RecalLC — Smart LeetCode Revision

Revise the LeetCode problems you already solved — RecalLC nudges you to review an older problem, at the moment you open a new one.

Solve it. Remember it. Master it. RecalLC is an open-source, local-first Chrome extension that helps software engineers and students retain LeetCode problem-solving patterns using spaced repetition (SM-2 algorithm) — right at the moment you open a new problem. When you open a problem like "Number of Islands", RecalLC automatically checks your revision queue and reminds you of older problems due for review (e.g., "Climbing Stairs was attempted 3 days ago and is due today"). ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 🌟 KEY FEATURES ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ • In-Page Revision Reminders: A clean, non-intrusive card appears on leetcode.com/problems/* when you have problems due for review. Options: Revise Now, Remind Tomorrow, or Dismiss. • Automatic Attempt Tracking: Recognizes when LeetCode displays an Accepted or Failed submission verdict and records your attempt history automatically. • Spaced Repetition Scheduling: Uses a proven spaced-repetition algorithm with customizable intervals (Forgot, Hard, Good, Easy or custom 1, 3, 5, 7 days). • Active Recall Flashcards: A dedicated recall mode with a 4-step thinking checklist and hidden notes to test your understanding before checking your past solutions. • Complete Local Dashboard: View due problems, overdue lists, revision streak, topic breakdowns, and search/filter across all tracked problems. • RFC-4180 Import & Export: Bulk import your past LeetCode attempts via CSV or JSON, and export your revision data anytime for full backup. • Optional Passcode Protection: Secure your dashboard with an optional master passcode hashed locally via SHA-256. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 🔒 100% PRIVATE & LOCAL-FIRST ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ • Zero external servers: Your data never leaves your device. • Zero telemetry or tracking: No Google Analytics, tracking pixels, or cookies. • Zero account required: RecalLC never asks for, reads, or touches your LeetCode password or session cookies. • 100% browser-local storage: All problem data and notes are stored strictly in IndexedDB and chrome.storage.local.