Atlantis is a privacy-first, self-hosted web app for creating and editing beautiful Mermaid.js diagrams alongside simple notes, all stored locally, with zero data sent to external services. It offers a clean split-pane editor (Mermaid code on the left, live diagram on the right), full support for every Mermaid diagram type, interactive Markdown todo lists, fast full-text search, favorites, recent version checkpoints, and easy JSON backup/restore. Built with Next.js, Tailwind, and shadcn/ui, it features a modern responsive design. In this step by step guide I will show you how to install Atlantis on your Synology NAS using Docker and Portainer.

💡Note: This guide works perfectly with the latest Atlantis Main Tag release.

• STEP 1

Please Support My work by Making a Donation.

• STEP 2

Install Portainer using my step by step guide. If you already have Portainer installed on your Synology NAS, skip this STEP. Attention: Make sure you have installed the latest Portainer version.

• STEP 3

Go to File Station and open the docker folder. Inside the docker folder, create one new folder and name it atlantis. Follow the instructions in the image below.
Note: Be careful to enter only lowercase, not uppercase letters.

• STEP 4

Now create three new folders inside the atlantis folder that you have previously created at STEP 3 and name them data, db, redis. Follow the instructions in the image below.
Note: Be careful to enter only lowercase, not uppercase letters.

• STEP 5

Log into Portainer using your username and password. On the left sidebar in Portainer, click on Home then Live connect. Follow the instructions in the image below.

On the left sidebar in Portainer, click on Stacks then + Add stack. Follow the instructions in the image below.

• STEP 6

In the Name field type in atlantis. Follow the instructions in the image below.

Note: Copy Paste the code below in the Portainer Stacks Web editor.

services:
  atlantis:
    image: strikead/atlantis:latest
    container_name: Atlantis
    healthcheck:
      test: ["CMD-SHELL", "nc -z 127.0.0.1 3000 || exit 1"]
      interval: 10s
      timeout: 5s
      retries: 3
      start_period: 90s
    ports:
      - 3021:3000
    volumes:
      - /volume1/docker/atlantis/data:/app/data:rw
    environment:
       NODE_ENV: production
       ENABLE_API_ACCESS: false
       REDIS_URL: redis://redis:6379
       DATABASE_URL: postgresql://atlantisuser:atlantispass@atlantis-db:5432/atlantis
    depends_on:
      redis:
        condition: service_healthy
      db:
        condition: service_healthy
    restart: on-failure:5

  db:
    image: postgres:18
    container_name: Atlantis-DB
    hostname: atlantis-db
    security_opt:
      - no-new-privileges:true
    healthcheck:
      test: ["CMD", "pg_isready", "-q", "-d", "resume", "-U", "resumeuser"]
      timeout: 45s
      interval: 10s
      retries: 10
    volumes:
      - /volume1/docker/atlantis/db:/var/lib/postgresql:rw
    environment:
      POSTGRES_DB: atlantis
      POSTGRES_USER: atlantisuser
      POSTGRES_PASSWORD: atlantispass
    restart: on-failure:5

  redis:
    image: redis
    hostname: atlantis-redis
    container_name: Atlantis-REDIS
    user: 1026:100
    healthcheck:
     test: ["CMD-SHELL", "redis-cli ping || exit 1"]
    volumes:
      - /volume1/docker/atlantis/redis:/data:rw
    environment:
      TZ: Europe/Bucharest
    restart: on-failure:5

Note: Before you paste the code above in the Web editor area below, change the value numbers for user with your own UID and GID values. (Follow my step by step guide on how to do this.) 1026 is my personal UID value and 100 is my personal GID value. You have to type in your own values.
Note: Before you paste the code above in the Web editor area below, change the value for TZ. (Select your current Time Zone from this list.)

• STEP 7

Scroll down on the page until you see a button named Deploy the stack. Click on it. Follow the instructions in the image below. The installation process can take up to a few minutes. It will depend on your Internet speed connection.

• STEP 8

If everything goes right, you will see the following message at the top right of your screen: “Success Stack successfully deployed“.

• STEP 9

🟢Please Support My work by Making a Donation. Almost 99,9% of the people that install something using my guides forget to support my work, or just ignore STEP 1. I’ve been very honest about this aspect of my work since the beginning: I don’t run any ADS, I don’t require subscriptions, paid or otherwise, I don’t collect IPs, emails, and I don’t have any referral links from Amazon or other merchants. I also don’t have any POP-UPs or COOKIES. I have repeatedly been told over the years how much I have contributed to the community. It’s something I love doing and have been honest about my passion since the beginning. But I also Need The Community to Support me Back to be able to continue doing this work.

• STEP 10

Please wait approximately 2 minutes for the installation to be completed or you will get a blank page if you try to connect too soon. The installation process can take up to a few seconds/minutes. It will depend on your Internet speed connection. Now open your browser and type in http://Synology-ip-address:3021 Click Settings. Follow the instructions in the image below.

• STEP 11

Switch the Light theme to Dark. Follow the instructions in the image below.

• STEP 12

Go back to the main page. Click + New Diagram. Follow the instructions in the image below.

• STEP 13

Your Diagram at a glance! Save it when you are done!

Enjoy Atlantis!

🆘TROUBLESHOOTING

If you encounter issues by using this container, make sure to check out the Common Docker issues article.

Note: If you want to run the Atlantis container over HTTPS, check How to Run Docker Containers Over HTTPS. In order to make Atlantis work via HTTPS, it’s mandatory to activate WebSocket.

Note: Can I run Docker on my Synology NAS? See the supported models.
Note: How to Back Up Docker Containers on your Synology NAS.
Note: Find out how to update the Atlantis Controller container with the latest image.
Note: How to Free Disk Space on Your NAS if You Run Docker.
Note: How to Schedule Start & Stop For Docker Containers.
Note: How to Activate Email Notifications.
Note: How to Add Access Control Profile on Your NAS.
Note: How to Change Docker Containers Restart Policy.
Note: How to Use Docker Containers With VPN.
Note: Convert Docker Run Into Docker Compose.
Note: How to Clean Docker.
Note: How to Clean Docker Automatically.
Note: Best Practices When Using Docker and DDNS.
Note: Some Docker Containers Need WebSocket.
Note: Find out the Best NAS Models For Docker.
Note: Activate Gmail SMTP For Docker Containers.