept': 'application/xml, text/xml',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    if (Buffer.isBuffer(result.body)) {
+      return result.body.toString('utf8');
+    }
+
+    return typeof result.body === 'string' ? result.body : null;
+  }
+
+  /**
+   * Fetch a checksum file from upstream.
+   */
+  public async fetchChecksum(
+    groupId: string,
+    artifactId: string,
+    version: string,
+    extension: string,
+    checksumType: 'md5' | 'sha1' | 'sha256' | 'sha512',
+    classifier?: string,
+  ): Promise<string | null> {
+    const basePath = this.buildArtifactPath(groupId, artifactId, version, extension, classifier);
+    const path = `${basePath}.${checksumType}`;
+    const resource = `${groupId}:${artifactId}`;
+
+    const context: IUpstreamFetchContext = {
+      protocol: 'maven',
+      resource,
+      resourceType: 'checksum',
+      path,
+      method: 'GET',
+      headers: {
+        'accept': 'text/plain',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    if (Buffer.isBuffer(result.body)) {
+      return result.body.toString('utf8').trim();
+    }
+
+    return typeof result.body === 'string' ? result.body.trim() : null;
+  }
+
+  /**
+   * Check if an artifact exists in upstream (HEAD request).
+   */
+  public async headArtifact(
+    groupId: string,
+    artifactId: string,
+    version: string,
+    extension: string,
+    classifier?: string,
+  ): Promise<{ exists: boolean; size?: number; lastModified?: string } | null> {
+    const path = this.buildArtifactPath(groupId, artifactId, version, extension, classifier);
+    const resource = `${groupId}:${artifactId}`;
+
+    const context: IUpstreamFetchContext = {
+      protocol: 'maven',
+      resource,
+      resourceType: 'artifact',
+      path,
+      method: 'HEAD',
+      headers: {},
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result) {
+      return null;
+    }
+
+    if (!result.success) {
+      return { exists: false };
+    }
+
+    return {
+      exists: true,
+      size: result.headers['content-length'] ? parseInt(result.headers['content-length'], 10) : undefined,
+      lastModified: result.headers['last-modified'],
+    };
+  }
+
+  /**
+   * Build the path for a Maven artifact.
+   */
+  private buildArtifactPath(
+    groupId: string,
+    artifactId: string,
+    version: string,
+    extension: string,
+    classifier?: string,
+  ): string {
+    const groupPath = groupId.replace(/\./g, '/');
+    let filename = `${artifactId}-${version}`;
+    if (classifier) {
+      filename += `-${classifier}`;
+    }
+    filename += `.${extension}`;
+
+    return `/${groupPath}/${artifactId}/${version}/${filename}`;
+  }
+
+  /**
+   * Override URL building for Maven-specific handling.
+   */
+  protected buildUpstreamUrl(
+    upstream: IUpstreamRegistryConfig,
+    context: IUpstreamFetchContext,
+  ): string {
+    let baseUrl = upstream.url;
+
+    // Remove trailing slash
+    if (baseUrl.endsWith('/')) {
+      baseUrl = baseUrl.slice(0, -1);
+    }
+
+    return `${baseUrl}${context.path}`;
+  }
+}

ts/maven/index.ts

@@ -3,5 +3,6 @@
  */
 
 export { MavenRegistry } from './classes.mavenregistry.js';
+export { MavenUpstream } from './classes.mavenupstream.js';
 export * from './interfaces.maven.js';
 export * from './helpers.maven.js';

ts/npm/classes.npmregistry.ts

@@ -3,6 +3,8 @@ import { BaseRegistry } from '../core/classes.baseregistry.js';
 import { RegistryStorage } from '../core/classes.registrystorage.js';
 import { AuthManager } from '../core/classes.authmanager.js';
 import type { IRequestContext, IResponse, IAuthToken } from '../core/interfaces.core.js';
+import type { IProtocolUpstreamConfig } from '../upstream/interfaces.upstream.js';
+import { NpmUpstream } from './classes.npmupstream.js';
 import type {
   IPackument,
   INpmVersion,
@@ -25,12 +27,14 @@ export class NpmRegistry extends BaseRegistry {
   private basePath: string = '/npm';
   private registryUrl: string;
   private logger: Smartlog;
+  private upstream: NpmUpstream | null = null;
 
   constructor(
     storage: RegistryStorage,
     authManager: AuthManager,
     basePath: string = '/npm',
-    registryUrl: string = 'http://localhost:5000/npm'
+    registryUrl: string = 'http://localhost:5000/npm',
+    upstreamConfig?: IProtocolUpstreamConfig
   ) {
     super();
     this.storage = storage;
@@ -50,6 +54,14 @@ export class NpmRegistry extends BaseRegistry {
       }
     });
     this.logger.enableConsole();
+
+    // Initialize upstream if configured
+    if (upstreamConfig?.enabled) {
+      this.upstream = new NpmUpstream(upstreamConfig, registryUrl, this.logger);
+      this.logger.log('info', 'NPM upstream initialized', {
+        upstreams: upstreamConfig.upstreams.map(u => u.name),
+      });
+    }
   }
 
   public async init(): Promise<void> {
@@ -209,13 +221,28 @@ export class NpmRegistry extends BaseRegistry {
     token: IAuthToken | null,
     query: Record<string, string>
   ): Promise<IResponse> {
-    const packument = await this.storage.getNpmPackument(packageName);
+    let packument = await this.storage.getNpmPackument(packageName);
     this.logger.log('debug', `getPackument: ${packageName}`, {
       packageName,
       found: !!packument,
       versions: packument ? Object.keys(packument.versions).length : 0
     });
 
+    // If not found locally, try upstream
+    if (!packument && this.upstream) {
+      this.logger.log('debug', `getPackument: fetching from upstream`, { packageName });
+      const upstreamPackument = await this.upstream.fetchPackument(packageName);
+      if (upstreamPackument) {
+        this.logger.log('debug', `getPackument: found in upstream`, {
+          packageName,
+          versions: Object.keys(upstreamPackument.versions || {}).length
+        });
+        packument = upstreamPackument;
+        // Optionally cache the packument locally (without tarballs)
+        // We don't store tarballs here - they'll be fetched on demand
+      }
+    }
+
     if (!packument) {
       return {
         status: 404,
@@ -255,11 +282,21 @@ export class NpmRegistry extends BaseRegistry {
     token: IAuthToken | null
   ): Promise<IResponse> {
     this.logger.log('debug', 'handlePackageVersion', { packageName, version });
-    const packument = await this.storage.getNpmPackument(packageName);
+    let packument = await this.storage.getNpmPackument(packageName);
     this.logger.log('debug', 'handlePackageVersion packument', { found: !!packument });
     if (packument) {
       this.logger.log('debug', 'handlePackageVersion versions', { versions: Object.keys(packument.versions || {}) });
     }
+
+    // If not found locally, try upstream
+    if (!packument && this.upstream) {
+      this.logger.log('debug', 'handlePackageVersion: fetching from upstream', { packageName });
+      const upstreamPackument = await this.upstream.fetchPackument(packageName);
+      if (upstreamPackument) {
+        packument = upstreamPackument;
+      }
+    }
+
     if (!packument) {
       return {
         status: 404,
@@ -529,7 +566,7 @@ export class NpmRegistry extends BaseRegistry {
     token: IAuthToken | null
   ): Promise<IResponse> {
     // Extract version from filename: package-name-1.0.0.tgz
-    const versionMatch = filename.match(/-([\d.]+(?:-[a-z0-9.]+)?)\.tgz$/);
+    const versionMatch = filename.match(/-([\d.]+(?:-[a-z0-9.]+)?)\.tgz$/i);
     if (!versionMatch) {
       return {
         status: 400,
@@ -539,7 +576,26 @@ export class NpmRegistry extends BaseRegistry {
     }
 
     const version = versionMatch[1];
-    const tarball = await this.storage.getNpmTarball(packageName, version);
+    let tarball = await this.storage.getNpmTarball(packageName, version);
+
+    // If not found locally, try upstream
+    if (!tarball && this.upstream) {
+      this.logger.log('debug', 'handleTarballDownload: fetching from upstream', {
+        packageName,
+        version,
+      });
+      const upstreamTarball = await this.upstream.fetchTarball(packageName, version);
+      if (upstreamTarball) {
+        tarball = upstreamTarball;
+        // Cache the tarball locally for future requests
+        await this.storage.putNpmTarball(packageName, version, tarball);
+        this.logger.log('debug', 'handleTarballDownload: cached tarball locally', {
+          packageName,
+          version,
+          size: tarball.length,
+        });
+      }
+    }
 
     if (!tarball) {
       return {

ts/npm/classes.npmupstream.ts

@@ -0,0 +1,260 @@
+import * as plugins from '../plugins.js';
+import { BaseUpstream } from '../upstream/classes.baseupstream.js';
+import type {
+  IProtocolUpstreamConfig,
+  IUpstreamFetchContext,
+  IUpstreamResult,
+  IUpstreamRegistryConfig,
+} from '../upstream/interfaces.upstream.js';
+import type { IPackument, INpmVersion } from './interfaces.npm.js';
+
+/**
+ * NPM-specific upstream implementation.
+ *
+ * Handles:
+ * - Package metadata (packument) fetching
+ * - Tarball proxying
+ * - Scoped package routing (@scope/* patterns)
+ * - NPM-specific URL rewriting
+ */
+export class NpmUpstream extends BaseUpstream {
+  protected readonly protocolName = 'npm';
+
+  /** Local registry URL for rewriting tarball URLs */
+  private readonly localRegistryUrl: string;
+
+  constructor(
+    config: IProtocolUpstreamConfig,
+    localRegistryUrl: string,
+    logger?: plugins.smartlog.Smartlog,
+  ) {
+    super(config, logger);
+    this.localRegistryUrl = localRegistryUrl;
+  }
+
+  /**
+   * Fetch a packument from upstream registries.
+   */
+  public async fetchPackument(packageName: string): Promise<IPackument | null> {
+    const context: IUpstreamFetchContext = {
+      protocol: 'npm',
+      resource: packageName,
+      resourceType: 'packument',
+      path: `/${encodeURIComponent(packageName).replace('%40', '@')}`,
+      method: 'GET',
+      headers: {
+        'accept': 'application/json',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    // Parse and process packument
+    let packument: IPackument;
+    if (Buffer.isBuffer(result.body)) {
+      packument = JSON.parse(result.body.toString('utf8'));
+    } else {
+      packument = result.body;
+    }
+
+    // Rewrite tarball URLs to point to local registry
+    packument = this.rewriteTarballUrls(packument);
+
+    return packument;
+  }
+
+  /**
+   * Fetch a specific version from upstream registries.
+   */
+  public async fetchVersion(packageName: string, version: string): Promise<INpmVersion | null> {
+    const context: IUpstreamFetchContext = {
+      protocol: 'npm',
+      resource: packageName,
+      resourceType: 'version',
+      path: `/${encodeURIComponent(packageName).replace('%40', '@')}/${version}`,
+      method: 'GET',
+      headers: {
+        'accept': 'application/json',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    let versionData: INpmVersion;
+    if (Buffer.isBuffer(result.body)) {
+      versionData = JSON.parse(result.body.toString('utf8'));
+    } else {
+      versionData = result.body;
+    }
+
+    // Rewrite tarball URL
+    if (versionData.dist?.tarball) {
+      versionData.dist.tarball = this.rewriteSingleTarballUrl(
+        packageName,
+        versionData.version,
+        versionData.dist.tarball,
+      );
+    }
+
+    return versionData;
+  }
+
+  /**
+   * Fetch a tarball from upstream registries.
+   */
+  public async fetchTarball(packageName: string, version: string): Promise<Buffer | null> {
+    // First, try to get the tarball URL from packument
+    const packument = await this.fetchPackument(packageName);
+    let tarballPath: string;
+
+    if (packument?.versions?.[version]?.dist?.tarball) {
+      // Extract path from original (upstream) tarball URL
+      const tarballUrl = packument.versions[version].dist.tarball;
+      try {
+        const url = new URL(tarballUrl);
+        tarballPath = url.pathname;
+      } catch {
+        // Fallback to standard NPM tarball path
+        tarballPath = this.buildTarballPath(packageName, version);
+      }
+    } else {
+      tarballPath = this.buildTarballPath(packageName, version);
+    }
+
+    const context: IUpstreamFetchContext = {
+      protocol: 'npm',
+      resource: packageName,
+      resourceType: 'tarball',
+      path: tarballPath,
+      method: 'GET',
+      headers: {
+        'accept': 'application/octet-stream',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    return Buffer.isBuffer(result.body) ? result.body : Buffer.from(result.body);
+  }
+
+  /**
+   * Search packages in upstream registries.
+   */
+  public async search(text: string, size: number = 20, from: number = 0): Promise<any | null> {
+    const context: IUpstreamFetchContext = {
+      protocol: 'npm',
+      resource: '*',
+      resourceType: 'search',
+      path: '/-/v1/search',
+      method: 'GET',
+      headers: {
+        'accept': 'application/json',
+      },
+      query: {
+        text,
+        size: size.toString(),
+        from: from.toString(),
+      },
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    if (Buffer.isBuffer(result.body)) {
+      return JSON.parse(result.body.toString('utf8'));
+    }
+
+    return result.body;
+  }
+
+  /**
+   * Build the standard NPM tarball path.
+   */
+  private buildTarballPath(packageName: string, version: string): string {
+    // NPM uses: /{package}/-/{package-name}-{version}.tgz
+    // For scoped packages: /@scope/name/-/name-version.tgz
+    if (packageName.startsWith('@')) {
+      const [scope, name] = packageName.split('/');
+      return `/${scope}/${name}/-/${name}-${version}.tgz`;
+    } else {
+      return `/${packageName}/-/${packageName}-${version}.tgz`;
+    }
+  }
+
+  /**
+   * Rewrite all tarball URLs in a packument to point to local registry.
+   */
+  private rewriteTarballUrls(packument: IPackument): IPackument {
+    if (!packument.versions) {
+      return packument;
+    }
+
+    const rewritten = { ...packument };
+    rewritten.versions = {};
+
+    for (const [version, versionData] of Object.entries(packument.versions)) {
+      const newVersionData = { ...versionData };
+      if (newVersionData.dist?.tarball) {
+        newVersionData.dist = {
+          ...newVersionData.dist,
+          tarball: this.rewriteSingleTarballUrl(
+            packument.name,
+            version,
+            newVersionData.dist.tarball,
+          ),
+        };
+      }
+      rewritten.versions[version] = newVersionData;
+    }
+
+    return rewritten;
+  }
+
+  /**
+   * Rewrite a single tarball URL to point to local registry.
+   */
+  private rewriteSingleTarballUrl(
+    packageName: string,
+    version: string,
+    _originalUrl: string,
+  ): string {
+    // Generate local tarball URL
+    // Format: {localRegistryUrl}/{package}/-/{package-name}-{version}.tgz
+    const safeName = packageName.replace('@', '').replace('/', '-');
+    return `${this.localRegistryUrl}/${packageName}/-/${safeName}-${version}.tgz`;
+  }
+
+  /**
+   * Override URL building for NPM-specific handling.
+   */
+  protected buildUpstreamUrl(
+    upstream: IUpstreamRegistryConfig,
+    context: IUpstreamFetchContext,
+  ): string {
+    // NPM registries often don't have trailing slashes
+    let baseUrl = upstream.url;
+    if (baseUrl.endsWith('/')) {
+      baseUrl = baseUrl.slice(0, -1);
+    }
+
+    return `${baseUrl}${context.path}`;
+  }
+}

