Slash is a bookmarking and short link service that allows you to save and share links easily. It lets you store and categorize links, generate short URLs for easy sharing, search and filter your saved links, and access them from any device. In this step by step guide I will show you how to install Slash with PostgreSQL as database on your Synology NAS using Docker & Portainer. PostgreSQL has a well-constructed user management system which can handle multiple users and grant various levels of permission. SQLite is suitable for smaller databases. As the Slash database grows, the memory requirement also gets larger while using SQLite. Performance optimization is harder when using SQLite so PostgreSQL is the solution. Note: If you want to install Slash without PostgreSQL as database, follow my other Slash Installation guide.

💡Note: This guide works perfectly with the latest Slash v0.5.3 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 Slash. After that, add the following instructions:

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

Check Enable HSTS

Destination:
Protocol: HTTP
Hostname: localhost
Port: 5231

• 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 slash. Follow the instructions in the image below.
Note: Be careful to enter only lowercase, not uppercase letters.

• STEP 11

Now create two new folders inside the slash folder that you created at STEP 10 and name them data and db. Follow the instructions in the image below.
Note: Be careful enter only lowercase, not uppercase letters.

• STEP 12

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 13

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

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

version: "3.9"
services:
  db:
    image: postgres:16
    container_name: Slash-DB
    hostname: slash-db
    mem_limit: 1g
    cpu_shares: 1024
    security_opt:
      - no-new-privileges:true
    healthcheck:
      test: ["CMD", "pg_isready", "-q", "-d", "slash", "-U", "slashuser"]
      timeout: 45s
      interval: 10s
      retries: 10
    volumes:
      - /volume1/docker/slash/db:/var/lib/postgresql/data:rw
    environment:
      POSTGRES_DB: slash
      POSTGRES_USER: slashuser
      POSTGRES_PASSWORD: slashspass
    restart: on-failure:5

  slash:
    image: yourselfhosted/slash:latest
    container_name: Slash
    hostname: slash
    security_opt:
      - no-new-privileges:true
    healthcheck:
      test: wget --no-verbose --tries=1 --spider http://localhost:5231/
    user: 1026:100
    ports:
      - 5231:5231
    environment:
      DRIVER: postgres
      DSN: 'postgresql://slashuser:slashpass@slash-db:5432/slash?sslmode=disable'
    volumes:
      - /volume1/docker/slash/data:/var/opt/slash:rw
    restart: on-failure:5
    depends_on:
      db:
        condition: service_healthy

Note: Before you paste the code above in the Web editor area below, change the value numbers for user with your own 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.

• STEP 14

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 15

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

• STEP 16

🟢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://slash.yourname.synology.me In my case it’s https://slash.mariushosting.synology.me If everything goes right, you will see the Slash signup page. Click Sign up. Follow the instructions in the image below.

• STEP 18

Type in your own Email Address, Nickname and Password. Click Sign up. Follow the instructions in the image below.

• STEP 19

On the left sidebar click on your profile name, then Settings. Uncheck Enable user signup then click Save. Follow the instructions in the image below.

• STEP 20

On the left sidebar click on your profile name, then Profile. Change the current white theme to Dark. Follow the instructions in the image below.

• STEP 21

Click +Create to start adding your first link. Follow the instructions in the image below.

• STEP 22

Add your custom slug name, then your long Destination URL Link. Select the tags and the visibility. Click Save. Follow the instructions in the image below.

• STEP 23

Your long url is now shorter and will look like https://slash.yourname.synology.me/s/thenameyouhavechosen.

Enjoy Slash!

🆘TROUBLESHOOTING

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

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 Slash 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.

This post was updated on Wednesday / January 8th, 2025 at 1:55 AM