Joplin is a note-taking app, which allows you to take control of your notes empire including self-hosting the synchronization server. Joplin is available for multiple desktop and mobile operating servers here: https://joplinapp.org/. The apps work standalone and do not require a central server to work. However, synchronization across apps does require an intermediate server.

Joplin does offer a cloud option to support synchronization, but you may also host this for yourself with linux machine and a docker container. For the server, I use a small Raspberry Pi 5, which has ample power to host Joplin Server in addition to several other services.

Hosting Joplin Server requires that you have docker installer. If you find that it is not installed follow the instruction for you operating system posted here: https://docs.docker.com/engine/install/.

With docker running create a directory to host the docker configuration, e.g., sudo mkdir /opt/joplin

In that directory, create a file docker-compose.yml (e.g., sudo nano docker-compose.yml) with the following content:

    db:
        image: postgres:17.6
        restart: unless-stopped
        volumes:
            - ./db:/var/lib/postgresql/data
        environment:
            - POSTGRES_PASSWORD=POSTGRES_PASSWORD
            - POSTGRES_USER=joplin
            - POSTGRES_DB=joplin
    app:
        image: joplin/server:3.5.2
        environment:
            - APP_BASE_URL=APP_BASE_URL
            - APP_PORT=22300
            - POSTGRES_PASSWORD=POSTGRES_PASSWORD
            - POSTGRES_DATABASE=joplin
            - POSTGRES_USER=joplin
            - POSTGRES_PORT=5432
            - POSTGRES_HOST=db
            - DB_CLIENT=pg
        restart: unless-stopped
        ports:
            - "22300:22300"
        depends_on:
            - db

Replace APP_BASE_URL with the URL of your server, and POSTGRESS_PASSWORD with a strong password for your notes database.

Start the Joplin server with: docker compose up -d

Visit your Joplin server URL in the browser and log in with
Email: admin@localhost
Password: admin

Change the password of the admin user and create account for the user.

Finally, in the app go to Settings -> Synchronization and set the URL of the synchronization server. Notes should now synchronize automatically or when you hit the "Synchronize" button.

Enjoy!