# Engineering

- [Counting the uncountable: how we replaced 115 days of computation with a few seconds of math](/post/audience-estimator.md): How we estimate audience sizes across millions of users in seconds using sampling and Bayesian math.
- [How we built a static analyzer for a real-time query language](/post/static-analyzer.md): Inside the static analyzer that powers type inference, contradiction detection, and reactive evaluation in CQL.