PostHog
Product usage → features. Aggregate only — no per-user data, no PII.
How it works
Page views and URL-tagged events map to features via the same route
extractors that build the feature map. One env var enables it: NEXT_PUBLIC_POSTHOG_APP_VERSION=$VERCEL_GIT_COMMIT_SHA, so events join to the scan from the right commit.
Metrics it powers
get_feature_pageviews— traffic and usage per feature (MCP tool)- Traffic share per feature
events_14d— 14-day event count per feature- “Used by X% of users” context for prioritising what to fix