X Publishes 'For You' Feed Ranking Code Under Apache v2

X open-sourced its 'For You' feed ranking algorithm on GitHub under Apache v2 on August 13, 2026. The codebase is 10–15× larger than prior releases, adding model config, filter details, and ranking-signal weights. External researchers ran the ranker independently before launch. Developers may submit pull requests for X engineers to review. Grok-based rule-violation prediction systems are excluded.