Gleam: Type-safe language built upon the BEAM
Web: Wisp framework + Mist HTTP server
Frontend: Lustre for HTML rendering
Storage: In-memory only (no persistence)
Security: AES-256-GCM client-side encryption, CSRF tokens, rate limiting, security headers

Configuration

SECRET_KEY_BASE (Required for Production)

The application uses a secret key base for signing cookies and security tokens.

You must set this for production deployments to ensure security and session persistence across restarts.

# Generate a secure key (48 bytes of random data)
export SECRET_KEY_BASE=$(openssl rand -base64 48)

# Or set it manually
export SECRET_KEY_BASE="your-secret-key-here"

⚠️ Warning: If not set, a temporary key will be generated on each startup. This:

Invalidates all existing user sessions/cookies after restart
Reduces security (new key generated each time)
Generates a warning in the logs

For development, you can use:

SECRET_KEY_BASE=dev gleam run

Quick Start

# Clone and build
git clone https://git.kharec.info/Kharec/spasteg.git
cd spasteg
gleam run

The server starts on http://localhost:3000.

Docker image+deployment

Build

docker build -t spasteg .

Run

# Generate a secure key
docker run -p 3000:3000 -e SECRET_KEY_BASE=$(openssl rand -base64 48) spasteg

With custom port:

docker run -p 8080:3000 -e SECRET_KEY_BASE=$(openssl rand -base64 48) -e PORT=3000 spasteg

The container exposes port 3000 and runs as a non-root user with a health check configured.

Usage

Visit http://localhost:3000
Enter your text in the form
Click "Create Paste"
Share the generated URL
The paste auto-destructs after first access

Note: the creator cannot see their post with the copied link (except in private browsing) - it would be burned immediately.

License

This project is licensed under the GNU General Public License v3.0 or later (GPLv3+). See the LICENSE file for details.