What Is HedgeDoc?

HedgeDoc is a self-hosted, real-time collaborative Markdown editor. Share a link and multiple people can edit the same document simultaneously — like Google Docs, but for Markdown. It’s the open-source successor to CodiMD (and before that, HackMD). HedgeDoc is ideal for meeting notes, documentation drafts, and any situation where you need shared, live-editing Markdown without a cloud service.

Prerequisites

A Linux server (Ubuntu 22.04+ recommended)
Docker and Docker Compose installed (guide)
500 MB of free disk space
512 MB of RAM (minimum)
A domain name (recommended for sharing notes)

Docker Compose Configuration

Create a docker-compose.yml file:

services:
  hedgedoc:
    image: quay.io/hedgedoc/hedgedoc:1.10.2
    container_name: hedgedoc
    restart: unless-stopped
    ports:
      - "3000:3000"
    environment:
      # Database connection
      CMD_DB_URL: "postgres://hedgedoc:your_db_password@hedgedoc-db:5432/hedgedoc"

      # REQUIRED — Domain where HedgeDoc is accessed
      # Must include protocol. Used for generating share links.
      CMD_DOMAIN: "hedgedoc.example.com"
      CMD_PROTOCOL_USESSL: "true"
      CMD_URL_ADDPORT: "false"

      # Session secret — generate with: openssl rand -hex 32
      CMD_SESSION_SECRET: "CHANGE_ME_GENERATE_RANDOM_HEX_STRING"

      # Registration and permissions
      CMD_ALLOW_ANONYMOUS: "true"       # Allow anonymous editing (no login)
      CMD_ALLOW_ANONYMOUS_EDITS: "true" # Allow anonymous users to edit shared notes
      CMD_EMAIL: "true"                 # Enable email/password registration
      CMD_ALLOW_EMAIL_REGISTER: "true"  # Allow new account creation

      # Image uploads
      CMD_IMAGE_UPLOAD_TYPE: "filesystem"
      CMD_UPLOADS_DIR: "/hedgedoc/public/uploads"
    volumes:
      - hedgedoc-uploads:/hedgedoc/public/uploads
    depends_on:
      hedgedoc-db:
        condition: service_healthy

  hedgedoc-db:
    image: postgres:16-alpine
    container_name: hedgedoc-db
    restart: unless-stopped
    environment:
      POSTGRES_USER: hedgedoc
      POSTGRES_PASSWORD: your_db_password  # CHANGE THIS — must match CMD_DB_URL
      POSTGRES_DB: hedgedoc
    volumes:
      - hedgedoc-pgdata:/var/lib/postgresql/data
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U hedgedoc"]
      interval: 10s
      timeout: 5s
      retries: 5

volumes:
  hedgedoc-uploads:
  hedgedoc-pgdata:

Start the stack:

docker compose up -d

Initial Setup

Open https://hedgedoc.example.com (or http://your-server-ip:3000). You’ll see the HedgeDoc landing page with options to create a new note.

Create an account — click “Sign In” and register with email/password (if CMD_EMAIL is enabled).
Create your first note — click “New Note” or visit /new. Start typing Markdown on the left; see the rendered preview on the right.
Share a note — copy the URL from your browser. Anyone with the link can view (and edit, if anonymous editing is enabled).

Configuration

Permission Modes

Each note has a permission level:

Freely — anyone with the link can edit
Editable — logged-in users can edit, anonymous can view
Limited — only the owner can edit, others can view
Locked — only the owner can view and edit
Protected — logged-in users can view, only owner can edit
Private — only the owner can access

Set the default with CMD_DEFAULT_PERMISSION:

CMD_DEFAULT_PERMISSION: "editable"

Authentication Options

HedgeDoc supports multiple auth providers:

# LDAP
CMD_LDAP_URL: "ldap://your-ldap-server"
CMD_LDAP_BINDDN: "cn=admin,dc=example,dc=com"
CMD_LDAP_BINDCREDENTIALS: "ldap_password"
CMD_LDAP_SEARCHBASE: "dc=example,dc=com"

# OAuth2 / OIDC (works with Keycloak, Authentik, etc.)
CMD_OAUTH2_BASEURL: "https://auth.example.com"
CMD_OAUTH2_CLIENT_ID: "hedgedoc"
CMD_OAUTH2_CLIENT_SECRET: "your_client_secret"
CMD_OAUTH2_AUTHORIZATION_URL: "https://auth.example.com/authorize"
CMD_OAUTH2_TOKEN_URL: "https://auth.example.com/token"
CMD_OAUTH2_USER_PROFILE_URL: "https://auth.example.com/userinfo"

# GitHub, GitLab, Google, Twitter, etc. also supported

Image Upload Options

# Local filesystem (default)
CMD_IMAGE_UPLOAD_TYPE: "filesystem"

# S3-compatible storage
CMD_IMAGE_UPLOAD_TYPE: "s3"
CMD_S3_BUCKET: "hedgedoc-uploads"
CMD_S3_ENDPOINT: "https://s3.example.com"
CMD_S3_ACCESS_KEY_ID: "your_key"
CMD_S3_SECRET_ACCESS_KEY: "your_secret"

# Imgur (public uploads)
CMD_IMAGE_UPLOAD_TYPE: "imgur"
CMD_IMGUR_CLIENTID: "your_imgur_client_id"

Disabling Registration

To run HedgeDoc as a private instance (no new signups):

CMD_ALLOW_EMAIL_REGISTER: "false"
CMD_ALLOW_ANONYMOUS: "false"

Create accounts manually or use an external auth provider.

