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Dev tools · April 28, 2026

TraceCode

Learn algorithms by watching them run

What it does

Grinding LeetCode teaches you to pattern-match memorized solutions, not to actually see how algorithms work. TraceCode is different, you step through real code, watch state change live, and do drills that make you predict what happens next. Fewer problems, deeper understanding, better interviews.

Does the same job

all alternatives →
  • IM
    I made a spaced repetition tool to master coding problems2024 · lanki.xyz · ▲206

    As you solve LeetCode questions, you can mark them as hard, medium, or easy. The tool will then recommend questions you should review based on (1) how hard the question was for you and (2) how much time has passed since you last reviewed it. I'd recommend normally attempting LeetCode problems and just marking them as hard, medium, or easy for you at first so the tool knows which problems to recommend you review! Here's the theory behind spaced repetition and learning if interested: https://www.codecademy.com/article/spaced-repetition

  • CA
    CodeRev.app – Code Review as Interview2024 · coderev.app · ▲150

    I've long had a dislike for leetcode interviews on both sides of the coin. Project-based interviews can also be challenging because it can end up filtering out folks who don't want to spend several hours building something in their free time. I met up with a friend last year -- a very senior dev -- who had taken some time off to study leetcode exercises while preparing for FAANG interviews. It struck me that one of the key measures of whether a candidate is a fit for a team is rather synthetic. CodeRev.app is a simple, lightweight tool that helps teams evaluate candidates using code reviews.…

  • LeetCard: Coding FlashCards2024 · ▲134

    Your best LeetCode companion

  • Openleetcode – Local LeetCode runner where tests live in the repo19d ago · github.com · ▲73

    You write a standard solution, just like on LeetCode, and run it through the CLI. It identifies the problem by ID or title, executes your code against local test cases, and shows the result. It currently supports around 1.4k problems and multiple languages, including Python, C++, Rust, Java, Go, TypeScript, Swift, and others. The project is still an MVP. System design, SQL, and concurrency problems are not supported yet, but support for more problem types is planned. Made in Haskell!

  • SolveFaction2020 · ▲77

    Short mobile LeetCode-like challenges in game-like app

  • LeetCode CoachJun 2026 · leetcodecoach.vercel.app · ▲4

    AI mentor that tells you exactly what to solve next

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