PRIVATE BETA — WAITLIST OPEN

Remember every problem you solve.

Pebble is a daily practice room for data structures and algorithms. You pick the hour; it brings back the right problems at the right time and asks you to explain the ones you already know.

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◍ built on SM-2◍ Feynman reviews◍ no streak gimmicks
Tuesday · your hour 19:00 – 20:00
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composed from your last 14 sessions open the app tour →
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HOW IT WORKS

One loop, four steps.

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EXPLAIN-BACK

Re-solve it in words, not boilerplate.

Re-coding a problem you already solved burns most of the hour on typing. Pebble asks you to say the approach instead — the invariant, the edge cases, the complexity. Five minutes of articulation beats forty of re-implementation.

TRANSCRIPT · 42s "One half is always sorted at the midpoint, so I check which half that is, then decide whether the target can be inside it."
MASTERY MAP

See what you'd actually recall today.

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no streaks · no vanity counters
WHO IT'S FOR

If you've forgotten a problem you once solved, this is for you.

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Start with tomorrow's hour.

Join the waitlist and we'll open your seat with a ten-minute calibration. Your first session is built from it.

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