VocabMaster is a feature-rich vocabulary learning application built with a modern full-stack architecture. It uses a **spaced repetition system (SRS)** with three progressive review phases — Daily, Weekly, and Monthly — to optimize long-term word retention. Users can add words with meanings, example sentences, descriptions, and parts of speech, then quiz themselves through multiple-choice questions generated from their own vocabulary collection. The smart revision engine tracks correct/wrong answers, auto-advances words through phases, and even removes words that consistently get wrong answers. The app features Google OAuth authentication, a Turborepo monorepo structure, type-safe API communication via Elysia Eden, and a polished responsive UI with dark mode support.