Global USE flags

Flag	Description	Packages
${PYTHON_REQUIRED_USE}		2
X	Enable X11 support	4
cpu_flags_x86_ssse3		2
cuda		2
debug		4
doc	Build API documentation	19
egl	Use EGL platform, enables smooth rending in high refresh rate monitors on X11/Xwayland	3
examples		8
ffmpeg	Enable <pkg>media-video/ffmpeg</pkg> backend support	5
ftdi	Enable support for USB FTDI chips via <pkg>dev-embedded/libftdi</pkg>	3
gtk3	Enable GTK3 IM support	2
gui	Build iv (with Qt5)	5
mpi	Whether to use MPI (Message Passing Interface) or not	3
parport	Enable support for parport JTAG devices	2
python	Enable Python bindings for waveform translation	8
serial	Enable serial port communication via <pkg>dev-python/pyserial</pkg>	2
static-libs		8
systemd	Installs systemd units	2
test	Build and run tests	24
tools	Build the command-line tools	3
udev		3
usb	Enable USB communication via <pkg>dev-python/pyusb</pkg>	5
wayland	Run in wayland mode under wayland sessions, xwayland otherwise. This flag doesn't affect x11 sessions.	7

Category USE flags

app-editors

Flag	Description	Packages
kerberos		2

media-fonts

Flag	Description	Packages
regular	Regular variant	3

sci-electronics

Flag	Description	Packages
stpz	Gzip-compress installed .step models to .stpz; breaks project portability with non-Gentoo distros	2

Local USE flags

app-doc

kicad-doc

Flag	Description
${LANG_USE}
html	Generate documentation in HTML format
l10n_ca
l10n_de
l10n_en
l10n_es
l10n_fr
l10n_id
l10n_it
l10n_ja
l10n_nl
l10n_pl
l10n_ru
l10n_zh
pdf	Generate documentation in PDF format

app-i18n

fcitx-meta

Flag	Description
anthy	Install Anthy Japanese input method
bamboo	Install Bamboo Vietnamese input method
chewing	Install Chewing (Intelligent phonetic, Zhuyin/Bopomofo) input method
chinese-addons	Install Chinese addons for fcitx5
configtool	Enable GUI config tool
gtk2	Enable GTK2 IM support
gtk4	Enable GTK4 IM support
hangul	Install Hangul Korean input method
lua
m17n	Install m17n-provided input methods
qt6
rime	Install Rime Chinese input method
skk	Install SKK Japanese input method

dev-embedded

openocd

Flag	Description
capstone	Use <pkg>dev-libs/capstone</pkg> for disassembly support
cmsis-dap	Support for CMSIS-DAP compliant adapters
dummy	Build the dummy port driver
gpiod	Enable Linux GPIO bitbang support via libgpiod
jlink	Build the SEGGER J-Link driver
verbose-io	Verbose IO and comm JTAG and USB messages

sdcc

Flag	Description
boehm-gc	Enable Hans Boehm's garbage collector <pkg>dev-libs/boehm-gc</pkg>
device-lib	Enable built of devices libraries
ds390	Add support for Dallas DS390
ds400	Add support for Dallas DS400
ez80-z80	Add support for EZ80-Z80
hc08	Add support for Freescale/Motorola HC08 based
mcs51	Add support for Intel mcs51
mos6502	Add support for MOS 6502
mos65c02	Add support for MOS 65C02
non-free	Enable non-free runtime library parts
packihx	Enable Intel HEX files pack utility
pdk13	Add support for PDK13
pdk14	Add support for PDK14
pdk15	Add support for PDK15
pdk16	Add support for PDK16
pic14	Add support for Microchip 14 bits PICs
pic16	Add support for Microchip 16 bits PICs
r2k	Add support for Rabbit 2000
r2ka	Add support for Rabbit 2000A
r3ka	Add support for Rabbit 3000A
s08	Add support for Freescale/Motorola S08
sdcdb	Enable SDCC source level debugger
sdcpp	Enable SDCC preprocessor based on GCC cpp
sm83	Add support for Gameboy SM83
stm8	Add support for STMicroelectronics STM8
tlcs90	Add support for TLCS-90
ucsim	Enable software simulator for microcontrollers
z180	Add support for Zilog Z180
z80	Add support for Zilog Z80
z80n	Add support for Zilog Z80N

urjtag

Flag	Description
ftd2xx	Enable support for USB FTDI chips via <pkg>dev-embedded/libftd2xx</pkg>
readline

dev-libs

nanopb

Flag	Description
pb-malloc	Enable dynamic allocation support in the decoder

dev-util

claude-code

Flag	Description
cpu_flags_x86_avx
cpu_flags_x86_avx2

oh-my-pi-bin

Flag	Description
cpu_flags_x86_popcnt
cpu_flags_x86_sse3
cpu_flags_x86_sse4_1
cpu_flags_x86_sse4_2
elibc_glibc
elibc_musl

games-util

chiaki-ng

Flag	Description
cli	Build CLI interface
mbedtls	Use mbedtls instead of OpenSSL as part of Chiaki lib
sdl	Add support for touchpad and sensor handling via SDL. Adds support for any controller supported by SDL

