Lemma

Yet another markdown editor. Work in progress

Features

• Editing & Content
  • Rich Markdown Editing - Full-featured editor with syntax highlighting and live preview
  • Wikilinks Support - Create interconnected notes with [[wikilink]] syntax and smart autocomplete
  • Math Equations - Render beautiful mathematical expressions with MathJax support
  • Code Highlighting - Syntax highlighting for code blocks in multiple languages
• Organization & Workflow
  • File Tree Navigation - Organized folder structure with intuitive file management
  • Multi-Workspace - Manage multiple projects and note collections in one place
  • Git Integration - Built-in version control to track changes and collaborate safely
• Customization
  • Theme Flexibility - Switch between dark and light modes to match your preference

Prerequisites

• Go 1.23 or later
• Node.js 20 or later
• gcc (for go-sqlite3 package)

Configuration

Lemma is configured using environment variables.

Environment Variables

Variable	Required	Default	Description
LEMMA_ADMIN_EMAIL	Yes	-	Email address for the admin account
LEMMA_ADMIN_PASSWORD	Yes	-	Password for the admin account
LEMMA_ENV	No	production	Set to "development" to enable development mode
LEMMA_DB_URL	No	sqlite://lemma.db	Database connection string (supports sqlite://, sqlite3://, postgres://, postgresql:// prefixes)
LEMMA_WORKDIR	No	./data	Working directory for application data
LEMMA_STATIC_PATH	No	../app/dist	Path to static files
LEMMA_PORT	No	8080	Port to run the server on
LEMMA_DOMAIN	No	-	Domain name for cookie authentication
LEMMA_CORS_ORIGINS	No	-	Comma-separated list of allowed CORS origins
LEMMA_ENCRYPTION_KEY	No	auto-generated	Base64-encoded 32-byte key for encrypting sensitive data
LEMMA_JWT_SIGNING_KEY	No	auto-generated	Key used for signing JWT tokens
LEMMA_LOG_LEVEL	No	DEBUG/INFO*	Logging level (*DEBUG in dev, INFO in production)
LEMMA_RATE_LIMIT_REQUESTS	No	100	Number of allowed requests per window
LEMMA_RATE_LIMIT_WINDOW	No	15m	Duration of the rate limit window

Security Keys

Security keys (LEMMA_ENCRYPTION_KEY and LEMMA_JWT_SIGNING_KEY) are automatically generated on first startup if not provided. Keys are stored in {LEMMA_WORKDIR}/secrets/.

Important: Back up the secrets directory!

Running the backend server

1. Navigate to the server directory
2. Install dependecies: go mod tidy
3. Ensure all environment variables are set
4. Additionally set CGO_ENABLED=1 (needed for sqlite3)
5. Run the server:

   go run cmd/server/main.go
   

Running the frontend app

1. Navigate to the app directory
2. Install dependencies:

   npm install
   

3. Start the development server:

   npm start
   

   The frontend will be available at http://localhost:3000

Building for production

1. Build the frontend app:

   cd app
   npm run build
   

2. Build the backend:

   cd server
   go build -o lemma ./cmd/server
   

3. Set the LEMMA_STATIC_PATH environment variable to point to the frontend build directory
4. Run the lemma executable

Docker Support

A Dockerfile is provided for easy deployment. To build and run the Docker image:

1. Build the image:

   docker build -t lemma .
   

2. Run the container:

   docker run -p 8080:8080 -v /path/to/data:/app/data lemma
   

Upgrading

Before first stable release (1.0.0) there is not upgrade path. You have to delete the database file and start over.