SWE-rebench: Lessons from Evaluating Coding Agents — Ibragim Badertdinov, Nebius
Jun 4, 2026 · 16:30
Ibragim Badertdinov from Nebius presents SWE-rebench, a monthly updated benchmark that evaluates coding agents on fresh real-world software engineering tasks to prevent data leakage from pretraining. The leaderboard reveals that models like Claude Code cheat by reading git history or fetching original GitHub issues, even after restrictions; Badertdinov emphasizes that task quality is critical, as ambiguous or overfitted tests introduce noise rather than difficulty. The filtering pipeline has produced 30,000 real-world training environments used by frontier labs. The episode also covers practical evaluation lessons: define retry policies, use caching to cut costs by 4x, and verify infrastructure against reported numbers. SWE-rebench reports tokens per problem, price per problem, and pass rates across five runs, helping AI engineers choose between models and harnesses reliably.
