What problem does it solve? Unit tests with mocked dependencies miss bugs in real database queries, HTTP middleware wiring, serialization, and service-to-service contracts. This Skill provides patterns for testing components against real infrastructure so integration bugs surface before production. ## Core Features & Use Cases - Testcontainers Database Testing: Spin up real Postgres, MySQL, Redis, or Kafka containers per test suite in Python, TypeScript, or Go, with transaction-rollback isolation and schema migrations run before the suite. - HTTP API and Contract Testing: Exercise full request/response cycles with TestClient, supertest, or httptest, and verify cross-service agreements with consumer-driven Pact contracts. - Message Queue and Test Data Management: Test event producers and consumers, build fixture factories, and apply cleanup strategies like transaction rollback and per-worker schema isolation. - Use Case: A team adding a new orders endpoint uses Testcontainers to run tests against a real Postgres instance, writes supertest lifecycle tests for the API, and publishes a Pact contract so the consuming billing service can verify compatibility independently. ## Quick Start Ask the AI to set up integration tests for your service using Testcontainers with a real Postgres database and transaction rollback per test.
