Global USE flags

Flag Description Packages
X 6
alsa Enable alsa output for sound emulation 5
dbus 3
debug 2
doc 4
gnutls Enable TLS support for the VNC console server. For 1.4 and newer this also enables WebSocket support. For 2.0 through 2.3 also enables disk quorum support. 2
gtk 2
introspection 2
jack 2
nls 2
opengl 2
oss 2
pam 2
plugins Enable qemu plugin API via shared library loading. 2
pulseaudio Enable pulseaudio output for sound emulation 4
sdl Enable the SDL-based console 2
seccomp Enable sandboxing functionality through <pkg>sys-apps/bubblewrap</pkg> 2
sndio Enable support for sndio 2
speech Enable text-to-speech support 2
static Build the User and Software MMU (system) targets as well as tools as static binaries 6
static-libs 4
system Install utils-std as system utilities in /usr 2
test 27
tools Enable the Godot Editor for game development 2
udev 2
usb Enable USB passthrough via <pkg>dev-libs/libusb</pkg> 2
vulkan Compile vulkan backend 2
wayland 3

Local USE flags

app-accessibility

julius

Flag Description
portaudio
sndfile

app-crypt

uacme

Flag Description
mbedtls
openssl
ualpn

app-emulation

qemu

Flag Description
$(printf
accessibility Adds support for braille displays using brltty
aio Enables support for Linux's Async IO
bpf Enable eBPF support for RSS implementation.
bzip2
capstone Enable disassembly support with <pkg>dev-libs/capstone</pkg>
curl Support ISOs / -cdrom directives via HTTP or HTTPS.
fdt Enables firmware device tree support
fuse Enables FUSE block device export
glusterfs Enables GlusterFS cluster fileystem via <pkg>sys-cluster/glusterfs</pkg>
infiniband
iscsi Enable direct iSCSI support via <pkg>net-libs/libiscsi</pkg> instead of indirectly via the Linux block layer that <pkg>sys-block/open-iscsi</pkg> does.
jemalloc
jpeg Enable jpeg image support for the VNC console server
lzo
multipath Enable multipath persistent reservation passthrough via <pkg>sys-fs/multipath-tools</pkg>.
ncurses Enable the ncurses-based console
nfs Enable NFS support
numa Enable NUMA support
pin-upstream-blobs Pin the versions of BIOS firmware to the version included in the upstream release. This is needed to sanely support migration/suspend/resume/snapshotting/etc... of instances. When the blobs are different, random corruption/bugs/crashes/etc... may be observed.
png Enable png image support for the VNC console server
python
rbd Enable rados block device backend support, see https://docs.ceph.com/en/mimic/rbd/qemu-rbd/
sasl
sdl-image SDL Image support for icons
selinux
slirp Enable TCP/IP in hypervisor via <pkg>net-libs/libslirp</pkg>
smartcard
snappy
spice Enable Spice protocol support via <pkg>app-emulation/spice</pkg>
ssh Enable SSH based block device support via <pkg>net-libs/libssh2</pkg>
static-user Build the User targets as static binaries
systemtap Enable SystemTap/DTrace tracing
usbredir Use <pkg>sys-apps/usbredir</pkg> to redirect USB devices to another machine over TCP
vde Enable VDE-based networking
vhost-net Enable accelerated networking using vhost-net, see https://www.linux-kvm.org/page/VhostNet
virgl Enable experimental Virgil 3d (virtual software GPU)
virtfs Enable VirtFS via virtio-9p-pci / fsdev. See https://wiki.qemu.org/Documentation/9psetup
vnc
vte Enable terminal support (<pkg>x11-libs/vte</pkg>) in the GTK+ interface
xattr Add support for getting and setting POSIX extended attributes, through <pkg>sys-apps/attr</pkg>. Requisite for the virtfs backend.
xen Enables support for Xen backends
zstd

dev-games

godot

Flag Description
bullet Enable the <pkg>sci-physics/bullet</pkg> module
deprecated Enable support for deprecated features
fontconfig
gui
raycast Enable the raycast Editor module using <pkg>media-libs/embree</pkg>
runner Build an additional binary optimized for running games (only relevant with USE=tools)
theora
upnp
webm Enable the WebM module
webp

dev-vcs

got

Flag Description
bearssl Use bearssl as LibTLS provider
cvg enable support for cvs-like-git (experimental)

games-arcade

emilia-pinball

Flag Description
gles1-only Use GLES 1.0 instead of OpenGL

games-emulation

flycast

Flag Description
ao
lua
openmp

games-fps

assaultcube-reloaded

Flag Description
system-enet

gnome-base

librsvg

Flag Description
vala

media-fonts

iosevka-src

Flag Description
autohint
savedconfig

media-gfx

synfig

Flag Description
imagemagick
mlt

media-libs

portmidi

Flag Description
test-programs Install various example programs

smpeg2

Flag Description
cpu_flags_x86_mmx

media-video

adobe-flashplayer-projector

Flag Description
debugger

net-libs

webkit-gtk

Flag Description
aqua
avif Enable AVIF support via <pkg>media-libs/libavif</pkg>
egl Enable EGL support
examples
gamepad Enable gamepad support via <pkg>dev-libs/libmanette</pkg>
geolocation Enable geolocation support through <pkg>app-misc/geoclue</pkg>
gles2-only Use GLES 2.0 or later instead of full OpenGL
gstreamer
jpegxl Enable JPEG-XL support via <pkg>media-libs/libjxl</pkg>
jumbo-build Combine source files to speed up build process
keyring
lcms
pdf
skia
spell
sysprof
systemd
webrtc Enable WebRTC support

net-mail

checkpassword-ng

Flag Description
suid

net-misc

drawterm

Flag Description
fbdev
pipewire

sys-apps

utils-std

Flag Description
md5sum Provide an md5sum(1) implementation
multicall Build all tools into a single `utils-std` program akin to busybox to save space

sys-auth

skeud

Flag Description
suc Install the suc(1) utility

sys-devel

binutils-x86_64-helios

Flag Description
cet Enable Intel Control-flow Enforcement Technology.
default-gold Set ld to point to ld.gold instead of ld.bfd
gold Build ld.gold linker
gprofng Enable the next-generation gprofng profiler
hardened
multitarget Adds support to binutils for cross compiling (does not work with gas)
vanilla

gettext

Flag Description
shim Install libintl library. Not suitable on glibc systems. On musl systems, passes contents through and translates via musl's libintl. On other systems, provides a no-op library (returns input text with no changes/translations).

sys-firmware

ipxe

Flag Description
binary Use pre-built binaries
ipv6
iso Build a bootable ISO for using PXE
lkrn Build a linux kernel bootable file for using with grub/etc...
qemu Build the required PXE ROM images for <pkg>app-emulation/qemu</pkg>
uefi32 Build a 32bit EFI program for using PXE
uefi64 Build a 64bit EFI program for using PXE
undi Build a Universal Network Device Interface driver chainloading your existing PXE NIC into iPXE
vmware Build the PXE ROM images that VMWare uses

sys-libs

libtickit

Flag Description
unibilium Use <pkg>dev-libs/unibilium</pkg> (highly recommended) instead of <pkg>sys-libs/ncurses</pkg>

x11-themes

adwaita-qt

Flag Description
gnome