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I already got used to auto-starting services when they run with docker compose or docker stack, but I like it even more when the apps run natively without extra layers of virtual networks or file systems and mounting. And this is where systemd, a thing that is in every modern Linux distribution by default, will do that for us. But we will need to write a service file first. And the syntax is INI and it's not very user-friendly.

As far as I remember, all the configs have three sections. It's either Service and Unit and Install. The middle one is a core - where you specify

  • how to run this thing (what executable and what arguments)
  • set environment variables
  • how and when to restart
  • where to write logs
  • working directory and permissions
  • maybe something else, but I don't really go so hardcore about this thing

So let me try to create one from memory for a bookmark tool / offline reader I recently got obssessed with - Readeck. This will demonstrate how their awkward syntax prevents me from using systemd extensively. That's why I always need to keep a template nearby, and if I were to write this from memory, it would turn out something like this

[Service]
Name = Readeck

[Unit]
Type=simple
WorkingDirectory=/home/nikolay/readeck
Exec=/home/nikolay/readeck
User=nikolay
Group=nikolay

[Install]
Wanted-by = multiuser.target

The last section has a weird name, Install, that's why I remembered it. It's like when you write instructions for the CMake build system for local development when you never plan to specify details on how it should be installed system-wise.

Why didn't you just make it so people could create a service file using a single line

Run=/home/nikolay/readeck

and systemd would use default values for other parameters. But no.

In order this thing really to work we need to make the following corrections.

Section order: [Unit] should come first, followed by [Service], then [Install].

Fix syntax errors:

  • Remove spaces around = signs
    • Name= → Description=
  • Exec= → ExecStart=
  • Wanted-by → WantedBy
  • multiuser.target → multi-user.target

Add helpful directives I missed:

  • After=network.target ensures network is available before starting
  • Restart=always automatically restarts on failure
  • RestartSec=5 waits 5 seconds before restarting

The result

[Unit]
Description=Readeck - Self-hosted bookmark manager
After=network.target

[Service]
Type=simple
User=nikolay
Group=nikolay
WorkingDirectory=/home/nikolay/readeck
ExecStart=/home/nikolay/readeck/readeck
Restart=always
RestartSec=5
StandardOutput=journal
StandardError=journal
SyslogIdentifier=readeck

[Install]
WantedBy=multi-user.target

So this will be for my headless little bolt computer (it ain't cheap, but I got it for free as a decommissioned peace from work).

And we will be installing this fresh file into a place where systemd can see it and where usually you should put your manually created services: /etc/systemd/system (/usr/lib/systemd/system is used by package managers and it is very crowded)

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