diff --git a/packages/cli-module-build/src/lib/runner/runBackend.test.ts b/packages/cli-module-build/src/lib/runner/runBackend.test.ts
index b4193cad52..6fd9f965aa 100644
--- a/packages/cli-module-build/src/lib/runner/runBackend.test.ts
+++ b/packages/cli-module-build/src/lib/runner/runBackend.test.ts
@@ -51,17 +51,9 @@ jest.mock('ctrlc-windows', () => ({
 
 jest.mock('@backstage/config-loader', () => ({
   ConfigSources: {
-    default: () => ({
-      readConfigData: async function* readConfigData() {
-        yield { configs: [] };
-      },
-    }),
-  },
-}));
-
-jest.mock('@backstage/config', () => ({
-  ConfigReader: {
-    fromConfigs: () => ({
+    default: () => ({}),
+    toConfig: async () => ({
+      close: jest.fn(),
       getOptionalString: () => undefined,
     }),
   },
diff --git a/packages/cli-module-build/src/lib/runner/runBackend.ts b/packages/cli-module-build/src/lib/runner/runBackend.ts
index c0c88e42db..40124d39a0 100644
--- a/packages/cli-module-build/src/lib/runner/runBackend.ts
+++ b/packages/cli-module-build/src/lib/runner/runBackend.ts
@@ -26,7 +26,6 @@ import {
 } from 'node:path';
 import { targetPaths } from '@backstage/cli-common';
 import { ConfigSources } from '@backstage/config-loader';
-import { ConfigReader } from '@backstage/config';
 
 import spawn from 'cross-spawn';
 import { startEmbeddedDb } from './startEmbeddedDb';
@@ -229,14 +228,7 @@ async function readDatabaseClient(
     ]),
   });
 
-  const abortController = new AbortController();
-  for await (const { configs } of source.readConfigData({
-    signal: abortController.signal,
-  })) {
-    abortController.abort();
-    return ConfigReader.fromConfigs(configs).getOptionalString(
-      'backend.database.client',
-    );
-  }
-  return undefined;
+  const config = await ConfigSources.toConfig(source);
+  config.close();
+  return config.getOptionalString('backend.database.client');
 }