diff --git a/test/api-server_test.ts b/test/api-server_test.ts
index 55588f1..2a7fd2f 100644
--- a/test/api-server_test.ts
+++ b/test/api-server_test.ts
@@ -47,15 +47,14 @@ Deno.test('ApiServer serves health metrics and authenticated model listings', as
         };
       },
     } as never,
-  );
-
-  (server as unknown as {
-    gpuDetector: { detectGpus: () => Promise<unknown[]> };
-  }).gpuDetector = {
-    async detectGpus() {
-      return [{ id: 'nvidia-0' }];
+    {
+      gpuDetector: {
+        async detectGpus() {
+          return [{ id: 'nvidia-0' }];
+        },
+      } as never,
     },
-  };
+  );
 
   await server.start();
 
@@ -142,15 +141,14 @@ Deno.test('ApiServer metrics expose 5xx counts for failing endpoints', async ()
         };
       },
     } as never,
-  );
-
-  (server as unknown as {
-    gpuDetector: { detectGpus: () => Promise<unknown[]> };
-  }).gpuDetector = {
-    async detectGpus() {
-      return [];
+    {
+      gpuDetector: {
+        async detectGpus() {
+          return [];
+        },
+      } as never,
     },
-  };
+  );
 
   await server.start();
 
@@ -209,15 +207,14 @@ Deno.test('ApiServer enforces api rate limits while exempting health and metrics
         };
       },
     } as never,
-  );
-
-  (server as unknown as {
-    gpuDetector: { detectGpus: () => Promise<unknown[]> };
-  }).gpuDetector = {
-    async detectGpus() {
-      return [];
+    {
+      gpuDetector: {
+        async detectGpus() {
+          return [];
+        },
+      } as never,
     },
-  };
+  );
 
   await server.start();
 
diff --git a/ts/api/server.ts b/ts/api/server.ts
index d26aecc..eefdfeb 100644
--- a/ts/api/server.ts
+++ b/ts/api/server.ts
@@ -17,6 +17,12 @@ import { ModelLoader } from '../models/loader.ts';
 import { GpuDetector } from '../hardware/gpu-detector.ts';
 import { ClusterHandler } from './handlers/cluster.ts';
 
+interface IApiServerOptions {
+  gpuDetector?: GpuDetector;
+  router?: ApiRouter;
+  clusterHandler?: ClusterHandler;
+}
+
 /**
  * API Server for ModelGrid
  */
@@ -42,15 +48,16 @@ export class ApiServer {
     modelRegistry: ModelRegistry,
     modelLoader: ModelLoader,
     clusterCoordinator: ClusterCoordinator,
+    options: IApiServerOptions = {},
   ) {
     this.config = config;
     this.containerManager = containerManager;
     this.modelRegistry = modelRegistry;
-    this.gpuDetector = new GpuDetector();
+    this.gpuDetector = options.gpuDetector || new GpuDetector();
     this.modelLoader = modelLoader;
     this.clusterCoordinator = clusterCoordinator;
-    this.clusterHandler = new ClusterHandler(clusterCoordinator);
-    this.router = new ApiRouter(
+    this.clusterHandler = options.clusterHandler || new ClusterHandler(clusterCoordinator);
+    this.router = options.router || new ApiRouter(
       containerManager,
       modelRegistry,
       this.modelLoader,