WorkedCoding
Migrate int32 IDs to int64 across a giant codebase
Tools: Google internal LLM migration tooling
Setup, access, approval gate, failure notes
- Setup / prompt
- Locate references, have the LLM propose edits, validate with builds/tests, route to owners for review.
- Access required
- Monorepo change generation; standard code review
- HITL checkpoint
- Every change human-reviewed; many edited before submit
- Outcome & failure notes
- LLMs generated ~74% of the 595 submitted changes (~69% of edits); ~38% needed human edits and ~26% were human-only. Developers estimated ~50% less migration time. Not a 'set and forget' win.
- Evidence type
- Peer-style paper (company-reported)
Source: arXiv: Migrating Code At Scale With LLMs At Google · 2025-04 · Checked 2026-10-19