Jitsu is an open-source Segment alternative with event collection and API connectors. It can stream and collect the data to any data warehouse of your choice and can be deployed in 2 minutes.
Looking beyond Jitsu for data collection and routing? Try PostHog for self-hosted product analytics, Segment to unify customer events across tools, Amplitude for deep growth insights, and Plausible Analytics for privacy-friendly, lightweight web stats.