diff --git a/packages/frontend-plugin-api/src/components/ExtensionBoundary.test.tsx b/packages/frontend-plugin-api/src/components/ExtensionBoundary.test.tsx
index 1f12f127e8..403d591db1 100644
--- a/packages/frontend-plugin-api/src/components/ExtensionBoundary.test.tsx
+++ b/packages/frontend-plugin-api/src/components/ExtensionBoundary.test.tsx
@@ -30,24 +30,26 @@ import {
 } from '@backstage/core-plugin-api';
 import { createRouteRef } from '../routing';
 import { createExtensionTester } from '@backstage/frontend-test-utils';
-import { createApiExtension } from '../extensions';
+import { ApiBlueprint } from '../blueprints';
 
 const wrapInBoundaryExtension = (element?: JSX.Element) => {
   const routeRef = createRouteRef();
   return createExtension({
     name: 'test',
     attachTo: { id: 'app/routes', input: 'routes' },
-    output: {
-      element: coreExtensionData.reactElement,
-      path: coreExtensionData.routePath,
-      routeRef: coreExtensionData.routeRef.optional(),
-    },
+    output: [
+      coreExtensionData.reactElement,
+      coreExtensionData.routePath,
+      coreExtensionData.routeRef.optional(),
+    ],
     factory({ node }) {
-      return {
-        routeRef,
-        path: '/',
-        element: <ExtensionBoundary node={node}>{element}</ExtensionBoundary>,
-      };
+      return [
+        coreExtensionData.reactElement(
+          <ExtensionBoundary node={node}>{element}</ExtensionBoundary>,
+        ),
+        coreExtensionData.routePath('/'),
+        coreExtensionData.routeRef(routeRef),
+      ];
     },
   });
 };
@@ -134,8 +136,11 @@ describe('ExtensionBoundary', () => {
     await act(async () => {
       createExtensionTester(wrapInBoundaryExtension(<Emitter />))
         .add(
-          createApiExtension({
-            factory: createApiFactory(analyticsApiRef, analyticsApiMock),
+          ApiBlueprint.make({
+            namespace: analyticsApiRef.id,
+            params: {
+              factory: createApiFactory(analyticsApiRef, analyticsApiMock),
+            },
           }),
         )
         .render();
diff --git a/packages/frontend-test-utils/src/app/createExtensionTester.test.tsx b/packages/frontend-test-utils/src/app/createExtensionTester.test.tsx
index 73220419b7..86953df675 100644
--- a/packages/frontend-test-utils/src/app/createExtensionTester.test.tsx
+++ b/packages/frontend-test-utils/src/app/createExtensionTester.test.tsx
@@ -41,8 +41,8 @@ describe('createExtensionTester', () => {
   const defaultDefinition = {
     namespace: 'test',
     attachTo: { id: 'ignored', input: 'ignored' },
-    output: { element: coreExtensionData.reactElement },
-    factory: () => ({ element: <div>test</div> }),
+    output: [coreExtensionData.reactElement],
+    factory: () => [coreExtensionData.reactElement(<div>test</div>)],
   };
 
   it('should render a simple extension', async () => {
@@ -77,23 +77,23 @@ describe('createExtensionTester', () => {
   it('should render multiple extensions', async () => {
     const indexPageExtension = createExtension({
       ...defaultDefinition,
-      factory: () => ({
-        element: (
+      factory: () => [
+        coreExtensionData.reactElement(
           <div>
             Index page <Link to="/details">See details</Link>
-          </div>
+          </div>,
         ),
-      }),
+      ],
     });
     const detailsPageExtension = createExtension({
       ...defaultDefinition,
       name: 'details',
       attachTo: { id: 'app/routes', input: 'routes' },
-      output: {
-        path: coreExtensionData.routePath,
-        element: coreExtensionData.reactElement,
-      },
-      factory: () => ({ path: '/details', element: <div>Details page</div> }),
+      output: [coreExtensionData.routePath, coreExtensionData.reactElement],
+      factory: () => [
+        coreExtensionData.routePath('/details'),
+        coreExtensionData.reactElement(<div>Details page</div>),
+      ],
     });
 
     const tester = createExtensionTester(indexPageExtension);
@@ -112,9 +112,11 @@ describe('createExtensionTester', () => {
   it('should accepts a custom config', async () => {
     const indexPageExtension = createExtension({
       ...defaultDefinition,
-      configSchema: createSchemaFromZod(z =>
-        z.object({ title: z.string().optional() }),
-      ),
+      config: {
+        schema: {
+          title: z => z.string().optional(),
+        },
+      },
       factory: ({ config }) => {
         const Component = () => {
           const configApi = useApi(configApiRef);
@@ -127,9 +129,8 @@ describe('createExtensionTester', () => {
             </div>
           );
         };
-        return {
-          element: <Component />,
-        };
+
+        return [coreExtensionData.reactElement(<Component />)];
       },
     });
 
