Flashcards Review Platform

A fullstack flashcard application built around the spaced-repetition learning algorithm. Users can create decks, add cards, and review them on a schedule that adapts to their performance — surfacing harder cards more frequently and spacing out cards they know well.

The backend uses PostgreSQL to persist decks and review history, with an Express API handling authentication and scheduling logic. The frontend is a React SPA with smooth card-flip animations and a clean review interface.