Rqlite is a lightweight, open-source, distributed relational database built on SQLite and Raft, emphasizing reliability and quality. Despite its robustness, there have been fewer than 10 instances of panics in production, a testament to its disciplined testing strategy. The testing approach follows the well-known testing pyramid, prioritizing unit tests as the foundation, integration tests, and minimal end-to-end tests. The testing process covers various layers, including unit testing, system-level testing, end-to-end testing, and performance testing. Lessons learned from testing rqlite emphasize starting small, reacting to test failures, maximizing determinism, being deliberate, adapting and iterating, and prioritizing efficiency to maintain high quality.
https://philipotoole.com/how-is-rqlite-tested/