AI-ready Engineering challenges

Solve Real Engineering Problems

Dear DSA, F*CK you respectfully!

Realistic repository based engineering problems. Real engineers will go beyond DSA.

Repo-based rounds are now asked at

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queue-processorDraft saved
QueueProcessor.java
12public boolean process(Message message) {
13  if (message.isExpired()) {
14    return false;
15  }
16  queue.publish(message);
17  return true;
18}

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  1. 01
    Read the codeLand in a real repo with a README brief.
  2. 02
    Make the changeFinish one small function in the editor.
  3. 03
    Tests confirmRun the unit tests and watch them pass.
01

Read the system

Start with a repository, a clear brief, and constraints that matter — the scoping skill AI still can't do for you.

02

Make the change

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03

Submit with intent

Track the outcome of each solution as the judging system evaluates it — and build judgment AI can't replace.

Your AI Sidekick

Use AI to solve real engineering problems

Your AI Sidekick works from the exact files you're editing, so you learn to harness AI on real code — asking questions, weighing trade-offs, and seeing how a fix comes together, at the level of assist you choose.

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AI SidekickAssist · Explore
Where should I start?
Open QueueProcessor.java and read the brief — the change belongs in process(). Every message should still get published.
Stuck? Switch me to Solve and I'll walk you through the fix.
  • ChillPoints you in the right direction, one hint at a time.
  • ExploreTalks through the trade-offs and how the system fits together.
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What's new

Latest updates

  • 10 new problems

    New

    Ten new repository-based engineering problems added to the catalog.

  • Roadmaps

    New

    A new roadmaps section to plan your path through real engineering skills.

  • Interactive demo

    New

    Explore the repo-shaped workspace right in your browser — no sign-up needed.

  • Results stay in the workspace

    New

    Run and submit without leaving the page — results open in a side drawer, keep grading in the background, and resume after a refresh, so you can keep editing and check the verdict at a glance.

  • Handbooks

    Core-concept reading material right inside the workspace, with diagrams rendered inline.

  • Run without submit

    Dry-run your solution through the judging pipeline without recording a submission.