diff --git a/plugins/proxy-backend/package.json b/plugins/proxy-backend/package.json
index 1ca6cbe5f5..3d3ccfaa0d 100644
--- a/plugins/proxy-backend/package.json
+++ b/plugins/proxy-backend/package.json
@@ -71,13 +71,11 @@
     "@backstage/config-loader": "workspace:^",
     "@backstage/errors": "workspace:^",
     "@types/http-proxy-middleware": "^1.0.0",
-    "@types/supertest": "^2.0.8",
     "@types/uuid": "^9.0.0",
     "@types/yup": "^0.32.0",
     "msw": "^2.0.0",
     "node-fetch": "^2.6.7",
-    "portfinder": "^1.0.32",
-    "supertest": "^6.1.3"
+    "portfinder": "^1.0.32"
   },
   "configSchema": "config.d.ts"
 }
diff --git a/plugins/proxy-backend/src/service/router.config.test.ts b/plugins/proxy-backend/src/service/router.config.test.ts
index 20aed5452a..c868092612 100644
--- a/plugins/proxy-backend/src/service/router.config.test.ts
+++ b/plugins/proxy-backend/src/service/router.config.test.ts
@@ -14,51 +14,46 @@
  * limitations under the License.
  */
 
+import { createBackend } from '@backstage/backend-defaults';
 import {
-  HostDiscovery,
-  loggerToWinstonLogger,
-} from '@backstage/backend-common';
+  coreServices,
+  createServiceFactory,
+} from '@backstage/backend-plugin-api';
+import {
+  mockServices,
+  setupRequestMockHandlers,
+} from '@backstage/backend-test-utils';
 import {
   ConfigSources,
   MutableConfigSource,
   StaticConfigSource,
 } from '@backstage/config-loader';
-import express from 'express';
-import { http, HttpResponse } from 'msw';
+import { HttpResponse, http, passthrough } from 'msw';
 import { setupServer } from 'msw/node';
-import request from 'supertest';
-import { createRouter } from './router';
-import { mockServices } from '@backstage/backend-test-utils';
+import fetch from 'node-fetch';
+import portFinder from 'portfinder';
 
 // this test is stored in its own file to work around the mocked
 // http-proxy-middleware module used in the main test file
 
 describe('createRouter reloadable configuration', () => {
-  const server = setupServer(
-    http.get('https://non-existing-example.com/', req =>
-      HttpResponse.json({
-        url: req.request.url.toString(),
-        headers: req.request.headers,
-      }),
-    ),
-  );
-
-  beforeAll(() =>
-    server.listen({
-      onUnhandledRequest: ({ headers }, print) => {
-        if (headers.get('User-Agent') === 'supertest') {
-          return;
-        }
-        print.error();
-      },
-    }),
-  );
-
-  afterAll(() => server.close());
-  afterEach(() => server.resetHandlers());
+  const server = setupServer();
+  setupRequestMockHandlers(server);
 
   it('should be able to observe the config', async () => {
-    const logger = loggerToWinstonLogger(mockServices.logger.mock());
+    const host = 'localhost';
+    const port = await portFinder.getPortPromise({ host });
+    const baseUrl = `http://${host}:${port}`;
+
+    server.use(
+      http.all(`${baseUrl}/*`, passthrough),
+      http.get('https://non-existing-example.com/*', req =>
+        HttpResponse.json({
+          url: req.request.url.toString(),
+          headers: req.request.headers,
+        }),
+      ),
+    );
 
     // Grab the subscriber function and use mutable config data to mock a config file change
     const mutableConfigSource = MutableConfigSource.create({ data: {} });
@@ -67,18 +62,14 @@ describe('createRouter reloadable configuration', () => {
         StaticConfigSource.create({
           data: {
             backend: {
-              baseUrl: 'http://localhost:7007',
-              listen: {
-                port: 7007,
-              },
+              baseUrl,
+              listen: { host, port },
             },
             proxy: {
               endpoints: {
                 '/test': {
                   target: 'https://non-existing-example.com',
-                  pathRewrite: {
-                    '.*': '/',
-                  },
+                  credentials: 'dangerously-allow-unauthenticated',
                 },
               },
             },
@@ -88,40 +79,38 @@ describe('createRouter reloadable configuration', () => {
       ]),
     );
 
-    const discovery = HostDiscovery.fromConfig(config);
-    const router = await createRouter({
-      config,
-      logger,
-      discovery,
+    const backend = createBackend();
+    backend.add(import('../alpha'));
+    backend.add(
+      createServiceFactory({
+        service: coreServices.rootConfig,
+        deps: {},
+        factory: () => config,
+      }),
+    );
+    backend.add(mockServices.rootLogger.factory());
+    await backend.start();
+
+    await expect(fetch(`${baseUrl}/api/proxy/test`)).resolves.toMatchObject({
+      status: 200,
     });
-    expect(router).toBeDefined();
-
-    const app = express();
-    app.use(router);
-
-    const agent = request.agent(app);
-    // this is set to let msw pass test requests through the mock server
-    agent.set('User-Agent', 'supertest');
-
-    const response1 = await agent.get('/test');
-
-    expect(response1.status).toEqual(200);
+    await expect(
+      fetch(`${baseUrl}/api/proxy/test2`),
+    ).resolves.not.toMatchObject({ status: 200 });
 
     mutableConfigSource.setData({
       proxy: {
         endpoints: {
           '/test2': {
             target: 'https://non-existing-example.com',
-            pathRewrite: {
-              '.*': '/',
-            },
+            credentials: 'dangerously-allow-unauthenticated',
           },
         },
       },
     });
 
-    const response2 = await agent.get('/test2');
-
-    expect(response2.status).toEqual(200);
+    await expect(fetch(`${baseUrl}/api/proxy/test2`)).resolves.toMatchObject({
+      status: 200,
+    });
   });
 });
diff --git a/plugins/proxy-backend/src/service/router.credentials.test.ts b/plugins/proxy-backend/src/service/router.credentials.test.ts
index 85fad9f038..53d0f157f3 100644
--- a/plugins/proxy-backend/src/service/router.credentials.test.ts
+++ b/plugins/proxy-backend/src/service/router.credentials.test.ts
@@ -35,7 +35,7 @@ describe('credentials', () => {
 
   it('handles all valid credentials settings', async () => {
     const host = 'localhost';
-    const port = await portFinder.getPortPromise();
+    const port = await portFinder.getPortPromise({ host });
     const baseUrl = `http://${host}:${port}`;
 
     const config = {
@@ -82,7 +82,7 @@ describe('credentials', () => {
     };
 
     worker.use(
-      http.all(`${baseUrl}/*`, () => passthrough()),
+      http.all(`${baseUrl}/*`, passthrough),
       http.get('http://target.com/*', req => {
         const auth = req.request.headers.get('authorization');
         return HttpResponse.json({
diff --git a/yarn.lock b/yarn.lock
index a823457dce..3288ed9a2e 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -6464,7 +6464,6 @@ __metadata:
     "@backstage/types": "workspace:^"
     "@types/express": ^4.17.6
     "@types/http-proxy-middleware": ^1.0.0
-    "@types/supertest": ^2.0.8
     "@types/uuid": ^9.0.0
     "@types/yup": ^0.32.0
     express: ^4.17.1
@@ -6474,7 +6473,6 @@ __metadata:
     msw: ^2.0.0
     node-fetch: ^2.6.7
     portfinder: ^1.0.32
-    supertest: ^6.1.3
     uuid: ^9.0.0
     winston: ^3.2.1
     yaml: ^2.0.0