[Unit]
Description=service mautrix-syncproxy
Documentation=https://github.com/mautrix/syncproxy

After=network.target

[Service]
User=mautrix-syncproxy
Group=mautrix-syncproxy
EnvironmentFile=/etc/default/mautrix-syncproxy
ExecStart=/usr/bin/mautrix-syncproxy
WorkingDirectory=/var/lib/mautrix-syncproxy
Restart=on-failure
RestartSec=30s
ReadWritePaths=/var/lib/mautrix-syncproxy
NoNewPrivileges=yes
MemoryDenyWriteExecute=true
PrivateDevices=yes
PrivateTmp=yes
ProtectHome=yes
ProtectSystem=strict
ProtectControlGroups=true
RestrictSUIDSGID=true
RestrictRealtime=true
LockPersonality=true
ProtectKernelLogs=true
ProtectKernelTunables=true
ProtectHostname=true
ProtectKernelModules=true
PrivateUsers=true
ProtectClock=true
SystemCallArchitectures=native
SystemCallErrorNumber=EPERM
SystemCallFilter=@system-service

[Install]
WantedBy=multi-user.target

source : https://www.freedesktop.org/software/systemd/man/systemd.service.html