LO
DeploymentCognitive automation2025-04-22
Uber says its LLM-based tool produced fixes for 224 of 404 data races in its Go codebase over 18 months, and developers accepted 193 of them in code review
Backend developeroccupation page →
Event date / reported
2025-04-22
Evidence stage
DeploymentAn employer has put it into production. Can move the baseline — weighted by scale and how similar the setting is.
Tasks this bears on
Keeping it correct when things happen at once
Transactions, idempotency, retries, ordering — deciding what must never be true and making sure it never is.
Still human-led✓ Evidence-backed
Where this applies
A peer-reviewed paper by Uber engineers about a tool running in Uber's own developer workflow. Over 18 months it identified 404 reproducible data races in Uber's Go codebase, produced fixes for 224 (55%), and developers approved 193 of those (86%) in code review; rejected fixes included ones judged incorrect despite passing initial tests. Uber does not sell the tool. It covers low-level data races in one language and one codebase, not transactions, idempotency, retries or ordering across services, and every fix went through a person's review.
What this means
Part of the concurrency work — fixing low-level data races once they are found — is now being drafted by a tool at one large company, with code owners deciding what goes in. The harder part, deciding what must never be true across services, is not what it does.
What it does not yet show
One company's tool on one language's data races; it does not show fewer engineers on concurrency or anything about distributed transactions.
What you can check
Open arXiv:2504.15637 (Dr.Fix) and find "193 of these patches (86%) were accepted by more than a hundred developers via code reviews".
Does it change the assessment?
No. The impact index is never moved by a single event. What this record did: the 1 linked task judgement above now rest on evidence instead of inference.
Source
Uber — "Dr.Fix: Automatically Fixing Data Races at Industry Scale", arXiv:2504.15637 (22 April 2025; published at PLDI 2025) · verified 2026-09-27 · Claude (VOLO agent) · interpreted 2026-09-27 · Claude (VOLO agent)
Primary source — published by the party that did this, or the authority of record. No co-signature needed.