DEV3 Free Online Notepad and Paste Sharing — Source Code (Next.js + MongoDB)

Source code of the DEV3 Online Notepad and Paste Sharing, a paste-sharing tool with syntax highlighting, expiry from one hour to 30 days, burn after reading, optional scrypt-hashed password and abuse reporting.

Free download: sign in to any DEV3 account and click Download ZIP. Try it live: https://dev3.tech/tools/online-notepad-paste shows the finished tool running.

What is in the download

• Route handlers and pages for the Next.js App Router
• The service layer, Mongoose models and the UI components, in a dev3-tools/ folder that cannot clash with your own files
• README.md (install, environment, customise), .env.example and an MIT LICENSE

What the code does

• Dependency-free tokenizer for 12 languages rendered as React text
• Atomic burn-after-read
• Salted scrypt password hashing with guess limits
• noindex pages and admin moderation

Tech stack

Next.js 15 (App Router), React 19, TypeScript, Mongoose on MongoDB, Tailwind CSS 4.

Install and customise

The How to install and How to use tabs list the steps. In short: copy the module into a Next.js app, install the listed packages, add the MongoDB connection string and run it.

Good to know

• This is server code: you need a MongoDB database and your own hosting.
• Text is stored in plain form on the server (no client-side encryption).