feat(cli): add global remote builder configuration and native SSH buildx nodes for multi-platform builds

changelog.md

@@ -1,5 +1,13 @@
 # Changelog
 
+## 2026-03-15 - 2.1.0 - feat(cli)
+add global remote builder configuration and native SSH buildx nodes for multi-platform builds
+
+- adds a new `tsdocker config` command with subcommands to add, remove, list, and show remote builder definitions
+- introduces global config support for remote builders stored under `~/.git.zone/tsdocker/config.json`
+- builds can now create multi-node buildx setups with remote SSH builders and open reverse SSH tunnels so remote nodes can push to the local staging registry
+- updates the README and CLI help to document remote builder configuration and native cross-platform build workflows
+
 ## 2026-03-12 - 2.0.2 - fix(repo)
 no changes to commit
 

package.json

@@ -27,22 +27,22 @@
   },
   "homepage": "https://gitlab.com/gitzone/tsdocker#readme",
   "devDependencies": {
-    "@git.zone/tsbuild": "^4.1.2",
+    "@git.zone/tsbuild": "^4.3.0",
     "@git.zone/tsrun": "^2.0.1",
-    "@git.zone/tstest": "^3.1.6",
+    "@git.zone/tstest": "^3.3.2",
-    "@types/node": "^25.0.9"
+    "@types/node": "^25.5.0"
   },
   "dependencies": {
-    "@push.rocks/lik": "^6.2.2",
+    "@push.rocks/lik": "^6.3.1",
     "@push.rocks/npmextra": "^5.3.3",
     "@push.rocks/projectinfo": "^5.0.2",
     "@push.rocks/smartcli": "^4.0.20",
-    "@push.rocks/smartfs": "^1.3.1",
+    "@push.rocks/smartfs": "^1.5.0",
     "@push.rocks/smartinteract": "^2.0.16",
-    "@push.rocks/smartlog": "^3.1.10",
+    "@push.rocks/smartlog": "^3.2.1",
     "@push.rocks/smartlog-destination-local": "^9.0.2",
     "@push.rocks/smartlog-source-ora": "^1.0.9",
-    "@push.rocks/smartshell": "^3.3.0"
+    "@push.rocks/smartshell": "^3.3.7"
   },
   "packageManager": "pnpm@10.18.1+sha512.77a884a165cbba2d8d1c19e3b4880eee6d2fcabd0d879121e282196b80042351d5eb3ca0935fa599da1dc51265cc68816ad2bddd2a2de5ea9fdf92adbec7cd34",
   "type": "module",

readme.md

@@ -93,6 +93,7 @@ tsdocker push --no-build Dockerfile_api Dockerfile_web
 | `tsdocker test` | Build + run container test scripts (`test_*.sh`) |
 | `tsdocker login` | Authenticate with configured registries |
 | `tsdocker list` | Display discovered Dockerfiles and their dependencies |
+| `tsdocker config` | Manage global tsdocker configuration (remote builders, etc.) |
 | `tsdocker clean` | Interactively clean Docker environment |
 
 ### Build Flags
@@ -117,6 +118,24 @@ tsdocker push --no-build Dockerfile_api Dockerfile_web
 | `--registry=<url>` | Push to a single specific registry instead of all configured |
 | `--no-build` | Skip the build phase; only push existing images from local registry |
 
+### Config Subcommands
+
+| Subcommand | Description |
+|------------|-------------|
+| `add-builder` | Add or update a remote builder node |
+| `remove-builder` | Remove a remote builder by name |
+| `list-builders` | List all configured remote builders |
+| `show` | Show the full global configuration |
+
+**`add-builder` flags:**
+
+| Flag | Description |
+|------|-------------|
+| `--name=<name>` | Builder name (e.g. `arm64-builder`) |
+| `--host=<user@ip>` | SSH host (e.g. `armbuilder@192.168.1.100`) |
+| `--platform=<p>` | Target platform (e.g. `linux/arm64`) |
+| `--ssh-key=<path>` | SSH key path (optional, uses SSH agent/config by default) |
+
 ### Clean Flags
 
 | Flag | Description |
@@ -294,6 +313,51 @@ tsdocker automatically:
 - Pushes multi-platform images to the local registry via `buildx --push`
 - Copies the full manifest list (including all platform variants) to remote registries on `tsdocker push`
 
