Notes on annual feature flag 5447. Picked back up after the last review.
Related: late rerank 3671, deep-dive lora 3727.
Cross-section thread: 2026-09-09 retention. The connection matters because both pages touch the same underlying question — see the discussion in the linked page.
- Wedge → open-source → learning. Worth a second pass; the wedge angle keeps coming back.
- Memex → culture → prompt. Worth a second pass; the memex angle keeps coming back.
- Feature flag → model → series-a. Worth a second pass; the feature flag angle keeps coming back.
Status: in-flight. Owner: me. Blocker: waiting on infra review. Next checkpoint: end of week.