ts/npm/index.ts

@@ -3,4 +3,5 @@
  */
 
 export { NpmRegistry } from './classes.npmregistry.js';
+export { NpmUpstream } from './classes.npmupstream.js';
 export * from './interfaces.npm.js';

ts/oci/classes.ociregistry.ts

@@ -1,7 +1,10 @@
+import { Smartlog } from '@push.rocks/smartlog';
 import { BaseRegistry } from '../core/classes.baseregistry.js';
 import { RegistryStorage } from '../core/classes.registrystorage.js';
 import { AuthManager } from '../core/classes.authmanager.js';
 import type { IRequestContext, IResponse, IAuthToken, IRegistryError } from '../core/interfaces.core.js';
+import type { IProtocolUpstreamConfig } from '../upstream/interfaces.upstream.js';
+import { OciUpstream } from './classes.ociupstream.js';
 import type {
   IUploadSession,
   IOciManifest,
@@ -21,18 +24,42 @@ export class OciRegistry extends BaseRegistry {
   private basePath: string = '/oci';
   private cleanupInterval?: NodeJS.Timeout;
   private ociTokens?: { realm: string; service: string };
+  private upstream: OciUpstream | null = null;
+  private logger: Smartlog;
 
   constructor(
     storage: RegistryStorage,
     authManager: AuthManager,
     basePath: string = '/oci',
-    ociTokens?: { realm: string; service: string }
+    ociTokens?: { realm: string; service: string },
+    upstreamConfig?: IProtocolUpstreamConfig
   ) {
     super();
     this.storage = storage;
     this.authManager = authManager;
     this.basePath = basePath;
     this.ociTokens = ociTokens;
+
+    // Initialize logger
+    this.logger = new Smartlog({
+      logContext: {
+        company: 'push.rocks',
+        companyunit: 'smartregistry',
+        containerName: 'oci-registry',
+        environment: (process.env.NODE_ENV as any) || 'development',
+        runtime: 'node',
+        zone: 'oci'
+      }
+    });
+    this.logger.enableConsole();
+
+    // Initialize upstream if configured
+    if (upstreamConfig?.enabled) {
+      this.upstream = new OciUpstream(upstreamConfig, basePath, this.logger);
+      this.logger.log('info', 'OCI upstream initialized', {
+        upstreams: upstreamConfig.upstreams.map(u => u.name),
+      });
+    }
   }
 
   public async init(): Promise<void> {
@@ -302,16 +329,50 @@ export class OciRegistry extends BaseRegistry {
     if (!reference.startsWith('sha256:')) {
       const tags = await this.getTagsData(repository);
       digest = tags[reference];
-      if (!digest) {
+    }
-        return {
+
-          status: 404,
+    // Try local storage first (if we have a digest)
-          headers: {},
+    let manifestData: Buffer | null = null;
-          body: this.createError('MANIFEST_UNKNOWN', 'Manifest not found'),
+    let contentType: string | null = null;
-        };
+
+    if (digest) {
+      manifestData = await this.storage.getOciManifest(repository, digest);
+      if (manifestData) {
+        contentType = await this.storage.getOciManifestContentType(repository, digest);
+        if (!contentType) {
+          contentType = this.detectManifestContentType(manifestData);
+        }
+      }
+    }
+
+    // If not found locally, try upstream
+    if (!manifestData && this.upstream) {
+      this.logger.log('debug', 'getManifest: fetching from upstream', { repository, reference });
+      const upstreamResult = await this.upstream.fetchManifest(repository, reference);
+      if (upstreamResult) {
+        manifestData = Buffer.from(JSON.stringify(upstreamResult.manifest), 'utf8');
+        contentType = upstreamResult.contentType;
+        digest = upstreamResult.digest;
+
+        // Cache the manifest locally
+        await this.storage.putOciManifest(repository, digest, manifestData, contentType);
+
+        // If reference is a tag, update tags mapping
+        if (!reference.startsWith('sha256:')) {
+          const tags = await this.getTagsData(repository);
+          tags[reference] = digest;
+          const tagsPath = `oci/tags/${repository}/tags.json`;
+          await this.storage.putObject(tagsPath, Buffer.from(JSON.stringify(tags), 'utf-8'));
+        }
+
+        this.logger.log('debug', 'getManifest: cached manifest locally', {
+          repository,
+          reference,
+          digest,
+        });
       }
     }
 
-    const manifestData = await this.storage.getOciManifest(repository, digest);
     if (!manifestData) {
       return {
         status: 404,
@@ -320,17 +381,10 @@ export class OciRegistry extends BaseRegistry {
       };
     }
 
-    // Get stored content type, falling back to detecting from manifest content
-    let contentType = await this.storage.getOciManifestContentType(repository, digest);
-    if (!contentType) {
-      // Fallback: detect content type from manifest content
-      contentType = this.detectManifestContentType(manifestData);
-    }
-
     return {
       status: 200,
       headers: {
-        'Content-Type': contentType,
+        'Content-Type': contentType || 'application/vnd.oci.image.manifest.v1+json',
         'Docker-Content-Digest': digest,
       },
       body: manifestData,
@@ -466,7 +520,25 @@ export class OciRegistry extends BaseRegistry {
       return this.createUnauthorizedResponse(repository, 'pull');
     }
 
-    const data = await this.storage.getOciBlob(digest);
+    // Try local storage first
+    let data = await this.storage.getOciBlob(digest);
+
+    // If not found locally, try upstream
+    if (!data && this.upstream) {
+      this.logger.log('debug', 'getBlob: fetching from upstream', { repository, digest });
+      const upstreamBlob = await this.upstream.fetchBlob(repository, digest);
+      if (upstreamBlob) {
+        data = upstreamBlob;
+        // Cache the blob locally (blobs are content-addressable and immutable)
+        await this.storage.putOciBlob(digest, data);
+        this.logger.log('debug', 'getBlob: cached blob locally', {
+          repository,
+          digest,
+          size: data.length,
+        });
+      }
+    }
+
     if (!data) {
       return {
         status: 404,

