LetterSpace is a self-hosted, open-source newsletter platform alternative to ListMonk designed for managing subscribers and sending campaigns. It offers a user-friendly interface for creating and customizing newsletters, with Docker support for easy setup. Currently English-only, it’s a new but robust tool for streamlined email marketing. In this step by step guide I will show you how to install LetterSpace on your Synology NAS using Docker & Portainer.

💡Note: This guide works perfectly with the latest LetterSpace v0.8.1 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

Make sure you have a synology.me Wildcard Certificate. Follow my guide to get a Wildcard Certificate. If you already have a synology.me Wildcard certificate, skip this STEP.

• STEP 4

Go to Control Panel / Login Portal / Advanced Tab / click Reverse Proxy. Follow the instructions in the image below.

• STEP 5

Now click the “Create” button. Follow the instructions in the image below.

• STEP 6

After you click the Create button, the window below will open. Follow the instructions in the image below.

On the General area, set the Reverse Proxy Name description: type in LetterSpace. After that, add the following instructions:

Source:
Protocol: HTTPS
Hostname: letterspace.yourname.synology.me
Port: 443

Check Enable HSTS

Destination:
Protocol: HTTP
Hostname: localhost
Port: 5455

• STEP 7

On the Reverse Proxy Rules click the Custom Header tab. Click Create and then, from the drop-down menu, click WebSocket. After you click on WebSocket, two Header Names and two Values will be automatically added. Click Save. Follow the instructions in the image below.

• STEP 8

Go to Control Panel / Network / Connectivity tab/ Check Enable HTTP/2 then click Apply. Follow the instructions in the image below.

• STEP 9

Go to Control Panel / Security / Advanced tab/ Check Enable HTTP Compression then click Apply. Follow the instructions in the image below.

• STEP 10

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

• STEP 11

Log into Portainer using your username and password. On the left sidebar in Portainer, click on Stacks then + Add stack. Follow the instructions in the image below.

• STEP 12

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

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

services:
  db:
    image: postgres:17
    container_name: LetterSpace-DB
    hostname: letterspace-db
    security_opt:
      - no-new-privileges:true
    healthcheck:
      test: ["CMD", "pg_isready", "-q", "-d", "letterspace", "-U", "letterspaceuser"]
      timeout: 45s
      interval: 10s
      retries: 10
    volumes:
      - /volume1/docker/letterspacedb:/var/lib/postgresql/data:rw
    environment:
      POSTGRES_DB: letterspace
      POSTGRES_USER: letterspaceuser
      POSTGRES_PASSWORD: letterspacepass
    restart: on-failure:5
    
  backend:
    image: ghcr.io/dcodesdev/letterspace:latest-node
    container_name: LetterSpace
    healthcheck:
      test: timeout 10s bash -c ':> /dev/tcp/127.0.0.1/5000' || exit 1
      interval: 10s
      timeout: 5s
      retries: 3
      start_period: 90s  
    depends_on:
      - db
    ports:
      - 5455:5000
    environment:
      DATABASE_URL: postgresql://letterspaceuser:letterspacepass@letterspace-db:5432/letterspace?schema=public
      JWT_SECRET: TByJvIXVbkgGyZBFEcWAwmOBByWzwhcV
    restart: on-failure:5

Note: Before you paste the code above in the Web editor area below, change the value for JWT_SECRET. (Generate your own Random 32 length JWT_SECRET.)

• STEP 13

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 14

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

• STEP 15

🟢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 17

Now open your browser and type in your HTTPS/SSL certificate like this https://letterspace.yourname.synology.me In my case it’s https://letterspace.mariushosting.synology.me If everything goes right, you will see the LetterSpace setup page. Type in your Full Name, Email and Password. Click Create account. Follow the instructions in the image below.

• STEP 18

In the apposite field, type in your Organization name and Description. Click Create Organization. Follow the instructions in the image below.

• STEP 19

Your LetterSpace dashboard at a glance!

• STEP 20

Follow my step by step guide on how to activate SMTP for your Gmail account. This step is mandatory. Note: If you don’t want to use the easiest way for SMTP with Google and you already have SMTP details from your own Mail Server, you can just skip this STEP and use your personalized email SMTP details instead.

• STEP 21

On the left sidebar, click Settings. Click the SMTP tab, then add the details below.

On the SMTP Host field, type in smtp.gmail.com
On the Port field, type in 587
On the Encryption field, select STARTTLS
On the Username field, type in your own Gmail address. / STEP 20
On the Password field, type in your own Gmail App Password / STEP 20
On the From Email field, type in your own Gmail address. / STEP 20
On the From Name field, type in your own Organization name that you have previously added at STEP 18.
Click Save. Click Test Settings. Follow the instructions in the image below.

• STEP 22

Check your Gmail Email!

• STEP 23

Start your Email Campaign!

Enjoy LetterSpace!

🆘TROUBLESHOOTING

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

Note: Find out how to update the LetterSpace container with the latest image.
Note: How to Back Up Docker Containers on your Synology NAS.
Note: Can I run Docker on my Synology NAS? See the supported models.
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.

This post was updated on Wednesday / May 14th, 2025 at 12:37 AM