+### 🖥️ Native Remote Builders
+
+Instead of relying on slow QEMU emulation for cross-platform builds, tsdocker can use **native remote machines** via SSH as build nodes. For example, use a real arm64 machine for `linux/arm64` builds:
+
+```bash
+# Add a remote arm64 builder
+tsdocker config add-builder \
+  --name=arm64-builder \
+  --host=armbuilder@192.168.1.100 \
+  --platform=linux/arm64 \
+  --ssh-key=~/.ssh/id_ed25519
+
+# List configured builders
+tsdocker config list-builders
+
+# Remove a builder
+tsdocker config remove-builder --name=arm64-builder
+
+# Show full global config
+tsdocker config show
+```
+
+Global configuration is stored at `~/.git.zone/tsdocker/config.json`.
+
+**How it works:**
+
+When remote builders are configured and the project's `platforms` includes a matching platform, tsdocker automatically:
+
+1. Creates a **multi-node buildx builder** — local node for `linux/amd64`, remote SSH node for `linux/arm64`
+2. Opens **SSH reverse tunnels** so the remote builder can push to the local staging registry
+3. Builds natively on each platform's hardware — no QEMU overhead
+4. Tears down tunnels after the build completes
+
+```
+[Local machine]                        [Remote arm64 machine]
+  registry:2 on localhost:PORT  <──── SSH reverse tunnel ──── localhost:PORT
+  BuildKit (amd64) ──push──>            BuildKit (arm64) ──push──>
+     localhost:PORT                        localhost:PORT (tunneled)
+```
+
+**Prerequisites for the remote machine:**
+- Docker installed and running
+- A user with Docker group access (no sudo needed)
+- SSH key access configured
+
 ### ⚡ Parallel Builds
 
 Speed up builds by building independent images concurrently:

ts/00_commitinfo_data.ts

@@ -3,6 +3,6 @@
  */
 export const commitinfo = {
   name: '@git.zone/tsdocker',
-  version: '2.0.2',
+  version: '2.1.0',
   description: 'develop npm modules cross platform with docker'
 }

ts/classes.dockerfile.ts

@@ -266,12 +266,15 @@ export class Dockerfile {
   public static async buildDockerfiles(
     sortedArrayArg: Dockerfile[],
     session: TsDockerSession,
-    options?: { platform?: string; timeout?: number; noCache?: boolean; verbose?: boolean; isRootless?: boolean; parallel?: boolean; parallelConcurrency?: number },
+    options?: { platform?: string; timeout?: number; noCache?: boolean; verbose?: boolean; isRootless?: boolean; parallel?: boolean; parallelConcurrency?: number; onRegistryStarted?: () => Promise<void>; onBeforeRegistryStop?: () => Promise<void> },
   ): Promise<Dockerfile[]> {
     const total = sortedArrayArg.length;
     const overallStart = Date.now();
 
     await Dockerfile.startLocalRegistry(session, options?.isRootless);
+    if (options?.onRegistryStarted) {
+      await options.onRegistryStarted();
+    }
 
     try {
       if (options?.parallel) {
@@ -351,6 +354,9 @@ export class Dockerfile {
         }
       }
     } finally {
+      if (options?.onBeforeRegistryStop) {
+        await options.onBeforeRegistryStop();
+      }
       await Dockerfile.stopLocalRegistry(session);
     }
 

