LeetDeeper

Different companies test different things. Some focus on algorithms and data structures. Others, especially infrastructure and AI teams, want to see you reason about concurrency limits, async execution ordering, error propagation, backoff and retry behavior, and runtime tradeoffs under real constraints. The infrastructure primitives we all use, but rarely implement.

I built LeetDeeper to practice that second category. You re-implement the building blocks of modern systems: Promise.all, concurrency limiters, async queues, retry with backoff. You get a browser editor and a test suite. No scaffolding, no abstract puzzles, just you and the edge cases.

AI-generated code often looks correct while hiding subtle execution bugs. If you’ve never built these primitives yourself, you’re less likely to catch those issues in review. LeetDeeper is a way to build that muscle.