Full-Stack SaaS
Flashy
Full-stack study SaaS built with Next.js 14, Clerk, Firebase Firestore, Stripe, and OpenRouter — six study modes, AI card generation, classes, and Free/Basic/Pro subscriptions.
Overview
Flashy is a full-stack study platform for building flashcard decks and drilling them until they stick. Create sets from notes or by hand, organize them in folders, share public links, join classes, and track streaks and daily goals. AI generates cards from pasted notes, coaches wrong answers, and builds exam study plans. Study modes include Due Today (spaced review), Flashcards, Learn, Write, Match, and Test — all keyboard-friendly. Free, Basic, and Pro plans unlock more decks and daily AI actions.
On the engineering side, Flashy is a Next.js 14 App Router app with API routes for AI, Stripe checkout, billing webhooks, and Firebase token minting. Clerk handles auth and protected routes; Firebase Admin issues custom tokens so the client reads and writes Firestore under security rules. Stripe powers Basic/Pro subscriptions and the customer portal. OpenRouter runs server-side AI (generate, explain, expand, coach, difficulty tags, study plans) so users never bring their own API key. Tailwind CSS and next/font (Syne + Figtree) cover light/dark UI; Vercel hosts production.