3dfxEnable support for Voodoo chipsets, also called as 3DFX and TDFX1
XAdd support for X11284
Xaw3dAdd support for the 3d athena widget set7
a52Enable support for decoding ATSC A/52 streams used in DVD8
aacEnable support for MPEG-4 AAC Audio23
aalibAdd support for media-libs/aalib (ASCII-Graphics Library)12
accessibilityAdd support for accessibility (eg 'at-spi' library)8
aclAdd support for Access Control Lists43
acpiAdd support for Advanced Configuration and Power Interface3
adnsAdd support for asynchronous DNS resolution2
afsAdd OpenAFS support (distributed file system)5
alsaAdd support for media-libs/alsa-lib (Advanced Linux Sound Architecture)134
altivecAdd support for optimizations for G4 and G5/ppc970 processors18
aoUse libao audio output library for sound playback16
apache2Add Apache2 support10
aquaInclude support for the Mac OS X Aqua (Carbon/Cocoa) GUI20
atmEnable Asynchronous Transfer Mode protocol support2
appindicatorBuild in support for notifications using the libindicate or libappindicator plugin18
audiofileAdd support for libaudiofile where applicable8
auditEnable support for Linux audit subsystem using sys-process/audit16
ayatanaBuild in support for Ayatana notification using the libindicate or libappindicator plugin2
bash-completionEnable bash-completion support5
berkdbAdd support for sys-libs/db (Berkeley DB for MySQL)36
bidiEnable bidirectional language support13
big-endianBig-endian toolchain support4
bindistFlag to enable or disable options for prebuilt (GRP) packages (eg. due to licensing issues)20
blasAdd support for the virtual/blas numerical library9
bluetoothEnable Bluetooth Support33
brandingEnable Gentoo specific branding9
build!!internal use only!! DO NOT SET THIS FLAG YOURSELF!, used for creating build images and the first half of bootstrapping [make stage1]8
bzip2Use the bzlib compression library58
cairoEnable support for the cairo graphics library27
calendarAdd support for calendars (not using mcal!)6
cannaAdd support for the Canna kana to kanji conversion engine5
capsUse Linux capabilities library to control privilege36
cdbAdd support for the CDB database engine from the author of qmail3
cddaAdd Compact Disk Digital Audio (Standard Audio CD) support16
cddbAccess cddb servers to retrieve and submit information about compact disks10
cdinstallCopy files from the CD rather than asking the user to copy them, mostly used with games9
cdrAdd support for CD writer hardware10
cgiAdd CGI script support10
cjkAdd support for Multi-byte character languages (Chinese, Japanese, Korean)21
clamavAdd support for Clam AntiVirus software (usually with a plugin)10
colordSupport color management using x11-misc/colord7
connmanAdd support for net-misc/connman4
coreaudioBuild the CoreAudio driver on Mac OS X systems6
cracklibSupport for cracklib strong password checking6
cryptAdd support for encryption -- using mcrypt or gpg where applicable47
cssEnable reading of encrypted DVDs1
cupsAdd support for CUPS (Common Unix Printing System)36
curlAdd support for client-side URL transfer library58
custom-cflagsBuild with user-specified CFLAGS (unsupported)23
cvsEnable CVS (Concurrent Versions System) integration4
cxxBuild support for C++ (bindings, extra libraries, code generation, ...)26
dbiEnable dev-db/libdbi (database-independent abstraction layer) support8
dbmAdd support for generic DBM databases2
dbusEnable dbus support for anything that needs it (gpsd, gnomemeeting, etc)89
debugEnable extra debug codepaths, like asserts and extra output. If you want to get meaningful backtraces see
dedicatedAdd support for dedicated game servers (some packages do not provide clients and servers at the same time)27
dgaAdd DGA (Direct Graphic Access) support for X6
djvuSupport DjVu, a PDF-like document format esp. suited for scanned documents10
docAdd extra documentation (API, Javadoc, etc). It is recommended to enable per package instead of globally1517
driEnable direct rendering: used for accelerated 3D and some 2D, like DMA2
dtsEnable DTS Coherent Acoustics decoder support6
dvEnable support for a codec used by many camcorders5
dvbAdd support for DVB (Digital Video Broadcasting)9
dvdAdd support for DVDs8
dvdrAdd support for DVD writer hardware (e.g. in xcdroast)4
edsEnable support for Evolution-Data-Server (EDS)7
elogindEnable session tracking via sys-auth/elogind38
emacsAdd support for GNU Emacs85
embossAdd support for the European Molecular Biology Open Software Suite6
encodeAdd support for encoding of audio or video files5
examplesInstall examples, usually source code704
