I built this after breaking production APIs one too many times.
The problem was always the same: remove or change an endpoint, deploy, and a few hours later customers email saying their integrations broke.
API Impact Tracker answers one simple question before deploy:
"Which real clients will break if I ship this?"
It works by tracking which clients use which endpoints (via middleware),
normalizing paths (e.g. /users/123 → /users/{id}),
and comparing real usage with your OpenAPI spec.
Design choices:
- Runs locally (SQLite) – no data leaves your infrastructure
- No SaaS, no phone-home
- Open source (MIT)
- CLI + GitHub Action
- Takes ~5 minutes to set up on an existing Express API
I'd love feedback, especially on:
1) API versioning and deprecations
2) GraphQL support
3) Other API-change pain points you've seen
Thanks!
mickle00•3w ago
why not just version API for breaking changes?
PeterDS•3w ago
Great question. Versioning definitely helps, and most teams do version their APIs.
The problem I kept running into is that versioning answers “where do we put breaking changes?” but not “who is still using this?”
PeterDS•3w ago
I built this after breaking production APIs one too many times.
The problem was always the same: remove or change an endpoint, deploy, and a few hours later customers email saying their integrations broke.
API Impact Tracker answers one simple question before deploy: "Which real clients will break if I ship this?"
It works by tracking which clients use which endpoints (via middleware), normalizing paths (e.g. /users/123 → /users/{id}), and comparing real usage with your OpenAPI spec.
Example output:
$ api-impact diff openapi.yaml
DELETE /users/{id}Clients affected: - acme-inc (used 2h ago) - foo-app (used yesterday)
Design choices: - Runs locally (SQLite) – no data leaves your infrastructure - No SaaS, no phone-home - Open source (MIT) - CLI + GitHub Action - Takes ~5 minutes to set up on an existing Express API
I'd love feedback, especially on: 1) API versioning and deprecations 2) GraphQL support 3) Other API-change pain points you've seen
Thanks!