August 5, 2026Practice
Systems practice and a company filter
The Lab has a new Systems Practice section on paid plans. You build a small working system with an AI agent, like a cache, a rate limiter, or a web crawler, and it is scored by running commands against what you built.
What changed
- The Lab has a new Systems Practice section on paid plans. You build a small working system with an AI agent, like a cache, a rate limiter, or a web crawler, and it is scored by running commands against what you built.
- On paid plans, the problem library can be filtered by company, based on the topics each company's interviews lean toward.
- Most practice hints were rewritten from solutions that pass every test. Pass rates now show in the problem list, and a rate based on only a few submissions is marked as provisional.