PostHog describes using parallel Claude Code sessions, property-based testing, and production shadow mode to replace its ANTLR-based SQL parser with a hand-rolled parser, illustrating a controlled AI-assisted workflow for a large open-source analytics codebase.
I wrote a 70x faster SQL parser while barely looking at the code
PostHog describes using parallel Claude Code sessions, property-based testing, and production shadow mode to replace its ANTLR-based SQL parser with a hand-rolled parser, illustrating a controlled AI-assisted workflow for a large open-source analytics codebase.
Source: Posthog