ts/oci/classes.ociupstream.ts

@@ -0,0 +1,263 @@
+import * as plugins from '../plugins.js';
+import { BaseUpstream } from '../upstream/classes.baseupstream.js';
+import type {
+  IProtocolUpstreamConfig,
+  IUpstreamFetchContext,
+  IUpstreamResult,
+  IUpstreamRegistryConfig,
+} from '../upstream/interfaces.upstream.js';
+import type { IOciManifest, IOciImageIndex, ITagList } from './interfaces.oci.js';
+
+/**
+ * OCI-specific upstream implementation.
+ *
+ * Handles:
+ * - Manifest fetching (image manifests and index manifests)
+ * - Blob proxying (layers, configs)
+ * - Tag list fetching
+ * - Content-addressable caching (blobs are immutable)
+ * - Docker Hub authentication flow
+ */
+export class OciUpstream extends BaseUpstream {
+  protected readonly protocolName = 'oci';
+
+  /** Local registry base path for URL building */
+  private readonly localBasePath: string;
+
+  constructor(
+    config: IProtocolUpstreamConfig,
+    localBasePath: string = '/oci',
+    logger?: plugins.smartlog.Smartlog,
+  ) {
+    super(config, logger);
+    this.localBasePath = localBasePath;
+  }
+
+  /**
+   * Fetch a manifest from upstream registries.
+   */
+  public async fetchManifest(
+    repository: string,
+    reference: string,
+  ): Promise<{ manifest: IOciManifest | IOciImageIndex; contentType: string; digest: string } | null> {
+    const context: IUpstreamFetchContext = {
+      protocol: 'oci',
+      resource: repository,
+      resourceType: 'manifest',
+      path: `/v2/${repository}/manifests/${reference}`,
+      method: 'GET',
+      headers: {
+        'accept': [
+          'application/vnd.oci.image.manifest.v1+json',
+          'application/vnd.oci.image.index.v1+json',
+          'application/vnd.docker.distribution.manifest.v2+json',
+          'application/vnd.docker.distribution.manifest.list.v2+json',
+          'application/vnd.docker.distribution.manifest.v1+json',
+        ].join(', '),
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    let manifest: IOciManifest | IOciImageIndex;
+    if (Buffer.isBuffer(result.body)) {
+      manifest = JSON.parse(result.body.toString('utf8'));
+    } else {
+      manifest = result.body;
+    }
+
+    const contentType = result.headers['content-type'] || 'application/vnd.oci.image.manifest.v1+json';
+    const digest = result.headers['docker-content-digest'] || '';
+
+    return { manifest, contentType, digest };
+  }
+
+  /**
+   * Check if a manifest exists in upstream (HEAD request).
+   */
+  public async headManifest(
+    repository: string,
+    reference: string,
+  ): Promise<{ exists: boolean; contentType?: string; digest?: string; size?: number } | null> {
+    const context: IUpstreamFetchContext = {
+      protocol: 'oci',
+      resource: repository,
+      resourceType: 'manifest',
+      path: `/v2/${repository}/manifests/${reference}`,
+      method: 'HEAD',
+      headers: {
+        'accept': [
+          'application/vnd.oci.image.manifest.v1+json',
+          'application/vnd.oci.image.index.v1+json',
+          'application/vnd.docker.distribution.manifest.v2+json',
+          'application/vnd.docker.distribution.manifest.list.v2+json',
+        ].join(', '),
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result) {
+      return null;
+    }
+
+    if (!result.success) {
+      return { exists: false };
+    }
+
+    return {
+      exists: true,
+      contentType: result.headers['content-type'],
+      digest: result.headers['docker-content-digest'],
+      size: result.headers['content-length'] ? parseInt(result.headers['content-length'], 10) : undefined,
+    };
+  }
+
+  /**
+   * Fetch a blob from upstream registries.
+   */
+  public async fetchBlob(repository: string, digest: string): Promise<Buffer | null> {
+    const context: IUpstreamFetchContext = {
+      protocol: 'oci',
+      resource: repository,
+      resourceType: 'blob',
+      path: `/v2/${repository}/blobs/${digest}`,
+      method: 'GET',
+      headers: {
+        'accept': 'application/octet-stream',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    return Buffer.isBuffer(result.body) ? result.body : Buffer.from(result.body);
+  }
+
+  /**
+   * Check if a blob exists in upstream (HEAD request).
+   */
+  public async headBlob(
+    repository: string,
+    digest: string,
+  ): Promise<{ exists: boolean; size?: number } | null> {
+    const context: IUpstreamFetchContext = {
+      protocol: 'oci',
+      resource: repository,
+      resourceType: 'blob',
+      path: `/v2/${repository}/blobs/${digest}`,
+      method: 'HEAD',
+      headers: {},
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result) {
+      return null;
+    }
+
+    if (!result.success) {
+      return { exists: false };
+    }
+
+    return {
+      exists: true,
+      size: result.headers['content-length'] ? parseInt(result.headers['content-length'], 10) : undefined,
+    };
+  }
+
+  /**
+   * Fetch the tag list for a repository.
+   */
+  public async fetchTags(repository: string, n?: number, last?: string): Promise<ITagList | null> {
+    const query: Record<string, string> = {};
+    if (n) query.n = n.toString();
+    if (last) query.last = last;
+
+    const context: IUpstreamFetchContext = {
+      protocol: 'oci',
+      resource: repository,
+      resourceType: 'tags',
+      path: `/v2/${repository}/tags/list`,
+      method: 'GET',
+      headers: {
+        'accept': 'application/json',
+      },
+      query,
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    let tagList: ITagList;
+    if (Buffer.isBuffer(result.body)) {
+      tagList = JSON.parse(result.body.toString('utf8'));
+    } else {
+      tagList = result.body;
+    }
+
+    return tagList;
+  }
+
+  /**
+   * Override URL building for OCI-specific handling.
+   * OCI registries use /v2/ prefix and may require special handling for Docker Hub.
+   */
+  protected buildUpstreamUrl(
+    upstream: IUpstreamRegistryConfig,
+    context: IUpstreamFetchContext,
+  ): string {
+    let baseUrl = upstream.url;
+
+    // Remove trailing slash
+    if (baseUrl.endsWith('/')) {
+      baseUrl = baseUrl.slice(0, -1);
+    }
+
+    // Handle Docker Hub special case
+    // Docker Hub uses registry-1.docker.io but library images need special handling
+    if (baseUrl.includes('docker.io') || baseUrl.includes('registry-1.docker.io')) {
+      // For library images (e.g., "nginx" -> "library/nginx")
+      const pathParts = context.path.match(/^\/v2\/([^\/]+)\/(.+)$/);
+      if (pathParts) {
+        const [, repository, rest] = pathParts;
+        // If repository doesn't contain a slash, it's a library image
+        if (!repository.includes('/')) {
+          return `${baseUrl}/v2/library/${repository}/${rest}`;
+        }
+      }
+    }
+
+    return `${baseUrl}${context.path}`;
+  }
+
+  /**
+   * Override header building for OCI-specific authentication.
+   * OCI registries may require token-based auth obtained from a separate endpoint.
+   */
+  protected buildHeaders(
+    upstream: IUpstreamRegistryConfig,
+    context: IUpstreamFetchContext,
+  ): Record<string, string> {
+    const headers = super.buildHeaders(upstream, context);
+
+    // OCI registries typically use Docker-Distribution-API-Version header
+    headers['docker-distribution-api-version'] = 'registry/2.0';
+
+    return headers;
+  }
+}

ts/oci/index.ts

@@ -3,4 +3,5 @@
  */
 
 export { OciRegistry } from './classes.ociregistry.js';
+export { OciUpstream } from './classes.ociupstream.js';
 export * from './interfaces.oci.js';

ts/plugins.ts

@@ -8,10 +8,16 @@ import * as smartarchive from '@push.rocks/smartarchive';
 import * as smartbucket from '@push.rocks/smartbucket';
 import * as smartlog from '@push.rocks/smartlog';
 import * as smartpath from '@push.rocks/smartpath';
+import * as smartrequest from '@push.rocks/smartrequest';
 
-export { smartarchive, smartbucket, smartlog, smartpath };
+export { smartarchive, smartbucket, smartlog, smartpath, smartrequest };
 
 // @tsclass scope
 import * as tsclass from '@tsclass/tsclass';
 
 export { tsclass };
+
+// third party
+import { minimatch } from 'minimatch';
+
+export { minimatch };

ts/pypi/classes.pypiregistry.ts

@@ -3,6 +3,7 @@ import { BaseRegistry } from '../core/classes.baseregistry.js';
 import { RegistryStorage } from '../core/classes.registrystorage.js';
 import { AuthManager } from '../core/classes.authmanager.js';
 import type { IRequestContext, IResponse, IAuthToken } from '../core/interfaces.core.js';
+import type { IProtocolUpstreamConfig } from '../upstream/interfaces.upstream.js';
 import { isBinaryData, toBuffer } from '../core/helpers.buffer.js';
 import type {
   IPypiPackageMetadata,
@@ -11,6 +12,7 @@ import type {
   IPypiUploadResponse,
 } from './interfaces.pypi.js';
 import * as helpers from './helpers.pypi.js';
+import { PypiUpstream } from './classes.pypiupstream.js';
 
 /**
  * PyPI registry implementation
@@ -22,12 +24,14 @@ export class PypiRegistry extends BaseRegistry {
   private basePath: string = '/pypi';
   private registryUrl: string;
   private logger: Smartlog;
+  private upstream: PypiUpstream | null = null;
 
   constructor(
     storage: RegistryStorage,
     authManager: AuthManager,
     basePath: string = '/pypi',
-    registryUrl: string = 'http://localhost:5000'
+    registryUrl: string = 'http://localhost:5000',
+    upstreamConfig?: IProtocolUpstreamConfig
   ) {
     super();
     this.storage = storage;
@@ -47,6 +51,20 @@ export class PypiRegistry extends BaseRegistry {
       }
     });
     this.logger.enableConsole();
+
+    // Initialize upstream if configured
+    if (upstreamConfig?.enabled) {
+      this.upstream = new PypiUpstream(upstreamConfig, registryUrl, this.logger);
+    }
+  }
+
+  /**
+   * Clean up resources (timers, connections, etc.)
+   */
+  public destroy(): void {
+    if (this.upstream) {
+      this.upstream.stop();
+    }
   }
 
   public async init(): Promise<void> {
@@ -214,7 +232,45 @@ export class PypiRegistry extends BaseRegistry {
     const normalized = helpers.normalizePypiPackageName(packageName);
 
     // Get package metadata
-    const metadata = await this.storage.getPypiPackageMetadata(normalized);
+    let metadata = await this.storage.getPypiPackageMetadata(normalized);
+
+    // Try upstream if not found locally
+    if (!metadata && this.upstream) {
+      const upstreamHtml = await this.upstream.fetchSimplePackage(normalized);
+      if (upstreamHtml) {
+        // Parse the HTML to extract file information and cache it
+        // For now, just return the upstream HTML directly (caching can be improved later)
+        const acceptHeader = context.headers['accept'] || context.headers['Accept'] || '';
+        const preferJson = acceptHeader.includes('application/vnd.pypi.simple') &&
+                           acceptHeader.includes('json');
+
+        if (preferJson) {
+          // Try to get JSON format from upstream
+          const upstreamJson = await this.upstream.fetchPackageJson(normalized);
+          if (upstreamJson) {
+            return {
+              status: 200,
+              headers: {
+                'Content-Type': 'application/vnd.pypi.simple.v1+json',
+                'Cache-Control': 'public, max-age=300'
+              },
+              body: upstreamJson,
+            };
+          }
+        }
+
+        // Return HTML format
+        return {
+          status: 200,
+          headers: {
+            'Content-Type': 'text/html; charset=utf-8',
+            'Cache-Control': 'public, max-age=300'
+          },
+          body: upstreamHtml,
+        };
+      }
+    }
+
     if (!metadata) {
       return this.errorResponse(404, 'Package not found');
     }
@@ -449,7 +505,16 @@ export class PypiRegistry extends BaseRegistry {
    */
   private async handleDownload(packageName: string, filename: string): Promise<IResponse> {
     const normalized = helpers.normalizePypiPackageName(packageName);
-    const fileData = await this.storage.getPypiPackageFile(normalized, filename);
+    let fileData = await this.storage.getPypiPackageFile(normalized, filename);
+
+    // Try upstream if not found locally
+    if (!fileData && this.upstream) {
+      fileData = await this.upstream.fetchPackageFile(normalized, filename);
+      if (fileData) {
+        // Cache locally
+        await this.storage.putPypiPackageFile(normalized, filename, fileData);
+      }
+    }
 
     if (!fileData) {
       return {

ts/pypi/classes.pypiupstream.ts

@@ -0,0 +1,211 @@
+import * as plugins from '../plugins.js';
+import { BaseUpstream } from '../upstream/classes.baseupstream.js';
+import type {
+  IProtocolUpstreamConfig,
+  IUpstreamFetchContext,
+  IUpstreamRegistryConfig,
+} from '../upstream/interfaces.upstream.js';
+
+/**
+ * PyPI-specific upstream implementation.
+ *
+ * Handles:
+ * - Simple API (HTML) - PEP 503
+ * - JSON API - PEP 691
+ * - Package file downloads (wheels, sdists)
+ * - Package name normalization
+ */
+export class PypiUpstream extends BaseUpstream {
+  protected readonly protocolName = 'pypi';
+
+  /** Local registry URL for rewriting download URLs */
+  private readonly localRegistryUrl: string;
+
+  constructor(
+    config: IProtocolUpstreamConfig,
+    localRegistryUrl: string,
+    logger?: plugins.smartlog.Smartlog,
+  ) {
+    super(config, logger);
+    this.localRegistryUrl = localRegistryUrl;
+  }
+
+  /**
+   * Fetch Simple API index (list of all packages) in HTML format.
+   */
+  public async fetchSimpleIndex(): Promise<string | null> {
+    const context: IUpstreamFetchContext = {
+      protocol: 'pypi',
+      resource: '*',
+      resourceType: 'index',
+      path: '/simple/',
+      method: 'GET',
+      headers: {
+        'accept': 'text/html',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    if (Buffer.isBuffer(result.body)) {
+      return result.body.toString('utf8');
+    }
+
+    return typeof result.body === 'string' ? result.body : null;
+  }
+
+  /**
+   * Fetch Simple API package page (list of files) in HTML format.
+   */
+  public async fetchSimplePackage(packageName: string): Promise<string | null> {
+    const normalizedName = this.normalizePackageName(packageName);
+    const path = `/simple/${normalizedName}/`;
+
+    const context: IUpstreamFetchContext = {
+      protocol: 'pypi',
+      resource: packageName,
+      resourceType: 'simple',
+      path,
+      method: 'GET',
+      headers: {
+        'accept': 'text/html',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    if (Buffer.isBuffer(result.body)) {
+      return result.body.toString('utf8');
+    }
+
+    return typeof result.body === 'string' ? result.body : null;
+  }
+
+  /**
+   * Fetch package metadata using JSON API (PEP 691).
+   */
+  public async fetchPackageJson(packageName: string): Promise<any | null> {
+    const normalizedName = this.normalizePackageName(packageName);
+    const path = `/simple/${normalizedName}/`;
+
+    const context: IUpstreamFetchContext = {
+      protocol: 'pypi',
+      resource: packageName,
+      resourceType: 'metadata',
+      path,
+      method: 'GET',
+      headers: {
+        'accept': 'application/vnd.pypi.simple.v1+json',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    if (Buffer.isBuffer(result.body)) {
+      return JSON.parse(result.body.toString('utf8'));
+    }
+
+    return result.body;
+  }
+
+  /**
+   * Fetch full package info from PyPI JSON API (/pypi/{package}/json).
+   */
+  public async fetchPypiJson(packageName: string): Promise<any | null> {
+    const normalizedName = this.normalizePackageName(packageName);
+    const path = `/pypi/${normalizedName}/json`;
+
+    const context: IUpstreamFetchContext = {
+      protocol: 'pypi',
+      resource: packageName,
+      resourceType: 'pypi-json',
+      path,
+      method: 'GET',
+      headers: {
+        'accept': 'application/json',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    if (Buffer.isBuffer(result.body)) {
+      return JSON.parse(result.body.toString('utf8'));
+    }
+
+    return result.body;
+  }
+
+  /**
+   * Fetch a package file (wheel or sdist) from upstream.
+   */
+  public async fetchPackageFile(packageName: string, filename: string): Promise<Buffer | null> {
+    const normalizedName = this.normalizePackageName(packageName);
+    const path = `/packages/${normalizedName}/${filename}`;
+
+    const context: IUpstreamFetchContext = {
+      protocol: 'pypi',
+      resource: packageName,
+      resourceType: 'package',
+      path,
+      method: 'GET',
+      headers: {
+        'accept': 'application/octet-stream',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    return Buffer.isBuffer(result.body) ? result.body : Buffer.from(result.body);
+  }
+
+  /**
+   * Normalize a PyPI package name according to PEP 503.
+   * - Lowercase all characters
+   * - Replace runs of ., -, _ with single -
+   */
+  private normalizePackageName(name: string): string {
+    return name.toLowerCase().replace(/[-_.]+/g, '-');
+  }
+
+  /**
+   * Override URL building for PyPI-specific handling.
+   */
+  protected buildUpstreamUrl(
+    upstream: IUpstreamRegistryConfig,
+    context: IUpstreamFetchContext,
+  ): string {
+    let baseUrl = upstream.url;
+
+    // Remove trailing slash
+    if (baseUrl.endsWith('/')) {
+      baseUrl = baseUrl.slice(0, -1);
+    }
+
+    return `${baseUrl}${context.path}`;
+  }
+}

