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Onsite simulator

Stop guessing. Start performing.

The only simulator that identifies your specific technical failure modes and assigns the high-repetition drills needed to fix them.

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LoopCoach workspace screenshotLoopCoach workspace screenshot
Built for Tier-1 onsite dynamics: time pressure, follow-ups, and the social part of being “correct”.
Failure modesAssigned drillsTimed rounds
Two modes

Different psychological load

Coach optimizes for learning. Interviewer optimizes for proof under pressure. Same question, different rules: what’s allowed, what’s challenged, and what must be defended.

Coach Mode (Safety Net)
Nudges constraints. Keeps reps productive.
system
MODE: Coach. Goal: unblock learning. Ask for constraints before code.
user
I think I can use a heap to keep the top-k.
ai
You’ve missed a constraint on duplicate inputs; how does that change your approach?
Interviewer Mode (Stress Test)
Targets weak claims. Forces proof + tradeoffs.
system
MODE: Interviewer. Goal: pressure-test claims. Demand proof + tradeoffs.
user
I can do it in O(n).
ai
The solution is O(n log n). Prove it can’t be done in O(n).
Next: what gets detected after the round.See the diagnostic report
The feedback loop

Technical diagnostic report

Not vibes. Not generic advice. Failure modes detected → drills assigned.

Failure Modes Detected
Example excerpt
  • Constraint leakage
    Missed duplicates constraint → invalidates invariant.
  • Optimization cargo-culting
    Reached for heap without proving it’s needed.
  • Edge-case coverage
    Didn’t enumerate boundary inputs before committing.
Leakage Points
Edge Case Coverage
42%
Boundary inputs not enumerated early.
Inference Accuracy
57%
Claims need sharper proofs under pressure.
Tradeoff Clarity
38%
Alternatives not compared out loud.
Next drills (assigned)
Failure mode → drill
  • Constraint leakage → Write constraints first, then restate invariant under the new constraint.
  • Weakness in heap-based optimizations → Compare heap vs sort vs two-pointer and justify with big‑O + constants.
If you want fewer surprises in the room, run the loop.Jump to start
The hard truths

What this is (and isn’t)

Engineering-first answers. No marketing fog.

Is this just LeetCode with a chatbot?
LeetCode teaches you to solve puzzles. LoopCoach teaches you to navigate the 45-minute social and technical pressure of a Tier-1 onsite — clarifying questions, defending tradeoffs, handling follow-ups, and staying coherent while the room pushes back.
What’s the difference between Coach and Interviewer?
Coach is supportive and keeps you moving. Interviewer is stricter and pressures your claims with probing follow-ups.
What data do you store? Can I delete sessions?
Your session history is yours to review — and deletable. You control what you keep.
If you want to test performance, don’t read — run it.Jump to start
Ready?

Run one loop. Get your failure modes.

Then fix them with assigned drills. Repeat until they stop showing up.

  • Timeboxed rounds with follow-ups
  • Rubric scorecard + debrief notes
  • A concrete plan for the next reps

No credit card. Takes ~60 seconds to start.

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