A little space
for a careful change.

The reason for the desk

API clients show you what a service does today. DiffHaven starts one step earlier: comparing the contracts between releases, before you make a request.

The idea is not to replace your validator, tests or judgment. It's to give structural changes a visible place in the review, with traceable evidence and practical next steps.

Independent, and early.

An independent project by Hưng, a student developer in Vietnam. DiffHaven is a standalone prototype, not an incorporated-company claim or an established commercial service.

There are no accounts, paid plans, customer endorsements or production-usage claims. The fictional parcel API is sample data, not a customer integration.

Local is a product decision.

Your contracts stay in the browser. No uploads, third-party scripts, analytics, external fonts or declared-endpoint requests. Deterministic rules keep findings reproducible and their evidence inspectable, without handing the contract to a remote analysis or model service.

What comes next?

Better coverage, regression fixtures and clearer reviews are the direction. No AI integration is planned for the product. Claude Code was used for development assistance on 2026-10-08 to expand string-length and array-size checks and add regression tests. Changes were independently reviewed and tested. It is not customer-facing analysis. The review remains deterministic and transparent about its limits.

Project contact

Project domain: diffhaven.com. Questions or feedback: founder@diffhaven.com.