ts/pypi/index.ts

@@ -5,4 +5,5 @@
 
 export * from './interfaces.pypi.js';
 export * from './classes.pypiregistry.js';
+export { PypiUpstream } from './classes.pypiupstream.js';
 export * as pypiHelpers from './helpers.pypi.js';

ts/rubygems/classes.rubygemsregistry.ts

@@ -3,6 +3,7 @@ import { BaseRegistry } from '../core/classes.baseregistry.js';
 import { RegistryStorage } from '../core/classes.registrystorage.js';
 import { AuthManager } from '../core/classes.authmanager.js';
 import type { IRequestContext, IResponse, IAuthToken } from '../core/interfaces.core.js';
+import type { IProtocolUpstreamConfig } from '../upstream/interfaces.upstream.js';
 import type {
   IRubyGemsMetadata,
   IRubyGemsVersionMetadata,
@@ -12,6 +13,7 @@ import type {
   ICompactIndexInfoEntry,
 } from './interfaces.rubygems.js';
 import * as helpers from './helpers.rubygems.js';
+import { RubygemsUpstream } from './classes.rubygemsupstream.js';
 
 /**
  * RubyGems registry implementation
@@ -23,12 +25,14 @@ export class RubyGemsRegistry extends BaseRegistry {
   private basePath: string = '/rubygems';
   private registryUrl: string;
   private logger: Smartlog;
+  private upstream: RubygemsUpstream | null = null;
 
   constructor(
     storage: RegistryStorage,
     authManager: AuthManager,
     basePath: string = '/rubygems',
-    registryUrl: string = 'http://localhost:5000/rubygems'
+    registryUrl: string = 'http://localhost:5000/rubygems',
+    upstreamConfig?: IProtocolUpstreamConfig
   ) {
     super();
     this.storage = storage;
@@ -48,6 +52,20 @@ export class RubyGemsRegistry extends BaseRegistry {
       }
     });
     this.logger.enableConsole();
+
+    // Initialize upstream if configured
+    if (upstreamConfig?.enabled) {
+      this.upstream = new RubygemsUpstream(upstreamConfig, this.logger);
+    }
+  }
+
+  /**
+   * Clean up resources (timers, connections, etc.)
+   */
+  public destroy(): void {
+    if (this.upstream) {
+      this.upstream.stop();
+    }
   }
 
   public async init(): Promise<void> {
@@ -215,7 +233,17 @@ export class RubyGemsRegistry extends BaseRegistry {
    * Handle /info/{gem} endpoint (Compact Index)
    */
   private async handleInfoFile(gemName: string): Promise<IResponse> {
-    const content = await this.storage.getRubyGemsInfo(gemName);
+    let content = await this.storage.getRubyGemsInfo(gemName);
+
+    // Try upstream if not found locally
+    if (!content && this.upstream) {
+      const upstreamInfo = await this.upstream.fetchInfo(gemName);
+      if (upstreamInfo) {
+        // Cache locally
+        await this.storage.putRubyGemsInfo(gemName, upstreamInfo);
+        content = upstreamInfo;
+      }
+    }
 
     if (!content) {
       return {
@@ -245,12 +273,21 @@ export class RubyGemsRegistry extends BaseRegistry {
       return this.errorResponse(400, 'Invalid gem filename');
     }
 
-    const gemData = await this.storage.getRubyGemsGem(
+    let gemData = await this.storage.getRubyGemsGem(
       parsed.name,
       parsed.version,
       parsed.platform
     );
 
+    // Try upstream if not found locally
+    if (!gemData && this.upstream) {
+      gemData = await this.upstream.fetchGem(parsed.name, parsed.version);
+      if (gemData) {
+        // Cache locally
+        await this.storage.putRubyGemsGem(parsed.name, parsed.version, gemData, parsed.platform);
+      }
+    }
+
     if (!gemData) {
       return this.errorResponse(404, 'Gem not found');
     }

ts/rubygems/classes.rubygemsupstream.ts

@@ -0,0 +1,230 @@
+import * as plugins from '../plugins.js';
+import { BaseUpstream } from '../upstream/classes.baseupstream.js';
+import type {
+  IProtocolUpstreamConfig,
+  IUpstreamFetchContext,
+  IUpstreamRegistryConfig,
+} from '../upstream/interfaces.upstream.js';
+
+/**
+ * RubyGems-specific upstream implementation.
+ *
+ * Handles:
+ * - Compact Index format (/versions, /info/{gem}, /names)
+ * - Gem file (.gem) downloading
+ * - Gem spec fetching
+ * - HTTP Range requests for incremental updates
+ */
+export class RubygemsUpstream extends BaseUpstream {
+  protected readonly protocolName = 'rubygems';
+
+  constructor(
+    config: IProtocolUpstreamConfig,
+    logger?: plugins.smartlog.Smartlog,
+  ) {
+    super(config, logger);
+  }
+
+  /**
+   * Fetch the /versions file (master list of all gems).
+   */
+  public async fetchVersions(etag?: string): Promise<{ data: string; etag?: string } | null> {
+    const headers: Record<string, string> = {
+      'accept': 'text/plain',
+    };
+
+    if (etag) {
+      headers['if-none-match'] = etag;
+    }
+
+    const context: IUpstreamFetchContext = {
+      protocol: 'rubygems',
+      resource: '*',
+      resourceType: 'versions',
+      path: '/versions',
+      method: 'GET',
+      headers,
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    let data: string;
+    if (Buffer.isBuffer(result.body)) {
+      data = result.body.toString('utf8');
+    } else if (typeof result.body === 'string') {
+      data = result.body;
+    } else {
+      return null;
+    }
+
+    return {
+      data,
+      etag: result.headers['etag'],
+    };
+  }
+
+  /**
+   * Fetch gem info file (/info/{gemname}).
+   */
+  public async fetchInfo(gemName: string): Promise<string | null> {
+    const context: IUpstreamFetchContext = {
+      protocol: 'rubygems',
+      resource: gemName,
+      resourceType: 'info',
+      path: `/info/${gemName}`,
+      method: 'GET',
+      headers: {
+        'accept': 'text/plain',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    if (Buffer.isBuffer(result.body)) {
+      return result.body.toString('utf8');
+    }
+
+    return typeof result.body === 'string' ? result.body : null;
+  }
+
+  /**
+   * Fetch the /names file (list of all gem names).
+   */
+  public async fetchNames(): Promise<string | null> {
+    const context: IUpstreamFetchContext = {
+      protocol: 'rubygems',
+      resource: '*',
+      resourceType: 'names',
+      path: '/names',
+      method: 'GET',
+      headers: {
+        'accept': 'text/plain',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    if (Buffer.isBuffer(result.body)) {
+      return result.body.toString('utf8');
+    }
+
+    return typeof result.body === 'string' ? result.body : null;
+  }
+
+  /**
+   * Fetch a gem file.
+   */
+  public async fetchGem(gemName: string, version: string): Promise<Buffer | null> {
+    const path = `/gems/${gemName}-${version}.gem`;
+
+    const context: IUpstreamFetchContext = {
+      protocol: 'rubygems',
+      resource: gemName,
+      resourceType: 'gem',
+      path,
+      method: 'GET',
+      headers: {
+        'accept': 'application/octet-stream',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    return Buffer.isBuffer(result.body) ? result.body : Buffer.from(result.body);
+  }
+
+  /**
+   * Fetch gem spec (quick spec).
+   */
+  public async fetchQuickSpec(gemName: string, version: string): Promise<Buffer | null> {
+    const path = `/quick/Marshal.4.8/${gemName}-${version}.gemspec.rz`;
+
+    const context: IUpstreamFetchContext = {
+      protocol: 'rubygems',
+      resource: gemName,
+      resourceType: 'spec',
+      path,
+      method: 'GET',
+      headers: {
+        'accept': 'application/octet-stream',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    return Buffer.isBuffer(result.body) ? result.body : Buffer.from(result.body);
+  }
+
+  /**
+   * Fetch gem versions JSON from API.
+   */
+  public async fetchVersionsJson(gemName: string): Promise<any[] | null> {
+    const path = `/api/v1/versions/${gemName}.json`;
+
+    const context: IUpstreamFetchContext = {
+      protocol: 'rubygems',
+      resource: gemName,
+      resourceType: 'versions-json',
+      path,
+      method: 'GET',
+      headers: {
+        'accept': 'application/json',
+      },
+      query: {},
+    };
+
+    const result = await this.fetch(context);
+
+    if (!result || !result.success) {
+      return null;
+    }
+
+    if (Buffer.isBuffer(result.body)) {
+      return JSON.parse(result.body.toString('utf8'));
+    }
+
+    return Array.isArray(result.body) ? result.body : null;
+  }
+
+  /**
+   * Override URL building for RubyGems-specific handling.
+   */
+  protected buildUpstreamUrl(
+    upstream: IUpstreamRegistryConfig,
+    context: IUpstreamFetchContext,
+  ): string {
+    let baseUrl = upstream.url;
+
+    // Remove trailing slash
+    if (baseUrl.endsWith('/')) {
+      baseUrl = baseUrl.slice(0, -1);
+    }
+
+    return `${baseUrl}${context.path}`;
+  }
+}

ts/rubygems/index.ts

@@ -5,4 +5,5 @@
 
 export * from './interfaces.rubygems.js';
 export * from './classes.rubygemsregistry.js';
+export { RubygemsUpstream } from './classes.rubygemsupstream.js';
 export * as rubygemsHelpers from './helpers.rubygems.js';