media-fonts

kose-font

Flag	Description
mono	Monospace variant

lxgw-neo-zhisong

Flag	Description
plus	Plus variant (Supports Unicode CJK Unified Ideographs Extension A)

yozai-font

Flag	Description
light	Light weight variant
medium	Medium weight variant

media-gfx

netgen

Flag	Description
jpeg
opencascade	Enable OpenCASCADE support

media-libs

freetype-wps

Flag	Description
adobe-cff	Use Adobe CFF as default font-renderer
brotli
bzip2	Support bzip2 compressed PCF fonts.
cleartype-hinting	Bytecode hinting mode for TrueType fonts that activates subpixel hinting (a.k.a. ClearType hinting) by default
fontforge	Install internal headers required for TrueType debugger in <pkg>media-gfx/fontforge</pkg> (built with USE=truetype-debugger)
harfbuzz	Use <pkg>media-libs/harfbuzz</pkg> for auto-hinting OpenType fonts. WARNING: may trigger circular dependencies!
png
svg

openimageio

Flag	Description
${CPU_FEATURES[*]%:*}
dicom	Enable DICOM medical image file support via <pkg>sci-libs/dcmtk</pkg>
fits	Enable support for NASA's <pkg>sci-libs/cfitsio</pkg> library
gif
jpeg2k
jpegxl
libcxx	Build against <pkg>llvm-runtimes/libcxx</pkg> when using clang
opencv	Enable OpenCV support via <pkg>media-libs/opencv</pkg>
openvdb	Enable OpenVDB support via <pkg>media-gfx/openvdb</pkg>
ptex	Enable Ptex texture mapping system file support via <pkg>media-libs/ptex</pkg>
raw
truetype

openpgl

Flag	Description
"(
${X86_CPU_FLAGS[*]/#/cpu_flags_x86_}
(
)
)"
avx2
avx512dq
sse4_2

media-sound

audacity

Flag	Description
alsa
audiocom	Enable integrated uploading to audio.com
flac
id3tag	Enables ID3 tagging with id3tag library
ladspa
lv2	Add support for Ladspa V2
mpg123	Use <pkg>media-sound/mpg123</pkg> instead of <pkg>media-libs/libmad</pkg> for decoding MPEG decoding
ogg
opus
portmidi	Enable support for MIDI via <pkg>media-libs/portmidi</pkg>
portmixer	Enable the internal portmixer feature
portsmf	Enable support for Portable Standard Midi File Library
sbsms	Enables sbsms library support for slower, more accurate pitch and tempo changing
twolame	Enables twolame support (MPEG Audio Layer 2 encoder)
vamp	Enables vamp plugins support (Audio analysing plugins)
vorbis
vst	Enable VST plugin support
wavpack

media-video

uxplay

Flag	Description
vaapi

net-print

hpuld

Flag	Description
scanner	Enable scanner on multifunction devices which support it

net-proxy

mihomo

Flag	Description
gvisor	Enable gvisor stack support

net-wireless

uhd

Flag	Description
b100	support B100 hardware
b200	support B200, B210, B200mini, B205mini hardware
cpu_flags_arm_neon
e300	support E300, E310 hardware
mpmd	support N300, N310 hardware
octoclock	Octoclock Network Support
usrp1	support USRP1 hardware
usrp2	support USRP2, N200, N210 hardware
utils	utilities needed to list, query, calibrate, or update FPGA/Firmware
x300	support X300, X310 hardware

sci-electronics

kicad

Flag	Description
nls
openmp

kicad-meta

Flag	Description
minimal	Do not install extra data like 3D packages and templates.

opensta

Flag	Description
tclreadline	Enable TCL readline support for interactive command line editing

sby

Flag	Description
yices2	Enable Yices2 SMT solver support

surfer

Flag	Description
accesskit	Enable accessibility support via accesskit
performance-plot	Enable performance plotting with egui_plot
wasm-plugins	Enable WASM plugin support via extism

sci-libs

libsigrok

Flag	Description
$(ruby_get_use_targets)
bluetooth
cxx
gpib	Enable drivers that need <pkg>sci-libs/linux-gpib</pkg>
hidapi	Enable drivers that need <pkg>dev-libs/hidapi</pkg>
java
nettle	Enable drivers that need <pkg>dev-libs/nettle</pkg>
ruby

sci-mathematics

cado-nfs

Flag	Description
curl	Support fetching and pushing (requires webdav too) over http:// and https:// protocols
hwloc	Displays the hardware topology in convenient formats
mysql	Install mysql database to store data

mathematica

Flag	Description
R	Enable <pkg>dev-lang/R</pkg> backend support
bundle	Install from Wolfram's bundle file or from Mathematica only
mqtt	Enable MQTTLink support using <pkg>app-misc/mosquitto</pkg> (MQTT broker)

sys-fs

sanoid

Flag	Description
cron	Installs cron file

sys-libs

libnvidia-container

Flag	Description
seccomp

sys-process

nvtop

Flag	Description
unicode	Enable support for ncurses Unicode choice
video_cards_amdgpu
video_cards_freedreno
video_cards_intel
video_cards_nvidia

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