Sasha Rush Departs Cursor After Releasing Composer 2 Technical Report
On Aug 25, Sasha Rush (@srushnlp), a well-known NLP researcher and former OpenAI employee, announced that it was his last day at AI coding tool company Cursor, corroborated by multiple independent sources (@eliebakouch, @twkillian, @vwxyzjn). His next destination was not disclosed.
Confirmed
- Sasha Rush officially announced his departure from Cursor on Aug 25, confirmed by multiple credible sources.
- Before leaving, he published a technical report on Composer 2 covering the full pipeline from model training and kernel design to inference optimization, and offered to answer technical questions (as relayed by @eliebakouch).
- He recounted that he originally just went for a coffee, received a keyboard that same afternoon, and began helping build Composer the next day, praising the team as fearless and ambitious.
- The same day, Eric Mitchell (@ericmitchellai) posted that it was also his last day at Cursor, using a nearly identical narrative of coffee, an afternoon keyboard, and joining Composer work.
Unconfirmed
- Eric Mitchell's post mirrors Sasha Rush's farewell post almost verbatim, including the coffee-and-keyboard detail, so it could be an inside joke or parody; his actual departure needs further confirmation.
- Sasha Rush's next destination remains undisclosed.
Why it matters
Composer is one of Cursor's core model capabilities, and Rush's involvement from day two shows how directly senior research talent shaped the product. Publishing Composer 2 training and kernel design details at his departure offers a rare inside view into the star AI coding company's technical roadmap; consecutive departures of core researchers may also raise questions about the stability of Cursor's research team.
2026-08-25 ~ 2026-08-26 · 6 related posts
Primary sources
- Veteran member departs AI coding tool company Cursor — srush_nlp ·
- Exiting Cursor Engineer Details Composer 2 Training and Kernel Design — eliebakouch ·
- [source] Veteran member departs AI coding tool company Cursor — srush_nlp · 2026-08-25
- [source] Exiting Cursor Engineer Details Composer 2 Training and Kernel Design — eliebakouch · 2026-08-25
- NLP Expert Sasha Rush Leaves AI Coding Tool Company Cursor — srush_nlp · 2026-08-25
- Eric Mitchell leaves Cursor after working on Composer — ericmitchellai · 2026-08-25
- Sasha Rush's last day at Cursor — vwxyzjn · 2026-08-26
1 near-duplicate retellings: tw_killian