ts/upstream/classes.baseupstream.ts

@@ -0,0 +1,526 @@
+import * as plugins from '../plugins.js';
+import type {
+  IUpstreamRegistryConfig,
+  IUpstreamAuthConfig,
+  IUpstreamCacheConfig,
+  IUpstreamResilienceConfig,
+  IUpstreamResult,
+  IUpstreamFetchContext,
+  IProtocolUpstreamConfig,
+  IUpstreamScopeRule,
+  TCircuitState,
+} from './interfaces.upstream.js';
+import {
+  DEFAULT_CACHE_CONFIG,
+  DEFAULT_RESILIENCE_CONFIG,
+} from './interfaces.upstream.js';
+import { CircuitBreaker, CircuitOpenError, withCircuitBreaker } from './classes.circuitbreaker.js';
+import { UpstreamCache } from './classes.upstreamcache.js';
+
+/**
+ * Base class for protocol-specific upstream implementations.
+ *
+ * Provides:
+ * - Multi-upstream routing with priority
+ * - Scope-based filtering (glob patterns)
+ * - Authentication handling
+ * - Circuit breaker per upstream
+ * - Caching with TTL
+ * - Retry with exponential backoff
+ * - 429 rate limit handling
+ */
+export abstract class BaseUpstream {
+  /** Protocol name for logging */
+  protected abstract readonly protocolName: string;
+
+  /** Upstream configuration */
+  protected readonly config: IProtocolUpstreamConfig;
+
+  /** Resolved cache configuration */
+  protected readonly cacheConfig: IUpstreamCacheConfig;
+
+  /** Resolved resilience configuration */
+  protected readonly resilienceConfig: IUpstreamResilienceConfig;
+
+  /** Circuit breakers per upstream */
+  protected readonly circuitBreakers: Map<string, CircuitBreaker> = new Map();
+
+  /** Upstream cache */
+  protected readonly cache: UpstreamCache;
+
+  /** Logger instance */
+  protected readonly logger: plugins.smartlog.Smartlog;
+
+  constructor(config: IProtocolUpstreamConfig, logger?: plugins.smartlog.Smartlog) {
+    this.config = config;
+    this.cacheConfig = { ...DEFAULT_CACHE_CONFIG, ...config.cache };
+    this.resilienceConfig = { ...DEFAULT_RESILIENCE_CONFIG, ...config.resilience };
+    this.cache = new UpstreamCache(this.cacheConfig);
+    this.logger = logger || new plugins.smartlog.Smartlog({
+      logContext: {
+        company: 'smartregistry',
+        companyunit: 'upstream',
+        environment: 'production',
+        runtime: 'node',
+      }
+    });
+
+    // Initialize circuit breakers for each upstream
+    for (const upstream of config.upstreams) {
+      const upstreamResilience = { ...this.resilienceConfig, ...upstream.resilience };
+      this.circuitBreakers.set(upstream.id, new CircuitBreaker(upstream.id, upstreamResilience));
+    }
+  }
+
+  /**
+   * Check if upstream is enabled.
+   */
+  public isEnabled(): boolean {
+    return this.config.enabled;
+  }
+
+  /**
+   * Get all configured upstreams.
+   */
+  public getUpstreams(): IUpstreamRegistryConfig[] {
+    return this.config.upstreams;
+  }
+
+  /**
+   * Get circuit breaker state for an upstream.
+   */
+  public getCircuitState(upstreamId: string): TCircuitState | null {
+    const breaker = this.circuitBreakers.get(upstreamId);
+    return breaker ? breaker.getState() : null;
+  }
+
+  /**
+   * Get cache statistics.
+   */
+  public getCacheStats() {
+    return this.cache.getStats();
+  }
+
+  /**
+   * Fetch a resource from upstreams.
+   * Tries upstreams in priority order, respecting circuit breakers and scope rules.
+   */
+  public async fetch(context: IUpstreamFetchContext): Promise<IUpstreamResult | null> {
+    if (!this.config.enabled) {
+      return null;
+    }
+
+    // Get applicable upstreams sorted by priority
+    const applicableUpstreams = this.getApplicableUpstreams(context.resource);
+
+    if (applicableUpstreams.length === 0) {
+      return null;
+    }
+
+    // Use the first applicable upstream's URL for cache key
+    const primaryUpstreamUrl = applicableUpstreams[0]?.url;
+
+    // Check cache first
+    const cached = await this.cache.get(context, primaryUpstreamUrl);
+    if (cached && !cached.stale) {
+      return {
+        success: true,
+        status: 200,
+        headers: cached.headers,
+        body: cached.data,
+        upstreamId: cached.upstreamId,
+        fromCache: true,
+        latencyMs: 0,
+      };
+    }
+
+    // Check for negative cache (recent 404)
+    if (await this.cache.hasNegative(context, primaryUpstreamUrl)) {
+      return {
+        success: false,
+        status: 404,
+        headers: {},
+        upstreamId: 'cache',
+        fromCache: true,
+        latencyMs: 0,
+      };
+    }
+
+    // If we have stale cache, return it immediately and revalidate in background
+    if (cached?.stale && this.cacheConfig.staleWhileRevalidate) {
+      // Fire and forget revalidation
+      this.revalidateInBackground(context, applicableUpstreams);
+      return {
+        success: true,
+        status: 200,
+        headers: cached.headers,
+        body: cached.data,
+        upstreamId: cached.upstreamId,
+        fromCache: true,
+        latencyMs: 0,
+      };
+    }
+
+    // Try each upstream in order
+    let lastError: Error | null = null;
+
+    for (const upstream of applicableUpstreams) {
+      const breaker = this.circuitBreakers.get(upstream.id);
+      if (!breaker) continue;
+
+      try {
+        const result = await withCircuitBreaker(
+          breaker,
+          () => this.fetchFromUpstream(upstream, context),
+        );
+
+        // Cache successful responses
+        if (result.success && result.body) {
+          await this.cache.set(
+            context,
+            Buffer.isBuffer(result.body) ? result.body : Buffer.from(JSON.stringify(result.body)),
+            result.headers['content-type'] || 'application/octet-stream',
+            result.headers,
+            upstream.id,
+            upstream.url,
+          );
+        }
+
+        // Cache 404 responses
+        if (result.status === 404) {
+          await this.cache.setNegative(context, upstream.id, upstream.url);
+        }
+
+        return result;
+      } catch (error) {
+        if (error instanceof CircuitOpenError) {
+          this.logger.log('debug', `Circuit open for upstream ${upstream.id}, trying next`);
+        } else {
+          this.logger.log('warn', `Upstream ${upstream.id} failed: ${(error as Error).message}`);
+        }
+        lastError = error as Error;
+        // Continue to next upstream
+      }
+    }
+
+    // All upstreams failed
+    if (lastError) {
+      this.logger.log('error', `All upstreams failed for ${context.resource}: ${lastError.message}`);
+    }
+
+    return null;
+  }
+
+  /**
+   * Invalidate cache for a resource pattern.
+   */
+  public async invalidateCache(pattern: RegExp): Promise<number> {
+    return this.cache.invalidatePattern(pattern);
+  }
+
+  /**
+   * Clear all cache entries.
+   */
+  public async clearCache(): Promise<void> {
+    await this.cache.clear();
+  }
+
+  /**
+   * Stop the upstream (cleanup resources).
+   */
+  public stop(): void {
+    this.cache.stop();
+  }
+
+  /**
+   * Get upstreams that apply to a resource, sorted by priority.
+   */
+  protected getApplicableUpstreams(resource: string): IUpstreamRegistryConfig[] {
+    return this.config.upstreams
+      .filter(upstream => {
+        if (!upstream.enabled) return false;
+
+        // Check circuit breaker
+        const breaker = this.circuitBreakers.get(upstream.id);
+        if (breaker && !breaker.canRequest()) return false;
+
+        // Check scope rules
+        return this.matchesScopeRules(resource, upstream.scopeRules);
+      })
+      .sort((a, b) => a.priority - b.priority);
+  }
+
+  /**
+   * Check if a resource matches scope rules.
+   * Empty rules = match all.
+   */
+  protected matchesScopeRules(resource: string, rules?: IUpstreamScopeRule[]): boolean {
+    if (!rules || rules.length === 0) {
+      return true;
+    }
+
+    // Process rules in order
+    // Start with default exclude (nothing matches)
+    let matched = false;
+
+    for (const rule of rules) {
+      const isMatch = plugins.minimatch(resource, rule.pattern);
+      if (isMatch) {
+        matched = rule.action === 'include';
+      }
+    }
+
+    return matched;
+  }
+
+  /**
+   * Fetch from a specific upstream with retry logic.
+   */
+  protected async fetchFromUpstream(
+    upstream: IUpstreamRegistryConfig,
+    context: IUpstreamFetchContext,
+  ): Promise<IUpstreamResult> {
+    const upstreamResilience = { ...this.resilienceConfig, ...upstream.resilience };
+    const startTime = Date.now();
+
+    let lastError: Error | null = null;
+
+    for (let attempt = 0; attempt <= upstreamResilience.maxRetries; attempt++) {
+      try {
+        const result = await this.executeRequest(upstream, context, upstreamResilience.timeoutMs);
+        return {
+          ...result,
+          upstreamId: upstream.id,
+          fromCache: false,
+          latencyMs: Date.now() - startTime,
+        };
+      } catch (error) {
+        lastError = error as Error;
+
+        // Don't retry on 4xx errors (except 429)
+        if (this.isNonRetryableError(error)) {
+          break;
+        }
+
+        // Calculate delay with exponential backoff and jitter
+        if (attempt < upstreamResilience.maxRetries) {
+          const delay = this.calculateBackoffDelay(
+            attempt,
+            upstreamResilience.retryDelayMs,
+            upstreamResilience.retryMaxDelayMs,
+          );
+          await this.sleep(delay);
+        }
+      }
+    }
+
+    throw lastError || new Error('Request failed');
+  }
+
+  /**
+   * Execute a single HTTP request to an upstream.
+   */
+  protected async executeRequest(
+    upstream: IUpstreamRegistryConfig,
+    context: IUpstreamFetchContext,
+    timeoutMs: number,
+  ): Promise<Omit<IUpstreamResult, 'upstreamId' | 'fromCache' | 'latencyMs'>> {
+    // Build the full URL
+    const url = this.buildUpstreamUrl(upstream, context);
+
+    // Build headers with auth
+    const headers = this.buildHeaders(upstream, context);
+
+    // Make the request using SmartRequest
+    const request = plugins.smartrequest.SmartRequest.create()
+      .url(url)
+      .method(context.method as any)
+      .headers(headers)
+      .timeout(timeoutMs)
+      .handle429Backoff({ maxRetries: 3, fallbackDelay: 1000, maxWaitTime: 30000 });
+
+    // Add query params if present
+    if (Object.keys(context.query).length > 0) {
+      request.query(context.query);
+    }
+
+    let response: plugins.smartrequest.ICoreResponse;
+
+    switch (context.method.toUpperCase()) {
+      case 'GET':
+        response = await request.get();
+        break;
+      case 'HEAD':
+        // SmartRequest doesn't have head(), use options
+        response = await request.method('HEAD').get();
+        break;
+      default:
+        response = await request.get();
+    }
+
+    // Parse response
+    const responseHeaders: Record<string, string> = {};
+    for (const [key, value] of Object.entries(response.headers)) {
+      responseHeaders[key.toLowerCase()] = Array.isArray(value) ? value[0] : value;
+    }
+
+    let body: Buffer | any;
+    const contentType = responseHeaders['content-type'] || '';
+
+    if (response.ok) {
+      if (contentType.includes('application/json')) {
+        body = await response.json();
+      } else {
+        const arrayBuffer = await response.arrayBuffer();
+        body = Buffer.from(arrayBuffer);
+      }
+    }
+
+    return {
+      success: response.ok,
+      status: response.status,
+      headers: responseHeaders,
+      body,
+    };
+  }
+
+  /**
+   * Build the full URL for an upstream request.
+   * Subclasses can override for protocol-specific URL building.
+   */
+  protected buildUpstreamUrl(upstream: IUpstreamRegistryConfig, context: IUpstreamFetchContext): string {
+    // Remove leading slash if URL already has trailing slash
+    let path = context.path;
+    if (upstream.url.endsWith('/') && path.startsWith('/')) {
+      path = path.slice(1);
+    }
+    return `${upstream.url}${path}`;
+  }
+
+  /**
+   * Build headers including authentication.
+   */
+  protected buildHeaders(
+    upstream: IUpstreamRegistryConfig,
+    context: IUpstreamFetchContext,
+  ): Record<string, string> {
+    const headers: Record<string, string> = { ...context.headers };
+
+    // Remove host header (will be set by HTTP client)
+    delete headers['host'];
+
+    // Add authentication
+    this.addAuthHeaders(headers, upstream.auth);
+
+    return headers;
+  }
+
+  /**
+   * Add authentication headers based on auth config.
+   */
+  protected addAuthHeaders(headers: Record<string, string>, auth: IUpstreamAuthConfig): void {
+    switch (auth.type) {
+      case 'basic':
+        if (auth.username && auth.password) {
+          const credentials = Buffer.from(`${auth.username}:${auth.password}`).toString('base64');
+          headers['authorization'] = `Basic ${credentials}`;
+        }
+        break;
+      case 'bearer':
+        if (auth.token) {
+          headers['authorization'] = `Bearer ${auth.token}`;
+        }
+        break;
+      case 'api-key':
+        if (auth.token) {
+          const headerName = auth.headerName || 'authorization';
+          headers[headerName.toLowerCase()] = auth.token;
+        }
+        break;
+      case 'none':
+      default:
+        // No authentication
+        break;
+    }
+  }
+
+  /**
+   * Check if an error should not be retried.
+   */
+  protected isNonRetryableError(error: unknown): boolean {
+    // Check for HTTP status errors
+    if (error && typeof error === 'object' && 'status' in error) {
+      const status = (error as { status: number }).status;
+      // Don't retry 4xx errors except 429 (rate limited)
+      if (status >= 400 && status < 500 && status !== 429) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  /**
+   * Calculate backoff delay with exponential backoff and jitter.
+   */
+  protected calculateBackoffDelay(
+    attempt: number,
+    baseDelayMs: number,
+    maxDelayMs: number,
+  ): number {
+    // Exponential backoff: delay = base * 2^attempt
+    const exponentialDelay = baseDelayMs * Math.pow(2, attempt);
+
+    // Cap at max delay
+    const cappedDelay = Math.min(exponentialDelay, maxDelayMs);
+
+    // Add jitter (±25%)
+    const jitter = cappedDelay * 0.25 * (Math.random() * 2 - 1);
+
+    return Math.floor(cappedDelay + jitter);
+  }
+
+  /**
+   * Sleep for a specified duration.
+   */
+  protected sleep(ms: number): Promise<void> {
+    return new Promise(resolve => setTimeout(resolve, ms));
+  }
+
+  /**
+   * Revalidate cache in background.
+   */
+  protected async revalidateInBackground(
+    context: IUpstreamFetchContext,
+    upstreams: IUpstreamRegistryConfig[],
+  ): Promise<void> {
+    try {
+      for (const upstream of upstreams) {
+        const breaker = this.circuitBreakers.get(upstream.id);
+        if (!breaker || !breaker.canRequest()) continue;
+
+        try {
+          const result = await withCircuitBreaker(
+            breaker,
+            () => this.fetchFromUpstream(upstream, context),
+          );
+
+          if (result.success && result.body) {
+            await this.cache.set(
+              context,
+              Buffer.isBuffer(result.body) ? result.body : Buffer.from(JSON.stringify(result.body)),
+              result.headers['content-type'] || 'application/octet-stream',
+              result.headers,
+              upstream.id,
+              upstream.url,
+            );
+            return; // Successfully revalidated
+          }
+        } catch {
+          // Continue to next upstream
+        }
+      }
+    } catch (error) {
+      this.logger.log('debug', `Background revalidation failed: ${(error as Error).message}`);
+    }
+  }
+}