@@ -137,17 +138,18 @@ describe('createExtensionTester', () => {
       ...defaultDefinition,
       name: 'details',
       attachTo: { id: 'app/routes', input: 'routes' },
-      configSchema: createSchemaFromZod(z =>
-        z.object({ title: z.string().optional() }),
-      ),
-      output: {
-        path: coreExtensionData.routePath,
-        element: coreExtensionData.reactElement,
+      config: {
+        schema: {
+          title: z => z.string().optional(),
+        },
       },
-      factory: ({ config }) => ({
-        path: '/details',
-        element: <div>{config.title ?? 'Details page'}</div>,
-      }),
+      output: [coreExtensionData.routePath, coreExtensionData.reactElement],
+      factory: ({ config }) => [
+        coreExtensionData.routePath('/details'),
+        coreExtensionData.reactElement(
+          <div>{config.title ?? 'Details page'}</div>,
+        ),
+      ],
     });
 
     const tester = createExtensionTester(indexPageExtension, {
@@ -209,9 +211,7 @@ describe('createExtensionTester', () => {
           );
         };
 
-        return {
-          element: <Component />,
-        };
+        return [coreExtensionData.reactElement(<Component />)];
       },
     });
 
@@ -254,16 +254,16 @@ describe('createExtensionTester', () => {
       namespace: 'test',
       name: 'e1',
       attachTo: { id: 'ignored', input: 'ignored' },
-      output: { text: stringDataRef },
-      factory: () => ({ text: 'test-text' }),
+      output: [stringDataRef],
+      factory: () => [stringDataRef('test-text')],
     });
 
     const extension2 = createExtension({
       namespace: 'test',
       name: 'e2',
       attachTo: { id: 'ignored', input: 'ignored' },
-      output: { text: stringDataRef },
-      factory: () => ({ text: 'test-text' }),
+      output: [stringDataRef],
+      factory: () => [stringDataRef('test-text')],
     });
 
     const tester = createExtensionTester(extension);
@@ -278,16 +278,16 @@ describe('createExtensionTester', () => {
       namespace: 'test',
       name: 'e1',
       attachTo: { id: 'ignored', input: 'ignored' },
-      output: { text: stringDataRef },
-      factory: () => ({ text: 'test-text' }),
+      output: [stringDataRef],
+      factory: () => [stringDataRef('test-text')],
     });
 
     const extension2 = createExtension({
       namespace: 'test',
       name: 'e2',
       attachTo: { id: 'ignored', input: 'ignored' },
-      output: { text: stringDataRef },
-      factory: () => ({ text: 'test-text' }),
+      output: [stringDataRef],
+      factory: () => [stringDataRef('test-text')],
     });
 
     const tester = createExtensionTester(extension).add(extension2);
@@ -377,26 +377,21 @@ describe('createExtensionTester', () => {
       namespace: 'test',
       name: 'e1',
       attachTo: { id: 'ignored', input: 'ignored' },
-      output: { text: stringDataRef },
+      output: [stringDataRef],
       inputs: {
-        input: createExtensionInput(
-          {
-            output: stringDataRef,
-          },
-          { singleton: true },
-        ),
+        input: createExtensionInput([stringDataRef], { singleton: true }),
       },
-      factory: ({ inputs }) => ({
-        text: `nest-${inputs.input.output.output}`,
-      }),
+      factory: ({ inputs }) => [
+        stringDataRef(`nest-${inputs.input.get(stringDataRef)}`),
+      ],
     });
 
     const extension2 = createExtension({
       namespace: 'test',
       name: 'e2',
       attachTo: { id: 'test/e1', input: 'blob' },
-      output: { text: stringDataRef },
-      factory: () => ({ text: 'test-text' }),
+      output: [stringDataRef],
+      factory: () => [stringDataRef('test-text')],
     });
 
     const tester = createExtensionTester(extension).add(extension2);
@@ -418,18 +413,13 @@ describe('createExtensionTester', () => {
       namespace: 'test',
       name: 'e1',
       attachTo: { id: 'ignored', input: 'ignored' },
-      output: { text: stringDataRef },
+      output: [stringDataRef],
       inputs: {
-        input: createExtensionInput(
-          {
-            output: stringDataRef,
-          },
-          { singleton: true },
-        ),
+        input: createExtensionInput([stringDataRef], { singleton: true }),
       },
-      factory: ({ inputs }) => ({
-        text: `nest-${inputs.input.output.output}`,
-      }),
+      factory: ({ inputs }) => [
+        stringDataRef(`nest-${inputs.input.get(stringDataRef)}`),
+      ],
     });
 
     const tester = createExtensionTester(extension, {
diff --git a/packages/frontend-test-utils/src/app/renderInTestApp.tsx b/packages/frontend-test-utils/src/app/renderInTestApp.tsx
index dd03cdd2a2..b37a7c2a8d 100644
--- a/packages/frontend-test-utils/src/app/renderInTestApp.tsx
+++ b/packages/frontend-test-utils/src/app/renderInTestApp.tsx
@@ -152,14 +152,16 @@ export function renderInTestApp(
           kind: 'test-route',
           name: path,
           attachTo: { id: 'app/root', input: 'elements' },
-          output: {
-            element: coreExtensionData.reactElement,
-            path: coreExtensionData.routePath,
-            routeRef: coreExtensionData.routeRef,
-          },
-          factory() {
-            return { element: <React.Fragment />, path, routeRef };
-          },
+          output: [
+            coreExtensionData.reactElement,
+            coreExtensionData.routePath,
+            coreExtensionData.routeRef,
+          ],
+          factory: () => [
+            coreExtensionData.reactElement(<React.Fragment />),
+            coreExtensionData.routePath(path),
+            coreExtensionData.routeRef(routeRef),
+          ],
         }),
       );
     }