(cross-cutting) Addresses deployment friction in NixOS by using systemd-nspawn containers instead of monolithic redeployment. Managing multiple project repositories requires constant config updates on the main system. systemd-nspawn provides lightweight containers that integrate seamlessly with systemd—systemctl commands show the full service tree across host and containers, and systemd-machined handles automatic service discovery. This approach enables isolated project deployments without touching the core NixOS configuration, solving the problem of frequent redeploys for small changes.