API Contract Guard

What it does

A GitHub App that checks OpenAPI 3.x JSON or YAML contracts on every pull request and posts a native GitHub Check. It catches removed endpoints, responses, required inputs, and incompatible schema changes before merge—without adding a workflow file. Founding Starter offer: £1 for the first month, then £19/month.

Automated GitHub pull-request checks that block breaking OpenAPI changes before merge.

API Contract Guard installs as a GitHub App, compares OpenAPI specs on every pull request, and fails the check when an endpoint, response, parameter or schema breaks compatibility. Use a production specification as the baseline and the proposed version as the candidate. The automated GitHub App uses the same comparison engine. The free checker builds trust. The paid product runs continuously in GitHub with no manual review queue. A GitHub admin grants repository access through the GitHub App installation flow. Pull request events are queued and compared against the base branch OpenAPI contract. Breaking endpoints, required inputs, removed responses and schema changes fail the PR check. 5…from apicontractguard.com

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