X algorithm release changelog
Tracks public drops of github.com/xai-org/x-algorithm. xAI stated intent to publish updates ~every 4 weeks; commits are squashed ('CI agent'), so diffs between drops ARE the news. This page updates with each drop. Last checked 2026-07-31,
HEAD 0bfc279.
2026-07-15 — Musk pledges full X codebase open-sourcing with third-party verification announced
Announcement only (following the Grok build exfiltration incident): the entire X codebase to be open-sourced with third-party verification that production matches GitHub. Not yet delivered as of Jul 31. If it ships, the withheld params (the actual weights) may become public — we will publish them the day they do.
2026-05-15 — Runnable Phoenix pipeline + mini checkpoint (~2.9 GB) shipped
phoenix/run_pipeline.py end-to-end retrieval→ranking demo; downloadable mini-Phoenix checkpoint via Git LFS (128-dim, 4 layers, ~1.4 GB embedding tables, 537K-post sports demo corpus). 19 binary action heads + continuous dwell/watch/scroll heads confirmed in runners.py. Weights in the demo script (fav 1.0 / reply 0.5 / repost 0.3 / dwell 0.2) are illustrative, NOT production.
2026-01-20 — Grok-era stack open-sourced: Phoenix / Thunder / Home-Mixer / Grox shipped
Apache 2.0 release replacing the 2023 repo as the current reference: Rust home-mixer (scorers + 17 filters), Thunder in-network store, JAX Phoenix ranker (Grok-1 architecture port), Grox LLM content classifiers (prompts withheld). All weight constants read from an unpublished params module. Rust crates ship without Cargo.toml — reference code, not buildable.
2023-03-31 — Legacy: twitter/the-algorithm (frozen) frozen
The 2023 open-sourcing with the famous heavy-ranker weights (reply 13.5, like 0.5, retweet 1.0, profile click 12, report −369). Frozen at commit c54bec0; superseded by the 2026 stack. Still the only public weight values that ever existed — every '2026 exact weights' article is recycling these.