schnippets/systemd/simple.service

[Unit]
Description=Service Description
ConditionPathExists=/path/that/must/exist/to/run/service

[Service]
Type=Simple
ExecStartPre=/absolute/path/to/executable --before --ExecStart
ExecStart=/absolute/path/to/executable --arg1
ExecStartPost=/absolute/path/to/executable --after --ExecStart
ExecReload=/absolute/path/to/config_test
ExecReload=/absolute/path/to/executable --reload
Restart=always
RestartSec=30s

[Install]
WantedBy=multi-user.target