ts/classes.globalconfig.ts

@@ -0,0 +1,76 @@
+import * as fs from 'fs';
+import * as plugins from './tsdocker.plugins.js';
+import { logger } from './tsdocker.logging.js';
+import type { IGlobalConfig, IRemoteBuilder } from './interfaces/index.js';
+
+const CONFIG_DIR = plugins.path.join(
+  process.env.HOME || process.env.USERPROFILE || '~',
+  '.git.zone',
+  'tsdocker',
+);
+const CONFIG_PATH = plugins.path.join(CONFIG_DIR, 'config.json');
+
+const DEFAULT_CONFIG: IGlobalConfig = {
+  remoteBuilders: [],
+};
+
+export class GlobalConfig {
+  static getConfigPath(): string {
+    return CONFIG_PATH;
+  }
+
+  static load(): IGlobalConfig {
+    try {
+      const raw = fs.readFileSync(CONFIG_PATH, 'utf-8');
+      const parsed = JSON.parse(raw);
+      return {
+        ...DEFAULT_CONFIG,
+        ...parsed,
+      };
+    } catch {
+      return { ...DEFAULT_CONFIG };
+    }
+  }
+
+  static save(config: IGlobalConfig): void {
+    fs.mkdirSync(CONFIG_DIR, { recursive: true });
+    fs.writeFileSync(CONFIG_PATH, JSON.stringify(config, null, 2) + '\n', 'utf-8');
+  }
+
+  static addBuilder(builder: IRemoteBuilder): void {
+    const config = GlobalConfig.load();
+    const existing = config.remoteBuilders.findIndex((b) => b.name === builder.name);
+    if (existing >= 0) {
+      config.remoteBuilders[existing] = builder;
+      logger.log('info', `Updated remote builder: ${builder.name}`);
+    } else {
+      config.remoteBuilders.push(builder);
+      logger.log('info', `Added remote builder: ${builder.name}`);
+    }
+    GlobalConfig.save(config);
+  }
+
+  static removeBuilder(name: string): void {
+    const config = GlobalConfig.load();
+    const before = config.remoteBuilders.length;
+    config.remoteBuilders = config.remoteBuilders.filter((b) => b.name !== name);
+    if (config.remoteBuilders.length < before) {
+      logger.log('info', `Removed remote builder: ${name}`);
+    } else {
+      logger.log('warn', `Remote builder not found: ${name}`);
+    }
+    GlobalConfig.save(config);
+  }
+
+  static getBuilders(): IRemoteBuilder[] {
+    return GlobalConfig.load().remoteBuilders;
+  }
+
+  /**
+   * Returns remote builders that match any of the requested platforms
+   */
+  static getBuildersForPlatforms(platforms: string[]): IRemoteBuilder[] {
+    const builders = GlobalConfig.getBuilders();
+    return builders.filter((b) => platforms.includes(b.platform));
+  }
+}

ts/classes.sshtunnel.ts

@@ -0,0 +1,77 @@
+import * as plugins from './tsdocker.plugins.js';
+import { logger } from './tsdocker.logging.js';
+import type { IRemoteBuilder } from './interfaces/index.js';
+
+const smartshellInstance = new plugins.smartshell.Smartshell({
+  executor: 'bash',
+});
+
+/**
+ * Manages SSH reverse tunnels for remote builder nodes.
+ * Opens tunnels so that the local staging registry (localhost:<port>)
+ * is accessible as localhost:<port> on each remote machine.
+ */
+export class SshTunnelManager {
+  private tunnelPids: number[] = [];
+
+  /**
+   * Opens a reverse SSH tunnel to make localPort accessible on the remote machine.
+   * ssh -f -N -o StrictHostKeyChecking=no -o ExitOnForwardFailure=yes
+   *     -R <localPort>:localhost:<localPort> [-i keyPath] user@host
+   */
+  async openTunnel(builder: IRemoteBuilder, localPort: number): Promise<void> {
+    const keyOpt = builder.sshKeyPath ? `-i ${builder.sshKeyPath} ` : '';
+    const cmd = [
+      'ssh -f -N',
+      '-o StrictHostKeyChecking=no',
+      '-o ExitOnForwardFailure=yes',
+      `-R ${localPort}:localhost:${localPort}`,
+      `${keyOpt}${builder.host}`,
+    ].join(' ');
+
+    logger.log('info', `Opening SSH tunnel to ${builder.host} for port ${localPort}...`);
+    const result = await smartshellInstance.exec(cmd);
+
+    if (result.exitCode !== 0) {
+      throw new Error(
+        `Failed to open SSH tunnel to ${builder.host}: ${result.stderr || 'unknown error'}`
+      );
+    }
+
+    // Find the PID of the tunnel process we just started
+    const pidResult = await smartshellInstance.exec(
+      `pgrep -f "ssh.*-R ${localPort}:localhost:${localPort}.*${builder.host}" | tail -1`
+    );
+    if (pidResult.exitCode === 0 && pidResult.stdout.trim()) {
+      const pid = parseInt(pidResult.stdout.trim(), 10);
+      if (!isNaN(pid)) {
+        this.tunnelPids.push(pid);
+        logger.log('ok', `SSH tunnel to ${builder.host} established (PID ${pid})`);
+      }
+    }
+  }
+
+  /**
+   * Opens tunnels for all provided remote builders
+   */
+  async openTunnels(builders: IRemoteBuilder[], localPort: number): Promise<void> {
+    for (const builder of builders) {
+      await this.openTunnel(builder, localPort);
+    }
+  }
+
+  /**
+   * Closes all tunnel processes
+   */
+  async closeAll(): Promise<void> {
+    for (const pid of this.tunnelPids) {
+      try {
+        process.kill(pid, 'SIGTERM');
+        logger.log('info', `Closed SSH tunnel (PID ${pid})`);
+      } catch {
+        // Process may have already exited
+      }
+    }
+    this.tunnelPids = [];
+  }
+}

