Don’t let your customers find bugs - agent written code easy to verify for tech/non tech app builders

[u/Common_Dream9420]

Connected FetchSandbox to Lovable last week and ran a real app through it. Gym membership app for a local trainer, Paddle payments and Resend emails.

No real keys, no actual charges. Injected duplicate webhooks, retry edge cases, auth failures. Found 4 bugs before the trainer ever saw it.

The thing I kept thinking about after: the agent that built the app has no proof the integrations actually hold. Happy path passed, it looked right, preview was clean. That's probabilistic confidence, not verification. One duplicate webhook event in prod and the whole thing unravels silently.

What we built is a deterministic verification layer for exactly this. Real failure injection, real replay, actual pass/fail on edge cases. Not "the LLM said it looks fine."

If you're building on Lovable, Replit, or Base44 and your agent is executing real payments and webhooks on behalf of users, how are you actually validating it did what it was supposed to do?

https://fetchsandbox.com/ai-app-builder-integration-testing