exifAdd support for reading EXIF headers from JPEG and TIFF images28
expatEnable the use of dev-libs/expat for XML parsing14
famEnable FAM (File Alteration Monitor) support11
fastcgiAdd support for the FastCGI interface8
fbconAdd framebuffer support for the console, via the kernel19
ffmpegEnable ffmpeg/libav-based audio/video codec support49
fftwUse FFTW library for computing Fourier transforms27
filecapsUse Linux file capabilities to control privilege rather than set*id (this is orthogonal to USE=caps which uses capabilities at runtime e.g. libcap)0
firebirdAdd support for the Firebird relational database7
flacAdd support for FLAC: Free Lossless Audio Codec56
fltkAdd support for the Fast Light Toolkit gui interface7
fontconfigSupport for configuring and customizing font access via media-libs/fontconfig8
fortranAdd support for fortran35
freetdsAdd support for the TDS protocol to connect to MSSQL/Sybase databases2
freewnnAdd support for FreeWnn kana to kanji conversion engine3
ftpAdd FTP (File Transfer Protocol) support4
gdAdd support for media-libs/gd (to generate graphics on the fly)13
gdbmAdd support for sys-libs/gdbm (GNU database libraries)26
geoipAdd geoip support for country and city lookup based on IPs29
geolocationEnable physical position determination8
ggiAdd support for media-libs/libggi (non-X video api/drivers)3
gifAdd GIF image support36
gimpBuild a plugin for the GIMP9
gitEnable git (version control system) support12
gles2-onlyUse GLES 2.0 or later instead of full OpenGL24
glutBuild an OpenGL plugin using the GLUT library7
gmpAdd support for dev-libs/gmp (GNU MP library)27
gnomeAdd GNOME support45
gnome-keyringEnable support for storing passwords via gnome-keyring28
gnuplotEnable support for gnuplot (data and function plotting)8
gnutlsPrefer net-libs/gnutls as SSL/TLS provider (ineffective with USE=-ssl)71
gphoto2Add digital camera support7
gpmAdd support for sys-libs/gpm (Console-based mouse driver)26
gpsAdd support for Global Positioning System6
graphicsmagickBuild and link against GraphicsMagick instead of ImageMagick (requires USE=imagemagick if optional)14
graphvizAdd support for the Graphviz library11
gslUse the GNU scientific library for calculations15
gsmAdd support for the gsm lossy speech compression codec6
gstreamerAdd support for media-libs/gstreamer (Streaming media)37
gtkAdd support for x11-libs/gtk+ (The GIMP Toolkit)166
gtk-docBuild and install gtk-doc based developer documentation for dev-util/devhelp, IDE and offline use59
guiEnable support for a graphical user interface20
guileAdd support for the guile Scheme interpreter11
gzipCompress files with Lempel-Ziv coding (LZ77)5
handbookEnable handbooks generation for packages by KDE0
hardenedActivate default security enhancements for toolchain (gcc, glibc, binutils)31
hddtempEnable monitoring of hdd temperature (app-admin/hddtemp)5
hdf5Add support for the Hierarchical Data Format v523
headers-onlyInstall only C headers instead of whole package. Mainly used by sys-devel/crossdev for toolchain bootstrap.6
hscolourInclude coloured haskell sources to generated documentation (dev-haskell/hscolour)0
ibmAdd support for IBM ppc64 specific systems4
iconvEnable support for the iconv character set conversion library23
icuEnable ICU (Internationalization Components for Unicode) support, using dev-libs/icu21
idnEnable support for Internationalized Domain Names34
ieee1394Enable FireWire/iLink IEEE1394 support (dv, camera, ...)9
imagemagickEnable optional support for the ImageMagick or GraphicsMagick image converter24
imapAdd support for IMAP (Internet Mail Application Protocol)1
imlibAdd support for imlib, an image loading and rendering library8
infinibandEnable Infiniband RDMA transport support6
inotifyEnable inotify filesystem monitoring support2
introspectionAdd support for GObject based introspection24
iodbcAdd support for iODBC library10
iosEnable support for Apple's iDevice with iOS operating system (iPad, iPhone, iPod, etc)4
ipodEnable support for iPod device access4
ipv6Add support for IP version 6208
jackAdd support for the JACK Audio Connection Kit78
javaAdd support for Java66
javascriptEnable javascript support11
jbigEnable jbig-kit support for tiff, Hylafax, ImageMagick, etc5
jemallocUse dev-libs/jemalloc for memory management19
jitEnable just-in-time compilation for improved performance. May prevent use of some PaX memory protection features in Gentoo Hardened.6
joystickAdd support for joysticks in all packages8
jpegAdd JPEG image support109
jpeg2kSupport for JPEG 2000, a wavelet-based image compression format16