ts/classes.tsdockermanager.ts

@@ -8,7 +8,9 @@ import { TsDockerCache } from './classes.tsdockercache.js';
 import { DockerContext } from './classes.dockercontext.js';
 import { TsDockerSession } from './classes.tsdockersession.js';
 import { RegistryCopy } from './classes.registrycopy.js';
-import type { ITsDockerConfig, IBuildCommandOptions } from './interfaces/index.js';
+import { GlobalConfig } from './classes.globalconfig.js';
+import { SshTunnelManager } from './classes.sshtunnel.js';
+import type { ITsDockerConfig, IBuildCommandOptions, IRemoteBuilder } from './interfaces/index.js';
 
 const smartshellInstance = new plugins.smartshell.Smartshell({
   executor: 'bash',
@@ -24,6 +26,8 @@ export class TsDockerManager {
   public dockerContext: DockerContext;
   public session!: TsDockerSession;
   private dockerfiles: Dockerfile[] = [];
+  private activeRemoteBuilders: IRemoteBuilder[] = [];
+  private sshTunnelManager?: SshTunnelManager;
 
   constructor(config: ITsDockerConfig) {
     this.config = config;
@@ -235,6 +239,7 @@ export class TsDockerManager {
       const total = toBuild.length;
       const overallStart = Date.now();
       await Dockerfile.startLocalRegistry(this.session, this.dockerContext.contextInfo?.isRootless);
+      await this.openRemoteTunnels();
 
       try {
         if (options?.parallel) {
@@ -332,6 +337,7 @@ export class TsDockerManager {
           }
         }
       } finally {
+        await this.closeRemoteTunnels();
         await Dockerfile.stopLocalRegistry(this.session);
       }
 
@@ -347,6 +353,8 @@ export class TsDockerManager {
         isRootless: this.dockerContext.contextInfo?.isRootless,
         parallel: options?.parallel,
         parallelConcurrency: options?.parallelConcurrency,
+        onRegistryStarted: () => this.openRemoteTunnels(),
+        onBeforeRegistryStop: () => this.closeRemoteTunnels(),
       });
     }
 
@@ -373,13 +381,76 @@ export class TsDockerManager {
   }
 
   /**
-   * Ensures Docker buildx is set up for multi-architecture builds
+   * Ensures Docker buildx is set up for multi-architecture builds.
+   * When remote builders are configured in the global config, creates a multi-node
+   * builder with native nodes instead of relying on QEMU emulation.
    */
   private async ensureBuildx(): Promise<void> {
     const builderName = this.dockerContext.getBuilderName() + (this.session?.config.builderSuffix || '');
     const platforms = this.config.platforms?.join(', ') || 'default';
     logger.log('info', `Setting up Docker buildx [${platforms}]...`);
     logger.log('info', `Builder: ${builderName}`);
+
+    // Check for remote builders matching our target platforms
+    const requestedPlatforms = this.config.platforms || ['linux/amd64'];
+    const remoteBuilders = GlobalConfig.getBuildersForPlatforms(requestedPlatforms);
+
+    if (remoteBuilders.length > 0) {
+      await this.ensureBuildxWithRemoteNodes(builderName, requestedPlatforms, remoteBuilders);
+    } else {
+      await this.ensureBuildxLocal(builderName);
+    }
+
+    logger.log('ok', `Docker buildx ready (builder: ${builderName}, platforms: ${platforms})`);
+  }
+
+  /**
+   * Creates a multi-node buildx builder with local + remote SSH nodes.
+   */
+  private async ensureBuildxWithRemoteNodes(
+    builderName: string,
+    requestedPlatforms: string[],
+    remoteBuilders: IRemoteBuilder[],
+  ): Promise<void> {
+    const remotePlatforms = new Set(remoteBuilders.map((b) => b.platform));
+    const localPlatforms = requestedPlatforms.filter((p) => !remotePlatforms.has(p));
+
+    logger.log('info', `Remote builders: ${remoteBuilders.map((b) => `${b.name} (${b.platform} @ ${b.host})`).join(', ')}`);
+    if (localPlatforms.length > 0) {
+      logger.log('info', `Local platforms: ${localPlatforms.join(', ')}`);
+    }
+
+    // Always recreate the builder to ensure correct node topology
+    await smartshellInstance.execSilent(`docker buildx rm ${builderName} 2>/dev/null || true`);
+
+    // Create the local node
+    const localPlatformFlag = localPlatforms.length > 0 ? ` --platform ${localPlatforms.join(',')}` : '';
+    await smartshellInstance.exec(
+      `docker buildx create --name ${builderName} --driver docker-container --driver-opt network=host${localPlatformFlag} --use`
+    );
+
+    // Append remote nodes
+    for (const builder of remoteBuilders) {
+      logger.log('info', `Appending remote node: ${builder.name} (${builder.platform}) via ssh://${builder.host}`);
+      const appendResult = await smartshellInstance.exec(
+        `docker buildx create --append --name ${builderName} --driver docker-container --driver-opt network=host --platform ${builder.platform} --node ${builder.name} ssh://${builder.host}`
+      );
+      if (appendResult.exitCode !== 0) {
+        throw new Error(`Failed to append remote builder ${builder.name}: ${appendResult.stderr}`);
+      }
+    }
+
+    // Bootstrap all nodes
+    await smartshellInstance.exec('docker buildx inspect --bootstrap');
+
+    // Store active remote builders for SSH tunnel setup during build
+    this.activeRemoteBuilders = remoteBuilders;
+  }
+
+  /**
+   * Creates a single-node local buildx builder (original behavior, uses QEMU for cross-platform).
+   */
+  private async ensureBuildxLocal(builderName: string): Promise<void> {
     const inspectResult = await smartshellInstance.exec(`docker buildx inspect ${builderName} 2>/dev/null`);
 
