What is the best open-source alternative to Segment?

The best open-source alternative to Segment depends on the use case. The highest-PopScore candidates on GitPop are rudder-server, posthog.

Is Segment open source?

No, Segment is a closed-source product by Twilio, Inc.. The open-source alternatives on this page are listed by GitPop PopScore (momentum, activity, and noise-filtered).

2 candidates

Open source alternatives to Segment

Customer data platform for event collection, routing, and identity. · Twilio, Inc.

Pricing: Free up to 10k MTU; paid from $120/mo

Segment is the default CDP for SaaS teams. The open-source replacement in 2026 is RudderStack (warehouse-native CDP) and PostHog (analytics + feature flags). RudderStack is the most direct Segment replacement; PostHog is the right pick if you want CDP, analytics, and session replay in a single self-hosted product.

The 2 candidates, ranked by PopScore

#01rudderlabs/rudder-server
Warehouse-native customer data platform. The most direct Segment replacement in 2026, with self-hosting and a wide event-source catalog.
GitHub
#02PostHog/posthog
Open-source product OS with built-in event collection. The right pick when you want CDP, analytics, and feature flags in one product.
GitHub

Related alternatives

Looking for a side-by-side comparison of two open-source projects? The compare matrix has 60+ "X vs Y" pages. Looking for a curated "best of" list for a specific category? See Best AI tools 2026 (and the 7 other category editions).