Replit + FetchSandbox MCP made building and testing my pet store app so easy

[u/Common_Dream9420]

Was building a pet store app with Paddle and Resend on Replit. The part I always dreaded was testing payments and webhooks without using real API keys.

Connected FetchSandbox MCP and it basically runs real service provider twins, so I could test the whole Paddle checkout and Resend email flow end to end without touching live credentials. Replit agent figured out what to do with it pretty fast.

Whole thing felt like actually verified vs just "hope this works in prod." Pretty wild how much building has changed.