[Unit]
Description=Puma HTTP Server
After=network.target

[Service]
# Foreground process (do not use --daemon in ExecStart or config.rb)
Type=simple

User=usuario1

# Specify the path to your puma application root
WorkingDirectory=/home/usuario1/sites/proyecto1

ExecStart=/bin/bash -lc '/home/usuario1/.rvm/gems/ruby-2.5.3/bin/puma -C /home/usuario1/sites/proyecto1/config/puma.rb'

Restart=always

[Install]
WantedBy=multi-user.target

$ sudo ln -s /home/usuario1/servicios/puma.service /etc/systemd/system

$ sudo systemctl enable puma.service

$ sudo systemctl start puma.service

$ sudo systemctl status puma.service
● puma.service - Puma HTTP Server
   Loaded: loaded (/home/usuario1/servicios/puma.service; enabled; vendor preset: enabled)
   Active: active (running) since Wed 2019-01-16 17:11:09 -04; 9s ago
 Main PID: 3557 (ruby)
    Tasks: 19 (limit: 4680)
   CGroup: /system.slice/puma.service
           ├─3557 puma 3.12.0 (tcp://0.0.0.0:3000,unix:///home/usuario1/sites/proyecto1/shared/sockets/puma.sock) [proyecto1]
           ├─3734 puma: cluster worker 0: 3557 [proyecto1]
           ├─3738 puma: cluster worker 1: 3557 [proyecto1]
           ├─3742 puma: cluster worker 2: 3557 [proyecto1]
           └─3745 puma: cluster worker 3: 3557 [proyecto1]

ene 16 17:11:09 servidor1 systemd[1]: Started Puma HTTP Server.
ene 16 17:11:17 servidor1 bash[3557]: [3557] Puma starting in cluster mode...
ene 16 17:11:17 servidor1 bash[3557]: [3557] * Version 3.12.0 (ruby 2.5.3-p105), codename: Llamas in Pajamas
ene 16 17:11:17 servidor1 bash[3557]: [3557] * Min threads: 1, max threads: 6
ene 16 17:11:17 servidor1 bash[3557]: [3557] * Environment: production
ene 16 17:11:17 servidor1 bash[3557]: [3557] * Process workers: 4
ene 16 17:11:17 servidor1 bash[3557]: [3557] * Phased restart available
ene 16 17:11:17 servidor1 bash[3557]: [3557] * Listening on tcp://0.0.0.0:3000
ene 16 17:11:17 servidor1 bash[3557]: [3557] * Listening on unix:///home/usuario1/sites/proyecto1/shared/sockets/puma.sock
ene 16 17:11:17 servidor1 bash[3557]: [3557] Use Ctrl-C to stop

$ sudo systemctl status puma.service