     if (inspectResult.exitCode !== 0) {
@@ -401,7 +472,30 @@ export class TsDockerManager {
         await smartshellInstance.exec(`docker buildx use ${builderName}`);
       }
     }
-    logger.log('ok', `Docker buildx ready (builder: ${builderName}, platforms: ${platforms})`);
+    this.activeRemoteBuilders = [];
+  }
+
+  /**
+   * Opens SSH reverse tunnels for remote builders so they can reach the local registry.
+   */
+  private async openRemoteTunnels(): Promise<void> {
+    if (this.activeRemoteBuilders.length === 0) return;
+
+    this.sshTunnelManager = new SshTunnelManager();
+    await this.sshTunnelManager.openTunnels(
+      this.activeRemoteBuilders,
+      this.session.config.registryPort,
+    );
+  }
+
+  /**
+   * Closes any active SSH tunnels.
+   */
+  private async closeRemoteTunnels(): Promise<void> {
+    if (this.sshTunnelManager) {
+      await this.sshTunnelManager.closeAll();
+      this.sshTunnelManager = undefined;
+    }
   }
 
   /**

ts/interfaces/index.ts

@@ -95,3 +95,20 @@ export interface IDockerContextInfo {
   dockerHost?: string;   // value of DOCKER_HOST env var, if set
   topology?: 'socket-mount' | 'dind' | 'local';
 }
+
+/**
+ * A remote builder node for native cross-platform builds
+ */
+export interface IRemoteBuilder {
+  name: string;        // e.g., "arm64-builder"
+  host: string;        // e.g., "armbuilder@192.168.190.216"
+  platform: string;    // e.g., "linux/arm64"
+  sshKeyPath?: string; // e.g., "~/.ssh/id_ed25519"
+}
+
+/**
+ * Global tsdocker configuration stored at ~/.git.zone/tsdocker/config.json
+ */
+export interface IGlobalConfig {
+  remoteBuilders: IRemoteBuilder[];
+}

ts/tsdocker.cli.ts

@@ -7,6 +7,7 @@ import * as ConfigModule from './tsdocker.config.js';
 import { logger, ora } from './tsdocker.logging.js';
 import { TsDockerManager } from './classes.tsdockermanager.js';
 import { DockerContext } from './classes.dockercontext.js';
+import { GlobalConfig } from './classes.globalconfig.js';
 import type { IBuildCommandOptions } from './interfaces/index.js';
 import { commitinfo } from './00_commitinfo_data.js';
 
@@ -33,6 +34,7 @@ COMMANDS
     test    [flags]                  Build and run container test scripts
     login                            Authenticate with configured registries
     list                             List discovered Dockerfiles
+    config  <subcommand> [flags]     Manage global tsdocker configuration
     clean   [-y] [--all]             Interactive Docker resource cleanup
 
