[Unit]
Description=__APP__ service
Wants=postgresql.service
Wants=redis-server.service
After=redis-server.service
After=postgresql.service

[Service]
User=__APP__
Group=__APP__
WorkingDirectory=__FINALPATH__
Environment=__ADDITIONAL_ENV__
Environment=RAILS_ENV=production
Environment=UNICORN_SIDEKIQS=1
Environment=LD_PRELOAD=__LIBJEMALLOC__
Environment=UNICORN_LISTENER=__FINALPATH__/tmp/sockets/unicorn.sock
ExecStart=__RBENV_ROOT__/shims/bundle exec unicorn --config config/unicorn.conf.rb -E production
Restart=always
RestartSec=10

# Sandboxing options to harden security
# Depending on specificities of your service/app, you may need to tweak these 
# .. but this should be a good baseline
# Details for these options: https://www.freedesktop.org/software/systemd/man/systemd.exec.html
NoNewPrivileges=yes
PrivateTmp=yes
PrivateDevices=yes
RestrictAddressFamilies=AF_UNIX AF_INET AF_INET6
RestrictNamespaces=yes
RestrictRealtime=yes
DevicePolicy=closed
ProtectSystem=full
ProtectControlGroups=yes
ProtectKernelModules=yes
ProtectKernelTunables=yes
LockPersonality=yes
SystemCallFilter=~@clock @debug @module @mount @obsolete @reboot @setuid @swap

# Denying access to capabilities that should not be relevant for webapps
# Doc: https://man7.org/linux/man-pages/man7/capabilities.7.html
CapabilityBoundingSet=~CAP_RAWIO CAP_MKNOD
CapabilityBoundingSet=~CAP_AUDIT_CONTROL CAP_AUDIT_READ CAP_AUDIT_WRITE
CapabilityBoundingSet=~CAP_SYS_BOOT CAP_SYS_TIME CAP_SYS_MODULE CAP_SYS_PACCT
CapabilityBoundingSet=~CAP_LEASE CAP_LINUX_IMMUTABLE CAP_IPC_LOCK
CapabilityBoundingSet=~CAP_BLOCK_SUSPEND CAP_WAKE_ALARM
CapabilityBoundingSet=~CAP_SYS_TTY_CONFIG
CapabilityBoundingSet=~CAP_MAC_ADMIN CAP_MAC_OVERRIDE
CapabilityBoundingSet=~CAP_NET_ADMIN CAP_NET_BROADCAST CAP_NET_RAW
CapabilityBoundingSet=~CAP_SYS_ADMIN CAP_SYS_PTRACE CAP_SYSLOG 

[Install]
WantedBy=multi-user.target