Install with the bash script from the opencode website:

curl -fsSL https://opencode.ai/install | bash

verify with:

opencode --version

sudo vi /etc/systemd/system/opencode.service
add:

[Unit]
Description=OpenCode AI Assistant
After=network.target

[Service]
Type=simple
User=abel
WorkingDirectory=%h/opencode/projects
ExecStart=/usr/local/bin/opencode web --port 4096 --hostname 0.0.0.0
Restart=always
RestartSec=10

[Install]
WantedBy=multi-user.target

User=abel seems unsafe but that is how it works, and seeing as it is on the personal workstation any sequrity risk is minimal.