 BUILD / PUSH OPTIONS
@@ -52,6 +54,17 @@ CLEAN OPTIONS
     -y                  Auto-confirm all prompts
     --all               Include all images and volumes (not just dangling)
 
+CONFIG SUBCOMMANDS
+    add-builder         Add a remote builder node
+      --name=<n>          Builder name (e.g. arm64-builder)
+      --host=<h>          SSH host (e.g. user@192.168.1.100)
+      --platform=<p>      Platform (e.g. linux/arm64)
+      --ssh-key=<path>    SSH key path (optional)
+    remove-builder      Remove a remote builder by name
+      --name=<n>          Builder name to remove
+    list-builders       List all configured remote builders
+    show                Show full global config
+
 CONFIGURATION
     Configure via npmextra.json under the "@git.zone/tsdocker" key:
 
@@ -62,12 +75,17 @@ CONFIGURATION
       push              Boolean, auto-push after build
       testDir           Directory containing test_*.sh scripts
 
+    Global config is stored at ~/.git.zone/tsdocker/config.json
+    and managed via the "config" command.
+
 EXAMPLES
     tsdocker build
     tsdocker build Dockerfile_app --platform=linux/arm64
     tsdocker push --registry=ghcr.io
     tsdocker test --verbose
     tsdocker clean -y --all
+    tsdocker config add-builder --name=arm64 --host=user@host --platform=linux/arm64
+    tsdocker config list-builders
 `;
   console.log(manPage);
 };
@@ -280,6 +298,76 @@ export let run = () => {
     }
   });
 
+  /**
+   * Manage global tsdocker configuration (remote builders, etc.)
+   * Usage: tsdocker config <subcommand> [--name=...] [--host=...] [--platform=...] [--ssh-key=...]
+   */
+  tsdockerCli.addCommand('config').subscribe(async argvArg => {
+    try {
+      const subcommand = argvArg._[1] as string;
+
+      switch (subcommand) {
+        case 'add-builder': {
+          const name = argvArg.name as string;
+          const host = argvArg.host as string;
+          const platform = argvArg.platform as string;
+          const sshKeyPath = argvArg['ssh-key'] as string | undefined;
+
+          if (!name || !host || !platform) {
+            logger.log('error', 'Required: --name, --host, --platform');
+            logger.log('info', 'Usage: tsdocker config add-builder --name=arm64-builder --host=user@host --platform=linux/arm64 [--ssh-key=~/.ssh/id_ed25519]');
+            process.exit(1);
+          }
+
+          GlobalConfig.addBuilder({ name, host, platform, sshKeyPath });
+          logger.log('success', `Remote builder "${name}" configured: ${platform} via ssh://${host}`);
+          break;
+        }
+
+        case 'remove-builder': {
+          const name = argvArg.name as string;
+          if (!name) {
+            logger.log('error', 'Required: --name');
+            logger.log('info', 'Usage: tsdocker config remove-builder --name=arm64-builder');
+            process.exit(1);
+          }
+          GlobalConfig.removeBuilder(name);
+          logger.log('success', `Remote builder "${name}" removed`);
+          break;
+        }
+
+        case 'list-builders': {
+          const builders = GlobalConfig.getBuilders();
+          if (builders.length === 0) {
+            logger.log('info', 'No remote builders configured');
+          } else {
+            logger.log('info', `${builders.length} remote builder(s):`);
+            for (const b of builders) {
+              const keyInfo = b.sshKeyPath ? ` (key: ${b.sshKeyPath})` : '';
+              logger.log('info', `  ${b.name}: ${b.platform} via ssh://${b.host}${keyInfo}`);
+            }
+          }
+          break;
+        }
+
+        case 'show': {
+          const config = GlobalConfig.load();
+          logger.log('info', `Config file: ${GlobalConfig.getConfigPath()}`);
+          console.log(JSON.stringify(config, null, 2));
+          break;
+        }
+
+        default:
+          logger.log('error', `Unknown config subcommand: ${subcommand || '(none)'}`);
+          logger.log('info', 'Available: add-builder, remove-builder, list-builders, show');
+          process.exit(1);
+      }
+    } catch (err) {
+      logger.log('error', `Config failed: ${(err as Error).message}`);
+      process.exit(1);
+    }
+  });
+
   tsdockerCli.addCommand('clean').subscribe(async argvArg => {
     try {
       const autoYes = !!argvArg.y;