3dfxEnable support for Voodoo chipsets, also called as 3DFX and TDFX3
XAdd support for X11296
Xaw3dAdd support for the 3d athena widget set9
a52Enable support for decoding ATSC A/52 streams used in DVD7
aacEnable support for MPEG-4 AAC Audio25
aalibAdd support for media-libs/aalib (ASCII-Graphics Library)12
accessibilityAdd support for accessibility (eg 'at-spi' library)8
aclAdd support for Access Control Lists45
acpiAdd support for Advanced Configuration and Power Interface4
adnsAdd support for asynchronous DNS resolution5
afsAdd OpenAFS support (distributed file system)5
alsaAdd support for media-libs/alsa-lib (Advanced Linux Sound Architecture)144
altivecAdd support for optimizations for G4 and G5/ppc970 processors21
aoUse libao audio output library for sound playback16
apache2Add Apache2 support12
apmAdd APM (Advanced Power Management) support2
aquaInclude support for the Mac OS X Aqua (Carbon/Cocoa) GUI20
atmEnable Asynchronous Transfer Mode protocol support7
audiofileAdd support for libaudiofile where applicable8
auditEnable support for Linux audit subsystem using sys-process/audit18
avahiAdd avahi/Zeroconf support5
ayatanaBuild in support for Ayatana notification using the libindicate or libappindicator plugin12
bash-completionEnable bash-completion support5
berkdbAdd support for sys-libs/db (Berkeley DB for MySQL)40
bidiEnable bidirectional language support13
big-endianBig-endian toolchain support2
bindistFlag to enable or disable options for prebuilt (GRP) packages (eg. due to licensing issues)22
blasAdd support for the virtual/blas numerical library8
bluetoothEnable Bluetooth Support36
bootstrap!!internal use only!! DO NOT SET THIS FLAG YOURSELF!, used during original system bootstrapping [make stage2]2
brandingEnable Gentoo specific branding8
build!!internal use only!! DO NOT SET THIS FLAG YOURSELF!, used for creating build images and the first half of bootstrapping [make stage1]13
bzip2Use the bzlib compression library55
cairoEnable support for the cairo graphics library31
calendarAdd support for calendars (not using mcal!)6
cannaAdd support for the Canna kana to kanji conversion engine5
capsUse Linux capabilities library to control privilege35
cdbAdd support for the CDB database engine from the author of qmail3
cddaAdd Compact Disk Digital Audio (Standard Audio CD) support13
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 games12
cdparanoiaEnable cdparanoia (audio CD ripper) support4
cdrAdd support for CD writer hardware8
cgiAdd CGI script support11
cjkAdd support for Multi-byte character languages (Chinese, Japanese, Korean)22
clamavAdd support for Clam AntiVirus software (usually with a plugin)10
connmanAdd support for net-misc/connman5
coreaudioBuild the CoreAudio driver on Mac OS X systems7
cracklibSupport for cracklib strong password checking6
cryptAdd support for encryption -- using mcrypt or gpg where applicable56
cscopeEnable cscope interface -- in vim for example2
cssEnable reading of encrypted DVDs2
cupsAdd support for CUPS (Common Unix Printing System)34
curlAdd support for client-side URL transfer library59
custom-cflagsBuild with user-specified CFLAGS (unsupported)26
cvsEnable CVS (Concurrent Versions System) integration7
cxxBuild support for C++ (bindings, extra libraries, code generation, ...)30
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)93
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)72
dgaAdd DGA (Direct Graphic Access) support for X7
directfbAdd support for DirectFB layer (library for FB devices)1
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 globally1764
driEnable direct rendering: used for accelerated 3D and some 2D, like DMA4
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 DVDs11
dvdrAdd support for DVD writer hardware (e.g. in xcdroast)4
edsEnable support for Evolution-Data-Server (EDS)6
emacsAdd support for GNU Emacs92
embossAdd support for the European Molecular Biology Open Software Suite6
encodeAdd support for encoding of audio or video files6
enscriptAdd enscript support to colourize code stored in the repository1
evoAdd support for mail-client/evolution1
examplesInstall examples, usually source code842
exifAdd support for reading EXIF headers from JPEG and TIFF images28
expatEnable the use of dev-libs/expat for XML parsing13
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 support51
fftwUse FFTW library for computing Fourier transforms29
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 database8
flacAdd support for FLAC: Free Lossless Audio Codec57
fltkAdd support for the Fast Light Toolkit gui interface10
fontconfigSupport for configuring and customizing font access via media-libs/fontconfig9
