This repo contains a version of Anthropic's original performance take-home, before Claude Opus 4.5 started doing better than humans given only 2 hours.

Now you can try to beat Claude Opus 4.5 given unlimited time!

measured in clock cycles from the simulated machine:

• 2164 cycles: Claude Opus 4 after many hours in the test-time compute harness
• 1790 cycles: Claude Opus 4.5 in a casual Claude Code session, approximately matching the best human performance in 2 hours
• 1579 cycles: Claude Opus 4.5 after 2 hours in our test-time compute harness
• 1548 cycles: Claude Sonnet 4.5 after many more than 2 hours of test-time compute
• 1487 cycles: Claude Opus 4.5 after 11.5 hours in the harness
• 1363 cycles: Claude Opus 4.5 in an improved test time compute harness

If you optimize below 1487 cycles, beating Claude Opus 4.5's best performance at launch, email us at [email protected] with your code (and ideally a resume) so we can be appropriately impressed and perhaps discuss interviewing.

Run python tests/submission_tests.py to see which thresholds you pass.