kdeAdd support for software made by KDE, a free software community27
kerberosAdd kerberos support74
ladspaEnable the ability to support ladspa plugins9
lamePrefer using LAME libraries for MP3 encoding support10
lapackAdd support for the virtual/lapack numerical library20
lashAdd LASH Audio Session Handler support13
latexAdd support for LaTeX (typesetting package)21
lcmsAdd lcms support (color management engine)23
ldapAdd LDAP support (Lightweight Directory Access Protocol)97
libassSRT/SSA/ASS (SubRip / SubStation Alpha) subtitle support5
libavPrefer libav over ffmpeg whenever both are supported3
libcacaAdd support for colored ASCII-art graphics8
libeditUse the libedit library (replacement for readline)18
libffiEnable support for Foreign Function Interface library3
libnotifyEnable desktop notification support54
libresslUse dev-libs/libressl instead of dev-libs/openssl when applicable (see also the ssl useflag)377
libsamplerateBuild with support for converting sample rates using libsamplerate19
libwwwAdd libwww support (General purpose WEB API)2
lircAdd support for lirc (Linux's Infra-Red Remote Control)19
livecd!!internal use only!! DO NOT SET THIS FLAG YOURSELF!, used during livecd building6
lm-sensorsAdd linux lm-sensors (hardware sensors) support10
luaEnable Lua scripting support55
luajitUse dev-lang/luajit instead of dev-lang/lua (ineffective with USE=-lua)28
lzmaSupport for LZMA (de)compression algorithm33
lz4Enable support for lz4 compression (as implemented in app-arch/lz4)20
lzoEnable support for lzo compression21
m17n-libEnable m17n-lib support4
madAdd support for mad (high-quality mp3 decoder library and cli frontend)24
magicAdd support for file type detection via magic bytes (usually via libmagic from sys-apps/file)4
maildirAdd support for maildir (~/.maildir) style mail spools3
matroskaAdd support for the matroska container format (extensions .mkv, .mka and .mks)2
mboxAdd support for mbox (/var/spool/mail) style mail spools6
memcachedAdd support for memcached10
mhashAdd support for the mhash library4
mikmodAdd libmikmod support to allow playing of SoundTracker-style music files10
milterAdd sendmail mail filter (milter) support2
minimalInstall a very minimal build (disables, for example, plugins, fonts, most drivers, non-critical features)168
mmapAdd mmap (memory map) support4
mmsSupport for Microsoft Media Server (MMS) streams10
mngAdd support for libmng (MNG images)9
modplugAdd libmodplug support for playing SoundTracker-style music files17
modulesBuild the kernel modules4
monoBuild Mono bindings to support dotnet type stuff11
motifAdd support for the Motif toolkit14
mp3Add support for reading mp3 files52
mp4Support for MP4 container format10
mpegAdd libmpeg3 support to various packages7
mpiAdd MPI (Message Passing Interface) layer to the apps that support it63
mplayerEnable mplayer support for playback or encoding7
mssqlAdd support for Microsoft SQL Server database7
mtpEnable support for Media Transfer Protocol9
multilibOn 64bit systems, if you want to be able to compile 32bit and 64bit binaries9
musepackEnable support for the musepack audio codec14
musicbrainzLookup audio metadata using MusicBrainz community service (
mysqlAdd mySQL Database support143
mysqliAdd support for the improved mySQL libraries3
nasAdd support for network audio sound13
ncursesAdd ncurses support (console display library)89
neXtEnable neXt toolkit3
neonEnable optimization support for ARM NEON processors8
netcdfEnable NetCDF data format support11
networkmanagerEnable net-misc/networkmanager support16
nisSupport for NIS/YP services6
nlsAdd Native Language Support (using gettext - GNU locale utilities)520
nntpAdd support for newsgroups (Network News Transfer Protocol)5
nocdInstall all files required to run the application without a CD mounted2
nspluginBuild plugin for browsers supporting the Netscape plugin architecture (that is almost any modern browser)14
ocamlAdd support/bindings for the Ocaml language6
ocamloptEnable ocamlopt support (ocaml native code compiler) -- Produces faster programs (Warning: you have to disable/enable it at a global scale)0
oci8Add Oracle 8 Database Support4
oci8-instant-clientUse dev-db/oracle-instantclient-basic as Oracle provider instead of requiring a full Oracle server install2
odbcAdd ODBC Support (Open DataBase Connectivity)35
offensiveEnable potentially offensive items in packages10
ofxEnable support for importing (and exporting) OFX (Open Financial eXchange) data files5
oggAdd support for the Ogg container format (commonly used by Vorbis, Theora and flac)19
