Skill: Testing Electric apps (unit + integration)

[KyleAMathews]

Context

Testing Electric apps requires different strategies for unit tests (mocked fetch) vs integration tests (real Electric server + Postgres). The integration test setup involves Docker, multiple services, and specific configuration.

Scope

Create an electric-testing skill covering:

1. Unit testing — Mocking fetchClient with vi.fn(), testing collection behavior without network
2. Integration test setup — Docker Compose for Postgres + Electric + nginx, port configuration
3. Building local Electric image — When to use canary vs local build
4. Test database management — Schema setup, teardown, test isolation
5. Testing patterns — Testing optimistic mutations, testing live query reactivity, testing error recovery
6. CI configuration — GitHub Actions / similar with Electric services

Source

Identified during domain discovery skill test run. Integration test setup is a distinct developer task with non-trivial infrastructure.