How we continuously validate formal specifications in production
Learn how Datadog built FETCh to continuously validate production behavior against TLA+ specifications and uncover a subtle bug that conventional testing had not exposed.
Quick read
This post describes FETCh, a system Datadog built to turn TLA+ specifications into runtime monitors that continuously validate production behavior against formal models. Someone would visit to learn how Datadog detected specification drift in their Husky event database and how FETCh uncovered a subtle bug missed by conventional testing.
- FETCh converts TLA+ specs into runtime monitors for production traces
- Detects mismatches between implementation and formal specifications
- Case study: uncovered a year-long routing placement bug in Husky
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