Enable use of systemd-specific libraries and features like socket activation or session tracking
| Package | “systemd” Flag Description | 
|---|---|
| app-admin/openrc-settingsd | Use the versions of dbus and polkit files provided by sys-apps/systemd | 
| app-admin/rsyslog | Build the journal input and output module (requires sys-apps/systemd) | 
| app-crypt/libu2f-host | Use user ACLs rather than plugdev group to give user access to the HIDRAW device. | 
| dev-cpp/sdbus-c++ | Use external libsystemd instead of statically-linked build | 
| gnome-base/gnome-settings-daemon | Rely on sys-apps/systemd as runtime logind provider | 
| gnome-extra/gnome-system-monitor | Display sys-apps/systemd metadata, e.g. unit names, for running processes | 
| gui-libs/vte | Support moving terminal child processes to their own systemd user scopes to avoid terminal getting killed due to child causing OOM | 
| gui-libs/vte-common | Support moving terminal child processes to their own systemd user scopes to avoid terminal getting killed due to child causing OOM | 
| media-sound/cmus | Enable MPRIS support via sys-apps/systemd | 
| media-sound/mpd | Enable support for systemd socket activation | 
| media-sound/pulseaudio-daemon | Build with sys-apps/systemd support to replace standalone ConsoleKit. | 
| net-wireless/iwd | Use systemd-resolve rather than resolvconf for DNS handling in standalone mode | 
| sys-apps/accountsservice | Use sys-apps/systemd for session tracking | 
| sys-apps/busybox | Support systemd | 
| sys-apps/dbus | Build with sys-apps/systemd at_console support | 
| sys-apps/kmscon | Enable multiseat support via systemd | 
| sys-auth/pambase | Use pam_systemd module to register user sessions in the systemd control group hierarchy. | 
| sys-auth/polkit | Use sys-apps/systemd for session tracking | 
| sys-fs/btrfsmaintenance | Enable systemd services and timers instead of cron timers | 
| sys-fs/udisks | Support sys-apps/systemd's logind | 
| sys-kernel/installkernel | Use systemd's kernel-install to install kernels, overridable with SYSTEMD_KERNEL_INSTALL env var | 
| x11-libs/vte | Support moving terminal child processes to their own systemd user scopes to avoid terminal getting killed due to child causing OOM |