A simple text and file sharing app, built on Next.js 16, Turso (libSQL), and Vercel Blob.
How it works
- Paste text or upload a file on the home page, optionally pick a custom link name and an expiry, and get a shareable
/s/<id> link.
- Text content and all share metadata (filename, size, expiry, download count) live in Turso.
- File bytes upload directly from the browser to Vercel Blob storage (
app/api/blob-upload/route.ts only issues a short-lived upload token; it never sees the file bytes). Turso stores a reference (URL + pathname) to the blob, not the file itself.
- Links expire automatically: once a share is read after its
expires_at has passed, the Turso row and its Blob file (if any) are deleted.
- Downloads hit
app/api/files/[id]/route.ts, which checks the optional access code, then 307-redirects to the blob's downloadUrl — a URL Vercel Blob generates that forces Content-Disposition: attachment with the original filename. File bytes never pass through your serverless function on upload or download.
- Shares can optionally require an access code to view/download, and can use a custom link name instead of a random id.
- Each share page shows a QR code linking to it.
- Live shares are a third mode alongside Text and File: an editable, two-way-syncing text pad. Anyone with the link can edit it, and edits propagate to everyone else viewing within ~2 seconds (
app/api/live/[id]/route.ts — the client debounces saves ~600ms after typing stops and polls for remote changes every ~2s, skipping the merge while the viewer's textarea is focused so it doesn't clobber what they're mid-typing). Use this instead of a Text share when you need to keep updating the same link rather than creating a new one each time.
One-time setup: create a Vercel Blob store
You need a BLOB_READ_WRITE_TOKEN. Easiest path with the Vercel CLI (already installed on this machine):
vercel login # interactive — opens a browser
vercel link # links this folder to a Vercel project
vercel blob store add # creates a Blob store, follow the prompt to name it
vercel env pull .env.local # pulls BLOB_READ_WRITE_TOKEN (and other linked env vars) into .env.local
Alternatively, in the Vercel dashboard: Storage → Create Database → Blob, then copy the BLOB_READ_WRITE_TOKEN from the store's .env.local tab.
Local development
-
Copy .env.example to .env.local (if you didn't use vercel env pull above) and fill in:
TURSO_DATABASE_URL=libsql://your-database.turso.io
TURSO_AUTH_TOKEN=your-turso-auth-token
BLOB_READ_WRITE_TOKEN=your-vercel-blob-read-write-token
MAX_UPLOAD_MB=1024
-
Install dependencies and run the dev server:
npm install
npm run dev
The shares table is created automatically on first use — no manual migration step needed.
Upload size limit
MAX_UPLOAD_MB caps how large a shared file can be (default 1024 MB / 1 GB). Because uploads go directly from the browser to Vercel Blob using client uploads with multipart enabled, this is a Blob-enforced limit, not a Vercel serverless request-body limit — raise it freely (Vercel Blob supports up to 5 TB per file). The practical ceiling is your Vercel plan's storage/bandwidth allowance and how long you're willing to let a browser upload run.
Deploying to Vercel
- Push this repo to GitHub/GitLab/Bitbucket and import it in Vercel (or just run
vercel deploy after vercel link, done above).
- If you created the Blob store via the CLI above,
BLOB_READ_WRITE_TOKEN is already attached to the project. Otherwise, add these in the project's Environment Variables settings:
TURSO_DATABASE_URLTURSO_AUTH_TOKENBLOB_READ_WRITE_TOKENMAX_UPLOAD_MB (optional, defaults to 1024)
- Deploy. No other configuration is required.
Tech
- Next.js 16 (App Router, Server Actions, Route Handlers)
@libsql/client for Turso (metadata + text content)@vercel/blob for file storage- Tailwind CSS