openalAdd support for the Open Audio Library23
openexrSupport for the OpenEXR graphics file format21
openglAdd support for OpenGL (3D graphics)118
openmpBuild support for the OpenMP (support parallel computing), requires >=sys-devel/gcc-4.2 built with USE="openmp"87
opusEnable Opus audio codec support28
oracleEnable Oracle Database support10
orcUse dev-lang/orc for just-in-time optimization of array operations0
oscEnable support for Open Sound Control10
ossAdd support for OSS (Open Sound System)83
pamAdd support for PAM (Pluggable Authentication Modules) - DANGEROUS to arbitrarily flip108
pchEnable precompiled header support for faster compilation at the expense of disk space and memory (>=sys-devel/gcc-3.4 only)13
pcmciaAdd support for PCMCIA slots/devices found on laptop computers2
pcreAdd support for Perl Compatible Regular Expressions43
pdaAdd support for portable devices3
pdfAdd general support for PDF (Portable Document Format), this replaces the pdflib and cpdflib flags34
perlAdd optional support/bindings for the Perl language82
phpInclude support for the PHP language13
pieBuild programs as Position Independent Executables (a security hardening technique)3
plasmaBuild optional KDE plasma addons4
plotutilsAdd support for plotutils (library for 2-D vector graphics)2
pngAdd support for libpng (PNG images)108
policykitEnable PolicyKit authentication support25
portaudioAdd support for the crossplatform portaudio audio API28
posixAdd support for POSIX-compatible functions3
postgresAdd support for the postgresql database140
postscriptEnable support for the PostScript language (often with ghostscript-gpl or libspectre)20
ppdsAdd support for automatically generated ppd (printing driver) files1
prefixDefines if a Gentoo Prefix offset installation is used6
profileAdd support for software performance analysis (will likely vary from ebuild to ebuild)19
pulseaudioAdd support for PulseAudio sound server113
pythonAdd optional support/bindings for the Python language206
qdbmAdd support for the qdbm (Quick Database Manager) library3
qmail-sppAdd support for qmail SMTP plugins2
qt5Add support for the Qt 5 application and UI framework86
quicktimeAdd support for OpenQuickTime4
radiusAdd support for RADIUS authentication13
rawAdd support for raw image formats18
rdpEnables RDP/Remote Desktop support6
readlineEnable support for libreadline, a GNU line-editing library that almost everyone wants97
recodeEnable support for the GNU recode library2
rssEnable support for RSS feeds7
rubyAdd support/bindings for the Ruby language39
sambaAdd support for SAMBA (Windows File and Printer sharing)35
saslAdd support for the Simple Authentication and Security Layer50
savedconfigUse this to restore your config from /etc/portage/savedconfig ${CATEGORY}/${PN}. Make sure your USE flags allow for appropriate dependencies12
scannerAdd support for scanner hardware (e.g. build the sane frontend in kdegraphics)12
sctpSupport for Stream Control Transmission Protocol10
sdlAdd support for Simple Direct Layer (media library)69
seccompEnable seccomp (secure computing mode) to perform system call filtering at runtime to increase security of programs24
selinux!!internal use only!! Security Enhanced Linux support, this must be set by the selinux profile or breakage will occur237
semantic-desktopCross-KDE support for semantic search and information retrieval8
sessionAdd persistent session support9
skeyEnable S/Key (Single use password) authentication support3
slangAdd support for the slang text display library (it's like ncurses, but different)12
slpAdd Service Locator Protocol support2
smartcardEnable smartcard support13
smpEnable support for multiprocessors or multicore systems4
snappyEnable support for Snappy compression (as implemented in app-arch/snappy)5
sndfileAdd support for libsndfile27
snmpAdd support for the Simple Network Management Protocol if available32
soapAdd support for SOAP (Simple Object Access Protocol)3
socketsAdd support for tcp/ip sockets4
socks5Add support for the socks5 proxy12
soundEnable sound support17
sourceZip the sources and install them31
soxAdd support for Sound eXchange (SoX)7
speexAdd support for the speex audio codec (used for speech)19
spellAdd dictionary support46
split-usrEnable behavior to support maintaining /bin, /lib*, /sbin and /usr/sbin separately from /usr/bin and /usr/lib*8
sqliteAdd support for sqlite - embedded sql database109
sslAdd support for SSL/TLS connections (Secure Socket Layer / Transport Layer Security)244