ts/upstream/classes.circuitbreaker.ts

@@ -0,0 +1,238 @@
+import type { TCircuitState, IUpstreamResilienceConfig } from './interfaces.upstream.js';
+import { DEFAULT_RESILIENCE_CONFIG } from './interfaces.upstream.js';
+
+/**
+ * Circuit breaker implementation for upstream resilience.
+ *
+ * States:
+ * - CLOSED: Normal operation, requests pass through
+ * - OPEN: Circuit is tripped, requests fail fast
+ * - HALF_OPEN: Testing if upstream has recovered
+ *
+ * Transitions:
+ * - CLOSED → OPEN: When failure count exceeds threshold
+ * - OPEN → HALF_OPEN: After reset timeout expires
+ * - HALF_OPEN → CLOSED: On successful request
+ * - HALF_OPEN → OPEN: On failed request
+ */
+export class CircuitBreaker {
+  /** Unique identifier for logging and metrics */
+  public readonly id: string;
+
+  /** Current circuit state */
+  private state: TCircuitState = 'CLOSED';
+
+  /** Count of consecutive failures */
+  private failureCount: number = 0;
+
+  /** Timestamp when circuit was opened */
+  private openedAt: number = 0;
+
+  /** Number of successful requests in half-open state */
+  private halfOpenSuccesses: number = 0;
+
+  /** Configuration */
+  private readonly config: IUpstreamResilienceConfig;
+
+  /** Number of successes required to close circuit from half-open */
+  private readonly halfOpenThreshold: number = 2;
+
+  constructor(id: string, config?: Partial<IUpstreamResilienceConfig>) {
+    this.id = id;
+    this.config = { ...DEFAULT_RESILIENCE_CONFIG, ...config };
+  }
+
+  /**
+   * Get current circuit state.
+   */
+  public getState(): TCircuitState {
+    // Check if we should transition from OPEN to HALF_OPEN
+    if (this.state === 'OPEN') {
+      const elapsed = Date.now() - this.openedAt;
+      if (elapsed >= this.config.circuitBreakerResetMs) {
+        this.transitionTo('HALF_OPEN');
+      }
+    }
+    return this.state;
+  }
+
+  /**
+   * Check if circuit allows requests.
+   * Returns true if requests should be allowed.
+   */
+  public canRequest(): boolean {
+    const currentState = this.getState();
+    return currentState !== 'OPEN';
+  }
+
+  /**
+   * Record a successful request.
+   * May transition circuit from HALF_OPEN to CLOSED.
+   */
+  public recordSuccess(): void {
+    if (this.state === 'HALF_OPEN') {
+      this.halfOpenSuccesses++;
+      if (this.halfOpenSuccesses >= this.halfOpenThreshold) {
+        this.transitionTo('CLOSED');
+      }
+    } else if (this.state === 'CLOSED') {
+      // Reset failure count on success
+      this.failureCount = 0;
+    }
+  }
+
+  /**
+   * Record a failed request.
+   * May transition circuit from CLOSED/HALF_OPEN to OPEN.
+   */
+  public recordFailure(): void {
+    if (this.state === 'HALF_OPEN') {
+      // Any failure in half-open immediately opens circuit
+      this.transitionTo('OPEN');
+    } else if (this.state === 'CLOSED') {
+      this.failureCount++;
+      if (this.failureCount >= this.config.circuitBreakerThreshold) {
+        this.transitionTo('OPEN');
+      }
+    }
+  }
+
+  /**
+   * Force circuit to open state.
+   * Useful for manual intervention or external health checks.
+   */
+  public forceOpen(): void {
+    this.transitionTo('OPEN');
+  }
+
+  /**
+   * Force circuit to closed state.
+   * Useful for manual intervention after fixing upstream issues.
+   */
+  public forceClose(): void {
+    this.transitionTo('CLOSED');
+  }
+
+  /**
+   * Reset circuit to initial state.
+   */
+  public reset(): void {
+    this.state = 'CLOSED';
+    this.failureCount = 0;
+    this.openedAt = 0;
+    this.halfOpenSuccesses = 0;
+  }
+
+  /**
+   * Get circuit metrics for monitoring.
+   */
+  public getMetrics(): ICircuitBreakerMetrics {
+    return {
+      id: this.id,
+      state: this.getState(),
+      failureCount: this.failureCount,
+      openedAt: this.openedAt > 0 ? new Date(this.openedAt) : null,
+      timeUntilHalfOpen: this.state === 'OPEN'
+        ? Math.max(0, this.config.circuitBreakerResetMs - (Date.now() - this.openedAt))
+        : 0,
+      halfOpenSuccesses: this.halfOpenSuccesses,
+      threshold: this.config.circuitBreakerThreshold,
+      resetMs: this.config.circuitBreakerResetMs,
+    };
+  }
+
+  /**
+   * Transition to a new state with proper cleanup.
+   */
+  private transitionTo(newState: TCircuitState): void {
+    const previousState = this.state;
+    this.state = newState;
+
+    switch (newState) {
+      case 'OPEN':
+        this.openedAt = Date.now();
+        this.halfOpenSuccesses = 0;
+        break;
+      case 'HALF_OPEN':
+        this.halfOpenSuccesses = 0;
+        break;
+      case 'CLOSED':
+        this.failureCount = 0;
+        this.openedAt = 0;
+        this.halfOpenSuccesses = 0;
+        break;
+    }
+
+    // Log state transition (useful for debugging and monitoring)
+    // In production, this would emit events or metrics
+    if (previousState !== newState) {
+      // State changed - could emit event here
+    }
+  }
+}
+
+/**
+ * Metrics for circuit breaker monitoring.
+ */
+export interface ICircuitBreakerMetrics {
+  /** Circuit breaker identifier */
+  id: string;
+  /** Current state */
+  state: TCircuitState;
+  /** Number of consecutive failures */
+  failureCount: number;
+  /** When circuit was opened (null if never opened) */
+  openedAt: Date | null;
+  /** Milliseconds until circuit transitions to half-open (0 if not open) */
+  timeUntilHalfOpen: number;
+  /** Number of successes in half-open state */
+  halfOpenSuccesses: number;
+  /** Failure threshold for opening circuit */
+  threshold: number;
+  /** Reset timeout in milliseconds */
+  resetMs: number;
+}
+
+/**
+ * Execute a function with circuit breaker protection.
+ *
+ * @param breaker The circuit breaker to use
+ * @param fn The async function to execute
+ * @param fallback Optional fallback function when circuit is open
+ * @returns The result of fn or fallback
+ * @throws CircuitOpenError if circuit is open and no fallback provided
+ */
+export async function withCircuitBreaker<T>(
+  breaker: CircuitBreaker,
+  fn: () => Promise<T>,
+  fallback?: () => Promise<T>,
+): Promise<T> {
+  if (!breaker.canRequest()) {
+    if (fallback) {
+      return fallback();
+    }
+    throw new CircuitOpenError(breaker.id);
+  }
+
+  try {
+    const result = await fn();
+    breaker.recordSuccess();
+    return result;
+  } catch (error) {
+    breaker.recordFailure();
+    throw error;
+  }
+}
+
+/**
+ * Error thrown when circuit is open and no fallback is provided.
+ */
+export class CircuitOpenError extends Error {
+  public readonly circuitId: string;
+
+  constructor(circuitId: string) {
+    super(`Circuit breaker '${circuitId}' is open`);
+    this.name = 'CircuitOpenError';
+    this.circuitId = circuitId;
+  }
+}

