lemma: Comp Math Trainer

Train like a quant. Daily.

Lemma is the focused, no-fluff prep app for quantitative interviews — built for students and grads targeting Jane Street, Citadel, Optiver, Two Sigma, and the rest of the trading-firm gauntlet.

WHAT'S INSIDE WITH YOUR SUBSCRIPTION

• Daily sprints — bite-sized timed sets of mental math, probability, combinatorics, expected value, and market-making problems
• Per-category ELO — your skill is tracked across 10 disciplines, from Novice to Expert
• Adaptive difficulty — problems chosen to keep you at the edge of your level, not above or below
• Hints + step-through solutions — get unstuck without giving up
• Streaks, XP, leagues — habit loops without the noise
• Achievements — unlock as you grind
• Leaderboard — see how you stack up

WHO IT'S FOR

• CS / math undergrads applying to trading firms
• Recent grads prepping for technical interviews
• Self-learners who want a daily quantitative-thinking habit
• Anyone curious about how trading interviews actually feel

WHY LEMMA

We strip out the gamified clutter and keep what matters: hard problems, fast iteration, real numbers on your progress. The interface borrows more from a Bloomberg terminal than a typical mobile game — monospaced metrics, hairline borders, dark by default.

Most prep books drown you in 800 pages. Most courses lock you in for months. Lemma is 10 minutes a day, sharpened every day.

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Lemma offers an optional auto-renewable subscription for unlimited daily sprints and premium problem sets. Subscriptions auto-renew unless cancelled at least 24 hours before the end of the current period. Manage or cancel anytime in your Apple ID settings.

Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Privacy Policy: https://rogeru13.github.io/lemma-legal/privacy-policy/