startup-notificationEnable application startup event feedback mechanism16
static!!do not set this during bootstrap!! Causes binaries to be statically linked instead of dynamically150
static-libsBuild static versions of dynamic libraries as well1118
subversionEnable subversion (version control system) support13
suidEnable setuid root program, with potential security risks19
svgAdd support for SVG (Scalable Vector Graphics)39
svgaAdd support for SVGAlib (graphics library)12
symlinkForce kernel ebuilds to automatically update the /usr/src/linux symlink6
syslogEnable support for syslog17
systemdEnable use of systemd-specific libraries and features like socket activation or session tracking150
szipUse the szip compression library6
taglibEnable tagging support with taglib17
tclAdd support the Tcl language39
tcmallocUse the dev-util/google-perftools libraries to replace the malloc() implementation with a possibly faster one12
tcpdAdd support for TCP wrappers44
telemetrySend anonymized usage information to upstream so they can better understand our users9
testEnable dependencies and/or preparations necessary to run tests (usually controlled by FEATURES=test but can be toggled independently)2999
theoraAdd support for the Theora Video Compression Codec18
threadsAdd threads support for various packages. Usually pthreads122
tidyAdd support for HTML Tidy2
tiffAdd support for the TIFF image format71
timidityBuild with Timidity++ (MIDI sequencer) support6
tkAdd support for Tk GUI toolkit59
truetypeAdd support for FreeType and/or FreeType2 fonts61
uclibcEnable uclibc specific patches and build or link uclibc2
udevEnable virtual/udev integration (device discovery, power and storage device support, etc)35
udisksEnable storage management support (automounting, volume monitoring, etc)10
unicodeAdd support for Unicode78
unwindAdd support for call stack unwinding and function name resolution13
upnpEnable UPnP port mapping support20
upnp-avEnable UPnP audio/video streaming support3
upowerEnable power management support10
usbAdd USB support to applications that have optional USB support (e.g. cups)30
v4lEnable support for video4linux (using linux-headers or userspace libv4l libraries)28
vaapiEnable Video Acceleration API for hardware decoding18
valaEnable bindings for dev-lang/vala41
vanillaDo not add extra patches which change default behaviour; DO NOT USE THIS ON A GLOBAL SCALE as the severity of the meaning changes drastically21
vcdVideo CD support7
vdpauEnable the Video Decode and Presentation API for Unix acceleration interface17
vhostsAdd support for installing web-based applications into a virtual-hosting environment3
videosInstall optional video files (used in some games)7
vim-syntaxPulls in related vim syntax scripts42
vncEnable VNC (remote desktop viewer) support10
vorbisAdd support for the OggVorbis audio codec72
wavpackAdd support for wavpack audio compression tools19
waylandEnable dev-libs/wayland backend58
webkitAdd support for the WebKit HTML rendering/layout engine26
webpAdd support for the WebP image format29
wifiEnable wireless network functions9
wmfAdd support for the Windows Metafile vector image format6
wxwidgetsAdd support for wxWidgets/wxGTK GUI toolkit17
x264Enable h264 encoding using x26411
xattrAdd support for extended attributes (filesystem-stored metadata)27
xcbSupport the X C-language Binding, a replacement for Xlib1
xcompositeEnable support for the Xorg composite extension1
xemacsAdd support for XEmacs3
xfaceAdd xface support used to allow a small image of xface format to be included in an email via the header 'X-Face'6
xftBuild with support for XFT font renderer (x11-libs/libXft)14
xineAdd support for the XINE movie libraries6
xineramaAdd support for querying multi-monitor screen geometry through the Xinerama API51
xinetdAdd support for the xinetd super-server17
xmlAdd support for XML files54
xmlrpcSupport for xml-rpc library5
xmpEnable support for Extensible Metadata Platform (Adobe XMP)7
xmppEnable support for Extensible Messaging and Presence Protocol (XMPP) formerly known as Jabber8
xosdSends display using the X On Screen Display library3
xpmAdd support for XPM graphics format16
xscreensaverAdd support for XScreenSaver extension5
xvAdd in optional support for the Xvideo extension (an X API for video playback)11
xvidAdd support for's open-source mpeg-4 codec7
zeroconfSupport for DNS Service Discovery (DNS-SD)48
zipEnable support for ZIP archives12
zlibAdd support for zlib (de)compression131
zsh-completionEnable zsh completion support14
zstdEnable support for ZSTD compression18