ts/upstream/classes.upstreamcache.ts

@@ -0,0 +1,626 @@
+import type {
+  ICacheEntry,
+  IUpstreamCacheConfig,
+  IUpstreamFetchContext,
+} from './interfaces.upstream.js';
+import { DEFAULT_CACHE_CONFIG } from './interfaces.upstream.js';
+import type { IStorageBackend } from '../core/interfaces.core.js';
+
+/**
+ * Cache metadata stored alongside cache entries.
+ */
+interface ICacheMetadata {
+  contentType: string;
+  headers: Record<string, string>;
+  cachedAt: string;
+  expiresAt?: string;
+  etag?: string;
+  upstreamId: string;
+  upstreamUrl: string;
+}
+
+/**
+ * S3-backed upstream cache with in-memory hot layer.
+ *
+ * Features:
+ * - TTL-based expiration
+ * - Stale-while-revalidate support
+ * - Negative caching (404s)
+ * - Content-type aware caching
+ * - ETag support for conditional requests
+ * - Multi-upstream support via URL-based cache paths
+ * - Persistent S3 storage with in-memory hot layer
+ *
+ * Cache paths are structured as:
+ *   cache/{escaped-upstream-url}/{protocol}:{method}:{path}
+ *
+ * @example
+ * ```typescript
+ * // In-memory only (default)
+ * const cache = new UpstreamCache(config);
+ *
+ * // With S3 persistence
+ * const cache = new UpstreamCache(config, 10000, storage);
+ * ```
+ */
+export class UpstreamCache {
+  /** In-memory hot cache */
+  private readonly memoryCache: Map<string, ICacheEntry> = new Map();
+
+  /** Configuration */
+  private readonly config: IUpstreamCacheConfig;
+
+  /** Maximum in-memory cache entries */
+  private readonly maxMemoryEntries: number;
+
+  /** S3 storage backend (optional) */
+  private readonly storage?: IStorageBackend;
+
+  /** Cleanup interval handle */
+  private cleanupInterval: ReturnType<typeof setInterval> | null = null;
+
+  constructor(
+    config?: Partial<IUpstreamCacheConfig>,
+    maxMemoryEntries: number = 10000,
+    storage?: IStorageBackend
+  ) {
+    this.config = { ...DEFAULT_CACHE_CONFIG, ...config };
+    this.maxMemoryEntries = maxMemoryEntries;
+    this.storage = storage;
+
+    // Start periodic cleanup if caching is enabled
+    if (this.config.enabled) {
+      this.startCleanup();
+    }
+  }
+
+  /**
+   * Check if caching is enabled.
+   */
+  public isEnabled(): boolean {
+    return this.config.enabled;
+  }
+
+  /**
+   * Check if S3 storage is configured.
+   */
+  public hasStorage(): boolean {
+    return !!this.storage;
+  }
+
+  /**
+   * Get cached entry for a request context.
+   * Checks memory first, then falls back to S3.
+   * Returns null if not found or expired (unless stale-while-revalidate).
+   */
+  public async get(context: IUpstreamFetchContext, upstreamUrl?: string): Promise<ICacheEntry | null> {
+    if (!this.config.enabled) {
+      return null;
+    }
+
+    const key = this.buildCacheKey(context, upstreamUrl);
+
+    // Check memory cache first
+    let entry = this.memoryCache.get(key);
+
+    // If not in memory and we have storage, check S3
+    if (!entry && this.storage) {
+      entry = await this.loadFromStorage(key);
+      if (entry) {
+        // Promote to memory cache
+        this.memoryCache.set(key, entry);
+      }
+    }
+
+    if (!entry) {
+      return null;
+    }
+
+    const now = new Date();
+
+    // Check if entry is expired
+    if (entry.expiresAt && entry.expiresAt < now) {
+      // Check if we can serve stale content
+      if (this.config.staleWhileRevalidate && !entry.stale) {
+        const staleAge = (now.getTime() - entry.expiresAt.getTime()) / 1000;
+        if (staleAge <= this.config.staleMaxAgeSeconds) {
+          // Mark as stale and return
+          entry.stale = true;
+          return entry;
+        }
+      }
+      // Entry is too old, remove it
+      this.memoryCache.delete(key);
+      if (this.storage) {
+        await this.deleteFromStorage(key).catch(() => {});
+      }
+      return null;
+    }
+
+    return entry;
+  }
+
+  /**
+   * Store a response in the cache (memory and optionally S3).
+   */
+  public async set(
+    context: IUpstreamFetchContext,
+    data: Buffer,
+    contentType: string,
+    headers: Record<string, string>,
+    upstreamId: string,
+    upstreamUrl: string,
+    options?: ICacheSetOptions,
+  ): Promise<void> {
+    if (!this.config.enabled) {
+      return;
+    }
+
+    // Enforce max memory entries limit
+    if (this.memoryCache.size >= this.maxMemoryEntries) {
+      this.evictOldest();
+    }
+
+    const key = this.buildCacheKey(context, upstreamUrl);
+    const now = new Date();
+
+    // Determine TTL based on content type
+    const ttlSeconds = options?.ttlSeconds ?? this.determineTtl(context, contentType, headers);
+
+    const entry: ICacheEntry = {
+      data,
+      contentType,
+      headers,
+      cachedAt: now,
+      expiresAt: ttlSeconds > 0 ? new Date(now.getTime() + ttlSeconds * 1000) : undefined,
+      etag: headers['etag'] || options?.etag,
+      upstreamId,
+      stale: false,
+    };
+
+    // Store in memory
+    this.memoryCache.set(key, entry);
+
+    // Store in S3 if available
+    if (this.storage) {
+      await this.saveToStorage(key, entry, upstreamUrl).catch(() => {});
+    }
+  }
+
+  /**
+   * Store a negative cache entry (404 response).
+   */
+  public async setNegative(context: IUpstreamFetchContext, upstreamId: string, upstreamUrl: string): Promise<void> {
+    if (!this.config.enabled || this.config.negativeCacheTtlSeconds <= 0) {
+      return;
+    }
+
+    const key = this.buildCacheKey(context, upstreamUrl);
+    const now = new Date();
+
+    const entry: ICacheEntry = {
+      data: Buffer.from(''),
+      contentType: 'application/octet-stream',
+      headers: {},
+      cachedAt: now,
+      expiresAt: new Date(now.getTime() + this.config.negativeCacheTtlSeconds * 1000),
+      upstreamId,
+      stale: false,
+    };
+
+    this.memoryCache.set(key, entry);
+
+    if (this.storage) {
+      await this.saveToStorage(key, entry, upstreamUrl).catch(() => {});
+    }
+  }
+
+  /**
+   * Check if there's a negative cache entry for this context.
+   */
+  public async hasNegative(context: IUpstreamFetchContext, upstreamUrl?: string): Promise<boolean> {
+    const entry = await this.get(context, upstreamUrl);
+    return entry !== null && entry.data.length === 0;
+  }
+
+  /**
+   * Invalidate a specific cache entry.
+   */
+  public async invalidate(context: IUpstreamFetchContext, upstreamUrl?: string): Promise<boolean> {
+    const key = this.buildCacheKey(context, upstreamUrl);
+    const deleted = this.memoryCache.delete(key);
+
+    if (this.storage) {
+      await this.deleteFromStorage(key).catch(() => {});
+    }
+
+    return deleted;
+  }
+
+  /**
+   * Invalidate all entries matching a pattern.
+   * Useful for invalidating all versions of a package.
+   */
+  public async invalidatePattern(pattern: RegExp): Promise<number> {
+    let count = 0;
+    for (const key of this.memoryCache.keys()) {
+      if (pattern.test(key)) {
+        this.memoryCache.delete(key);
+        if (this.storage) {
+          await this.deleteFromStorage(key).catch(() => {});
+        }
+        count++;
+      }
+    }
+    return count;
+  }
+
+  /**
+   * Invalidate all entries from a specific upstream.
+   */
+  public async invalidateUpstream(upstreamId: string): Promise<number> {
+    let count = 0;
+    for (const [key, entry] of this.memoryCache.entries()) {
+      if (entry.upstreamId === upstreamId) {
+        this.memoryCache.delete(key);
+        if (this.storage) {
+          await this.deleteFromStorage(key).catch(() => {});
+        }
+        count++;
+      }
+    }
+    return count;
+  }
+
+  /**
+   * Clear all cache entries (memory and S3).
+   */
+  public async clear(): Promise<void> {
+    this.memoryCache.clear();
+
+    // Note: S3 cleanup would require listing and deleting all cache/* objects
+    // This is left as a future enhancement for bulk cleanup
+  }
+
+  /**
+   * Get cache statistics.
+   */
+  public getStats(): ICacheStats {
+    let freshCount = 0;
+    let staleCount = 0;
+    let negativeCount = 0;
+    let totalSize = 0;
+    const now = new Date();
+
+    for (const entry of this.memoryCache.values()) {
+      totalSize += entry.data.length;
+
+      if (entry.data.length === 0) {
+        negativeCount++;
+      } else if (entry.stale || (entry.expiresAt && entry.expiresAt < now)) {
+        staleCount++;
+      } else {
+        freshCount++;
+      }
+    }
+
+    return {
+      totalEntries: this.memoryCache.size,
+      freshEntries: freshCount,
+      staleEntries: staleCount,
+      negativeEntries: negativeCount,
+      totalSizeBytes: totalSize,
+      maxEntries: this.maxMemoryEntries,
+      enabled: this.config.enabled,
+      hasStorage: !!this.storage,
+    };
+  }
+
+  /**
+   * Stop the cache and cleanup.
+   */
+  public stop(): void {
+    if (this.cleanupInterval) {
+      clearInterval(this.cleanupInterval);
+      this.cleanupInterval = null;
+    }
+  }
+
+  // ========================================================================
+  // Storage Methods
+  // ========================================================================
+
+  /**
+   * Build storage path for a cache key.
+   * Escapes upstream URL for safe use in S3 paths.
+   */
+  private buildStoragePath(key: string): string {
+    return `cache/${key}`;
+  }
+
+  /**
+   * Build storage path for cache metadata.
+   */
+  private buildMetadataPath(key: string): string {
+    return `cache/${key}.meta`;
+  }
+
+  /**
+   * Load a cache entry from S3 storage.
+   */
+  private async loadFromStorage(key: string): Promise<ICacheEntry | null> {
+    if (!this.storage) return null;
+
+    try {
+      const dataPath = this.buildStoragePath(key);
+      const metaPath = this.buildMetadataPath(key);
+
+      // Load data and metadata in parallel
+      const [data, metaBuffer] = await Promise.all([
+        this.storage.getObject(dataPath),
+        this.storage.getObject(metaPath),
+      ]);
+
+      if (!data || !metaBuffer) {
+        return null;
+      }
+
+      const meta: ICacheMetadata = JSON.parse(metaBuffer.toString('utf-8'));
+
+      return {
+        data,
+        contentType: meta.contentType,
+        headers: meta.headers,
+        cachedAt: new Date(meta.cachedAt),
+        expiresAt: meta.expiresAt ? new Date(meta.expiresAt) : undefined,
+        etag: meta.etag,
+        upstreamId: meta.upstreamId,
+        stale: false,
+      };
+    } catch {
+      return null;
+    }
+  }
+
+  /**
+   * Save a cache entry to S3 storage.
+   */
+  private async saveToStorage(key: string, entry: ICacheEntry, upstreamUrl: string): Promise<void> {
+    if (!this.storage) return;
+
+    const dataPath = this.buildStoragePath(key);
+    const metaPath = this.buildMetadataPath(key);
+
+    const meta: ICacheMetadata = {
+      contentType: entry.contentType,
+      headers: entry.headers,
+      cachedAt: entry.cachedAt.toISOString(),
+      expiresAt: entry.expiresAt?.toISOString(),
+      etag: entry.etag,
+      upstreamId: entry.upstreamId,
+      upstreamUrl,
+    };
+
+    // Save data and metadata in parallel
+    await Promise.all([
+      this.storage.putObject(dataPath, entry.data),
+      this.storage.putObject(metaPath, Buffer.from(JSON.stringify(meta), 'utf-8')),
+    ]);
+  }
+
+  /**
+   * Delete a cache entry from S3 storage.
+   */
+  private async deleteFromStorage(key: string): Promise<void> {
+    if (!this.storage) return;
+
+    const dataPath = this.buildStoragePath(key);
+    const metaPath = this.buildMetadataPath(key);
+
+    await Promise.all([
+      this.storage.deleteObject(dataPath).catch(() => {}),
+      this.storage.deleteObject(metaPath).catch(() => {}),
+    ]);
+  }
+
+  // ========================================================================
+  // Helper Methods
+  // ========================================================================
+
+  /**
+   * Escape a URL for safe use in storage paths.
+   */
+  private escapeUrl(url: string): string {
+    // Remove protocol prefix and escape special characters
+    return url
+      .replace(/^https?:\/\//, '')
+      .replace(/[\/\\:*?"<>|]/g, '_')
+      .replace(/__+/g, '_');
+  }
+
+  /**
+   * Build a unique cache key for a request context.
+   * Includes escaped upstream URL for multi-upstream support.
+   */
+  private buildCacheKey(context: IUpstreamFetchContext, upstreamUrl?: string): string {
+    // Include method, protocol, path, and sorted query params
+    const queryString = Object.keys(context.query)
+      .sort()
+      .map(k => `${k}=${context.query[k]}`)
+      .join('&');
+
+    const baseKey = `${context.protocol}:${context.method}:${context.path}${queryString ? '?' + queryString : ''}`;
+
+    if (upstreamUrl) {
+      return `${this.escapeUrl(upstreamUrl)}/${baseKey}`;
+    }
+
+    return baseKey;
+  }
+
+  /**
+   * Determine TTL based on content characteristics.
+   */
+  private determineTtl(
+    context: IUpstreamFetchContext,
+    contentType: string,
+    headers: Record<string, string>,
+  ): number {
+    // Check for Cache-Control header
+    const cacheControl = headers['cache-control'];
+    if (cacheControl) {
+      const maxAgeMatch = cacheControl.match(/max-age=(\d+)/);
+      if (maxAgeMatch) {
+        return parseInt(maxAgeMatch[1], 10);
+      }
+      if (cacheControl.includes('no-store') || cacheControl.includes('no-cache')) {
+        return 0;
+      }
+    }
+
+    // Check if content is immutable (content-addressable)
+    if (this.isImmutableContent(context, contentType)) {
+      return this.config.immutableTtlSeconds;
+    }
+
+    // Default TTL for mutable content
+    return this.config.defaultTtlSeconds;
+  }
+
+  /**
+   * Check if content is immutable (content-addressable).
+   */
+  private isImmutableContent(context: IUpstreamFetchContext, contentType: string): boolean {
+    // OCI blobs with digest are immutable
+    if (context.protocol === 'oci' && context.resourceType === 'blob') {
+      return true;
+    }
+
+    // NPM tarballs are immutable (versioned)
+    if (context.protocol === 'npm' && context.resourceType === 'tarball') {
+      return true;
+    }
+
+    // Maven artifacts with version are immutable
+    if (context.protocol === 'maven' && context.resourceType === 'artifact') {
+      return true;
+    }
+
+    // Cargo crate files are immutable
+    if (context.protocol === 'cargo' && context.resourceType === 'crate') {
+      return true;
+    }
+
+    // Composer dist files are immutable
+    if (context.protocol === 'composer' && context.resourceType === 'dist') {
+      return true;
+    }
+
+    // PyPI package files are immutable
+    if (context.protocol === 'pypi' && context.resourceType === 'package') {
+      return true;
+    }
+
+    // RubyGems .gem files are immutable
+    if (context.protocol === 'rubygems' && context.resourceType === 'gem') {
+      return true;
+    }
+
+    return false;
+  }
+
+  /**
+   * Evict oldest entries to make room for new ones.
+   */
+  private evictOldest(): void {
+    // Evict 10% of max entries
+    const evictCount = Math.ceil(this.maxMemoryEntries * 0.1);
+    let evicted = 0;
+
+    // First, try to evict stale entries
+    const now = new Date();
+    for (const [key, entry] of this.memoryCache.entries()) {
+      if (evicted >= evictCount) break;
+      if (entry.stale || (entry.expiresAt && entry.expiresAt < now)) {
+        this.memoryCache.delete(key);
+        evicted++;
+      }
+    }
+
+    // If not enough evicted, evict oldest by cachedAt
+    if (evicted < evictCount) {
+      const entries = Array.from(this.memoryCache.entries())
+        .sort((a, b) => a[1].cachedAt.getTime() - b[1].cachedAt.getTime());
+
+      for (const [key] of entries) {
+        if (evicted >= evictCount) break;
+        this.memoryCache.delete(key);
+        evicted++;
+      }
+    }
+  }
+
+  /**
+   * Start periodic cleanup of expired entries.
+   */
+  private startCleanup(): void {
+    // Run cleanup every minute
+    this.cleanupInterval = setInterval(() => {
+      this.cleanup();
+    }, 60000);
+
+    // Don't keep the process alive just for cleanup
+    if (this.cleanupInterval.unref) {
+      this.cleanupInterval.unref();
+    }
+  }
+
+  /**
+   * Remove all expired entries from memory cache.
+   */
+  private cleanup(): void {
+    const now = new Date();
+    const staleDeadline = new Date(now.getTime() - this.config.staleMaxAgeSeconds * 1000);
+
+    for (const [key, entry] of this.memoryCache.entries()) {
+      if (entry.expiresAt) {
+        // Remove if past stale deadline
+        if (entry.expiresAt < staleDeadline) {
+          this.memoryCache.delete(key);
+        }
+      }
+    }
+  }
+}
+
+/**
+ * Options for cache set operation.
+ */
+export interface ICacheSetOptions {
+  /** Override TTL in seconds */
+  ttlSeconds?: number;
+  /** ETag for conditional requests */
+  etag?: string;
+}
+
+/**
+ * Cache statistics.
+ */
+export interface ICacheStats {
+  /** Total number of cached entries in memory */
+  totalEntries: number;
+  /** Number of fresh (non-expired) entries */
+  freshEntries: number;
+  /** Number of stale entries (expired but still usable) */
+  staleEntries: number;
+  /** Number of negative cache entries */
+  negativeEntries: number;
+  /** Total size of cached data in bytes (memory only) */
+  totalSizeBytes: number;
+  /** Maximum allowed memory entries */
+  maxEntries: number;
+  /** Whether caching is enabled */
+  enabled: boolean;
+  /** Whether S3 storage is configured */
+  hasStorage: boolean;
+}

