FlyppBook

Upload a PDF, note the client, and get a polished, trackable online flip book plus a one-click "Copy for Gmail" share block. Built to run on free tiers.

Multi-user: each account sees only its own books, share links and activity. A superuser (bootstrapped from env vars) manages accounts and sees usage analytics across everyone.

How it works

• Upload (admin): the PDF is rendered to per-page WebP images in your browser (pdf.js). The original PDF is never uploaded or hosted, so there's nothing straightforward for a client to download.
• Storage: page images live in Vercel Blob; book metadata + analytics in Neon Postgres. Page images are streamed to viewers through /api/book/<slug>/page/<n>, so the real storage URLs are never exposed.
• Viewer (/b/<slug>): a real page-curl flip book (page-flip) — two-page spread on desktop, single page on mobile.
• Sharing: the admin book page renders a book-styled email thumbnail and a Copy for Gmail button that puts a clickable image + link on your clipboard. (Email clients strip JS/iframes, so the live flip can't run inside the email — the image links out to the full experience. This is the richest thing Gmail keeps.)
• Analytics: every view and the deepest page reached is recorded per visitor; see it on each book's page.

Tech

Next.js 16 (App Router) · Neon Postgres · Vercel Blob · pdf.js · page-flip · jose.

Local development

1. cp .env.example .env.local and fill in the required values (including the SUPERUSER_* credentials you'll first sign in with).
2. (Optional) node --env-file=.env.local scripts/init-db.mjs to create tables up front — the app also creates them lazily on first use.
3. npm run dev → http://localhost:3000

Deploy to Vercel (free)

1. Neon: Vercel dashboard → Storage → create a Neon Postgres store. Copy the pooled connection string into DATABASE_URL.
2. Blob: Vercel dashboard → Storage → create a Blob store (auto-wires BLOB_READ_WRITE_TOKEN in the project).
3. Env vars: set SESSION_SECRET (openssl rand -base64 32), SUPERUSER_USERNAME / SUPERUSER_PASSWORD / SUPERUSER_EMAIL, and (optionally) RESEND_API_KEY / RESEND_FROM for password-reset emails, in Project → Settings → Environment Variables.
4. Push the repo and import it in Vercel, or run vercel --prod.

Cost at ~300 PDFs/year

Comfortably within free tiers. ~300 books × ~20 pages × ~120 KB ≈ ~700 MB of Blob (free tier is 1 GB+), Neon rows are tiny, and traffic is low. Expected: $0.

Environment variables

Variable	Required	Purpose
DATABASE_URL	✅	Postgres connection string (Supabase/Neon/local)
BLOB_READ_WRITE_TOKEN	✅	Vercel Blob (auto on Vercel)
SESSION_SECRET	✅	Signs session cookie + hashes visitor IPs
SUPERUSER_USERNAME	✅	Superuser login (manages all accounts)
SUPERUSER_PASSWORD	✅	Superuser password (env is source of truth)
SUPERUSER_EMAIL	—	Superuser email (for password resets)
RESEND_API_KEY	—	Resend key for reset emails (else logged to console)
RESEND_FROM	—	From address for reset emails
NEXT_PUBLIC_BASE_URL	—	Override share-/reset-link origin

Notes on "not downloadable"

This is deliberately light protection, per the brief: no raw PDF is ever served; images are proxied (real Blob URLs hidden); right-click and image drag are disabled in the viewer. A determined user can still screenshot — that's fine.