Live Developer Tool
API Contract Firewall
Contract testing without writing contracts.
What it is
A Cloudflare Worker forward proxy that watches your API traffic, learns the JSON schemas your endpoints actually return, and blocks deploys that would break them.
The problem
APIs break silently. Someone renames a field, a type drifts, latency creeps up, and the frontend finds out in production. Hand-written contracts rot because nobody maintains them.
How it works
-
Point your API through the worker proxy.
-
It learns request and response schemas from real traffic, no contract files needed.
-
Schema drift, breaking changes, and latency regressions are flagged on a dashboard.
-
A CI gate blocks the deploy when a change would break consumers.
Features
- Learning proxy
- Schemas are inferred from live traffic, including a learning mode per endpoint.
- Drift detection
- Breaking changes and schema drift surface before they ship.
- Latency watch
- P95 regressions are tracked alongside correctness.
Stack
- Cloudflare Workers
- Next.js
- Supabase Postgres
- Vercel