ts/upstream/index.ts

@@ -0,0 +1,11 @@
+// Interfaces and types
+export * from './interfaces.upstream.js';
+
+// Classes
+export { CircuitBreaker, CircuitOpenError, withCircuitBreaker } from './classes.circuitbreaker.js';
+export type { ICircuitBreakerMetrics } from './classes.circuitbreaker.js';
+
+export { UpstreamCache } from './classes.upstreamcache.js';
+export type { ICacheSetOptions, ICacheStats } from './classes.upstreamcache.js';
+
+export { BaseUpstream } from './classes.baseupstream.js';

ts/upstream/interfaces.upstream.ts

@@ -0,0 +1,195 @@
+import type { TRegistryProtocol } from '../core/interfaces.core.js';
+
+/**
+ * Scope rule for routing requests to specific upstreams.
+ * Uses glob patterns for flexible matching.
+ */
+export interface IUpstreamScopeRule {
+  /** Glob pattern (e.g., "@company/*", "com.example.*", "library/*") */
+  pattern: string;
+  /** Whether matching resources should be included or excluded */
+  action: 'include' | 'exclude';
+}
+
+/**
+ * Authentication configuration for an upstream registry.
+ * Supports multiple auth strategies.
+ */
+export interface IUpstreamAuthConfig {
+  /** Authentication type */
+  type: 'none' | 'basic' | 'bearer' | 'api-key';
+  /** Username for basic auth */
+  username?: string;
+  /** Password for basic auth */
+  password?: string;
+  /** Token for bearer or api-key auth */
+  token?: string;
+  /** Custom header name for api-key auth (default: 'Authorization') */
+  headerName?: string;
+}
+
+/**
+ * Cache configuration for upstream content.
+ */
+export interface IUpstreamCacheConfig {
+  /** Whether caching is enabled */
+  enabled: boolean;
+  /** Default TTL in seconds for mutable content (default: 300 = 5 min) */
+  defaultTtlSeconds: number;
+  /** TTL in seconds for immutable/content-addressable content (default: 2592000 = 30 days) */
+  immutableTtlSeconds: number;
+  /** Whether to serve stale content while revalidating in background */
+  staleWhileRevalidate: boolean;
+  /** Maximum age in seconds for stale content (default: 3600 = 1 hour) */
+  staleMaxAgeSeconds: number;
+  /** TTL in seconds for negative cache entries (404s) (default: 60 = 1 min) */
+  negativeCacheTtlSeconds: number;
+}
+
+/**
+ * Resilience configuration for upstream requests.
+ */
+export interface IUpstreamResilienceConfig {
+  /** Request timeout in milliseconds (default: 30000) */
+  timeoutMs: number;
+  /** Maximum number of retry attempts (default: 3) */
+  maxRetries: number;
+  /** Initial retry delay in milliseconds (default: 1000) */
+  retryDelayMs: number;
+  /** Maximum retry delay in milliseconds (default: 30000) */
+  retryMaxDelayMs: number;
+  /** Number of failures before circuit breaker opens (default: 5) */
+  circuitBreakerThreshold: number;
+  /** Time in milliseconds before circuit breaker attempts reset (default: 30000) */
+  circuitBreakerResetMs: number;
+}
+
+/**
+ * Configuration for a single upstream registry.
+ */
+export interface IUpstreamRegistryConfig {
+  /** Unique identifier for this upstream */
+  id: string;
+  /** Human-readable name */
+  name: string;
+  /** Base URL of the upstream registry (e.g., "https://registry.npmjs.org") */
+  url: string;
+  /** Priority for routing (lower = higher priority, 1 = first) */
+  priority: number;
+  /** Whether this upstream is enabled */
+  enabled: boolean;
+  /** Scope rules for routing (empty = match all) */
+  scopeRules?: IUpstreamScopeRule[];
+  /** Authentication configuration */
+  auth: IUpstreamAuthConfig;
+  /** Cache configuration overrides */
+  cache?: Partial<IUpstreamCacheConfig>;
+  /** Resilience configuration overrides */
+  resilience?: Partial<IUpstreamResilienceConfig>;
+}
+
+/**
+ * Protocol-level upstream configuration.
+ * Configures upstream behavior for a specific protocol (npm, oci, etc.)
+ */
+export interface IProtocolUpstreamConfig {
+  /** Whether upstream is enabled for this protocol */
+  enabled: boolean;
+  /** List of upstream registries, ordered by priority */
+  upstreams: IUpstreamRegistryConfig[];
+  /** Protocol-level cache configuration defaults */
+  cache?: Partial<IUpstreamCacheConfig>;
+  /** Protocol-level resilience configuration defaults */
+  resilience?: Partial<IUpstreamResilienceConfig>;
+}
+
+/**
+ * Result of an upstream fetch operation.
+ */
+export interface IUpstreamResult {
+  /** Whether the fetch was successful (2xx status) */
+  success: boolean;
+  /** HTTP status code */
+  status: number;
+  /** Response headers */
+  headers: Record<string, string>;
+  /** Response body (Buffer for binary, object for JSON) */
+  body?: Buffer | any;
+  /** ID of the upstream that served the request */
+  upstreamId: string;
+  /** Whether the response was served from cache */
+  fromCache: boolean;
+  /** Request latency in milliseconds */
+  latencyMs: number;
+}
+
+/**
+ * Circuit breaker state.
+ */
+export type TCircuitState = 'CLOSED' | 'OPEN' | 'HALF_OPEN';
+
+/**
+ * Context for an upstream fetch request.
+ */
+export interface IUpstreamFetchContext {
+  /** Protocol type */
+  protocol: TRegistryProtocol;
+  /** Resource identifier (package name, artifact name, etc.) */
+  resource: string;
+  /** Type of resource being fetched (packument, tarball, manifest, blob, etc.) */
+  resourceType: string;
+  /** Original request path */
+  path: string;
+  /** HTTP method */
+  method: string;
+  /** Request headers */
+  headers: Record<string, string>;
+  /** Query parameters */
+  query: Record<string, string>;
+}
+
+/**
+ * Cache entry stored in the upstream cache.
+ */
+export interface ICacheEntry {
+  /** Cached data */
+  data: Buffer;
+  /** Content type of the cached data */
+  contentType: string;
+  /** Original response headers */
+  headers: Record<string, string>;
+  /** When the entry was cached */
+  cachedAt: Date;
+  /** When the entry expires */
+  expiresAt?: Date;
+  /** ETag for conditional requests */
+  etag?: string;
+  /** ID of the upstream that provided the data */
+  upstreamId: string;
+  /** Whether the entry is stale but still usable */
+  stale?: boolean;
+}
+
+/**
+ * Default cache configuration values.
+ */
+export const DEFAULT_CACHE_CONFIG: IUpstreamCacheConfig = {
+  enabled: true,
+  defaultTtlSeconds: 300,           // 5 minutes
+  immutableTtlSeconds: 2592000,     // 30 days
+  staleWhileRevalidate: true,
+  staleMaxAgeSeconds: 3600,         // 1 hour
+  negativeCacheTtlSeconds: 60,      // 1 minute
+};
+
+/**
+ * Default resilience configuration values.
+ */
+export const DEFAULT_RESILIENCE_CONFIG: IUpstreamResilienceConfig = {
+  timeoutMs: 30000,
+  maxRetries: 3,
+  retryDelayMs: 1000,
+  retryMaxDelayMs: 30000,
+  circuitBreakerThreshold: 5,
+  circuitBreakerResetMs: 30000,
+};