fix: allow API base URL override

README.md

@@ -133,7 +133,11 @@ npm install
 npm run dev
 ```
 
-The app runs against the live testnet API by default.
+The app runs against the live testnet API by default. To use a different backend, set `VITE_API_BASE_URL`:
+
+```bash
+VITE_API_BASE_URL=http://localhost:3000/api/v1 npm run dev
+```
 
 No local backend setup is required to start contributing to the frontend.
 

src/constants/config.test.ts

@@ -0,0 +1,30 @@
+import { afterEach, describe, expect, it, vi } from 'vitest'
+
+const DEFAULT_API_BASE_URL = 'https://stepfi-api.onrender.com/api/v1'
+
+async function importConfig() {
+  vi.resetModules()
+  return import('./config')
+}
+
+describe('config', () => {
+  afterEach(() => {
+    vi.unstubAllEnvs()
+  })
+
+  it('uses the live testnet API by default', async () => {
+    vi.stubEnv('VITE_API_BASE_URL', undefined)
+
+    const { API_BASE_URL } = await importConfig()
+
+    expect(API_BASE_URL).toBe(DEFAULT_API_BASE_URL)
+  })
+
+  it('uses VITE_API_BASE_URL when provided', async () => {
+    vi.stubEnv('VITE_API_BASE_URL', 'http://localhost:3000/api/v1')
+
+    const { API_BASE_URL } = await importConfig()
+
+    expect(API_BASE_URL).toBe('http://localhost:3000/api/v1')
+  })
+})

src/constants/config.ts

@@ -1,5 +1,5 @@
 export const API_BASE_URL =
-  'https://stepfi-api.onrender.com/api/v1'
+  import.meta.env.VITE_API_BASE_URL ?? 'https://stepfi-api.onrender.com/api/v1'
 
 export const STELLAR_NETWORK = 'TESTNET'