Advanced Configuration (Optional)

Custom Branding

CMD_TITLE: "Team Notes"             # Page title
CMD_DEFAULT_USE_HARD_BREAK: "true"  # Hard line breaks in Markdown
CMD_HSTS_ENABLE: "true"             # HTTP Strict Transport Security
CMD_CSP_ENABLE: "true"              # Content Security Policy

Slide Mode

HedgeDoc can render Markdown as presentation slides using reveal.js. Add --- between slides in your document and access /slide/note-id for the presentation view. No extra configuration needed.

Note Aliases

Set custom URLs for notes by adding --- YAML frontmatter:

---
permalink: /team-meeting-notes
---
# Team Meeting Notes
...

Reverse Proxy

HedgeDoc runs on port 3000. Point your reverse proxy to http://hedgedoc:3000.

WebSocket support is required for real-time collaboration. Ensure your reverse proxy passes WebSocket upgrade headers:

Nginx:

location / {
    proxy_pass http://hedgedoc:3000;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection "upgrade";
    proxy_set_header Host $host;
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header X-Forwarded-Proto $scheme;
}

Set CMD_DOMAIN, CMD_PROTOCOL_USESSL, and CMD_URL_ADDPORT to match your reverse proxy setup. See Reverse Proxy Setup.

Backup

Back up two things:

PostgreSQL database — all notes, user accounts, permissions
Uploads volume — images and files uploaded to notes

# Database backup
docker exec hedgedoc-db pg_dump -U hedgedoc hedgedoc > hedgedoc-db-$(date +%Y%m%d).sql

# Uploads backup
docker run --rm -v hedgedoc_hedgedoc-uploads:/data -v $(pwd):/backup alpine \
  tar -czf /backup/hedgedoc-uploads-$(date +%Y%m%d).tar.gz /data

See Backup Strategy for a comprehensive approach.

Troubleshooting

Real-Time Collaboration Not Working

Symptom: Multiple users can’t see each other’s changes in real time.

Fix: WebSocket connections are required. Check your reverse proxy configuration — it must pass Upgrade and Connection headers. If using Nginx Proxy Manager, enable “WebSockets Support” for the proxy host.

”Forbidden” Error on Note Access

Symptom: Users get a 403 error when opening a note link.

Fix: Check CMD_ALLOW_ANONYMOUS. If set to false, users must log in before viewing any notes. If you want public read access, set:

CMD_ALLOW_ANONYMOUS: "true"
CMD_ALLOW_ANONYMOUS_EDITS: "false"

Images Not Loading

Symptom: Uploaded images show as broken links.

Fix: If using filesystem uploads, ensure the uploads volume is mounted correctly. If CMD_DOMAIN doesn’t match the actual access URL, image URLs will be wrong. Double-check CMD_DOMAIN and CMD_PROTOCOL_USESSL.

Database Connection Failed

Symptom: HedgeDoc crashes on startup with “connection refused” or “authentication failed.”

Fix: Verify CMD_DB_URL matches the PostgreSQL container’s credentials. The format is:

postgres://USER:PASSWORD@HOST:PORT/DBNAME

Ensure the database container is healthy before HedgeDoc starts (the healthcheck in the config above handles this).

Notes Lost After Upgrade

Symptom: After updating the HedgeDoc image, notes are gone.

Fix: Notes are in PostgreSQL, not in the HedgeDoc container. Ensure your hedgedoc-pgdata volume persists. If you accidentally removed the volume, restore from backup.

Resource Requirements

RAM: ~150-200 MB idle (HedgeDoc + PostgreSQL), ~300-500 MB under active collaborative editing
CPU: Low for editing. Moderate spikes when rendering complex Markdown or slides
Disk: ~200 MB for the application. Database grows based on note count and uploads

Verdict

HedgeDoc is the best self-hosted option for real-time collaborative Markdown editing. The share-a-link-and-edit model is simple and intuitive. Slide mode is a nice bonus. If your team writes in Markdown and needs a shared scratch pad, HedgeDoc is the tool.

It’s not a knowledge base — there’s no folder structure, no search across notes, no wiki-style organization. For that, use BookStack or Outline. HedgeDoc is for collaborative editing sessions, meeting notes, and shared documents. For that specific use case, it’s excellent.

Etherpad is the main alternative for real-time collaborative editing, but it uses rich text instead of Markdown. If your team prefers Markdown, HedgeDoc wins.