foomaticdbAdd support for the foomatic printing driver database1
fortranAdd support for fortran36
freetdsAdd support for the TDS protocol to connect to MSSQL/Sybase databases3
freewnnAdd support for FreeWnn kana to kanji conversion engine4
ftpAdd FTP (File Transfer Protocol) support5
gcjEnable building with gcj (The GNU Compiler for the Javatm Programming Language)0
gdAdd support for media-libs/gd (to generate graphics on the fly)15
gdbmAdd support for sys-libs/gdbm (GNU database libraries)31
geoipAdd geoip support for country and city lookup based on IPs28
geolocationEnable physical position determination6
ggiAdd support for media-libs/libggi (non-X video api/drivers)4
gifAdd GIF image support41
gimpBuild a plugin for the GIMP9
gitEnable git (version control system) support15
glutBuild an OpenGL plugin using the GLUT library6
gmpAdd support for dev-libs/gmp (GNU MP library)26
gnomeAdd GNOME support57
gnome-keyringEnable support for storing passwords via gnome-keyring35
gnuplotEnable support for gnuplot (data and function plotting)10
gnutlsPrefer net-libs/gnutls as SSL/TLS provider (ineffective with USE=-ssl)72
gphoto2Add digital camera support9
gpmAdd support for sys-libs/gpm (Console-based mouse driver)29
gpsAdd support for Global Positioning System8
graphicsmagickBuild and link against GraphicsMagick instead of ImageMagick (might require USE=imagemagick if optional)11
graphvizAdd support for the Graphviz library12
gslUse the GNU scientific library for calculations17
gsmAdd support for the gsm lossy speech compression codec12
gstreamerAdd support for media-libs/gstreamer (Streaming media)40
gtkAdd support for x11-libs/gtk+ (The GIMP Toolkit)195
gtk-docBuild and install gtk-doc based developer documentation for dev-util/devhelp, IDE and offline use7
guileAdd support for the guile Scheme interpreter13
gzipCompress files with Lempel-Ziv coding (LZ77)5
handbookEnable handbooks generation for packages by KDE0
hardenedActivate default security enhancements for toolchain (gcc, glibc, binutils)34
hddtempEnable monitoring of hdd temperature (app-admin/hddtemp)7
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.10
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 library24
icqEnable ICQ IM protocol support2
icuEnable ICU (Internationalization Components for Unicode) support, using dev-libs/icu20
idnEnable support for Internationalized Domain Names35
ieee1394Enable FireWire/iLink IEEE1394 support (dv, camera, ...)11
imagemagickEnable optional support for the ImageMagick or GraphicsMagick image converter32
imapAdd support for IMAP (Internet Mail Application Protocol)1
imlibAdd support for imlib, an image loading and rendering library9
infinibandEnable Infiniband RDMA transport support6
inotifyEnable inotify filesystem monitoring support3
introspectionAdd support for GObject based introspection16
iodbcAdd support for iODBC library10
iosEnable support for Apple's iDevice with iOS operating system (iPad, iPhone, iPod, etc)5
ipodEnable support for iPod device access6
ipv6Add support for IP version 6237
jackAdd support for the JACK Audio Connection Kit81
javaAdd support for Java70
javascriptEnable javascript support11
jbigEnable jbig-kit support for tiff, Hylafax, ImageMagick, etc5
jemallocUse dev-libs/jemalloc for memory management20
jingleEnable voice calls for jabber2
jitEnable just-in-time compilation for improved performance. May prevent use of some PaX memory protection features in Gentoo Hardened.5
joystickAdd support for joysticks in all packages10
jpegAdd JPEG image support114
jpeg2kSupport for JPEG 2000, a wavelet-based image compression format34
kdeAdd support for KDE (K Desktop Environment)29
kerberosAdd kerberos support83
ladspaEnable the ability to support ladspa plugins8
lamePrefer using LAME libraries for MP3 encoding support11
lapackAdd support for the virtual/lapack numerical library20
lashAdd LASH Audio Session Handler support13
latexAdd support for LaTeX (typesetting package)22
lcmsAdd lcms support (color management engine)22
ldapAdd LDAP support (Lightweight Directory Access Protocol)100
libassSRT/SSA/ASS (SubRip / SubStation Alpha) subtitle support4
libavPrefer libav over ffmpeg whenever both are supported71
libcacaAdd support for colored ASCII-art graphics9
libeditUse the libedit library (replacement for readline)18
libffiEnable support for Foreign Function Interface library3
libnotifyEnable desktop notification support62
libresslUse dev-libs/libressl instead of dev-libs/openssl when applicable (see also the ssl useflag)370
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)22
livecd!!internal use only!! DO NOT SET THIS FLAG YOURSELF!, used during livecd building7
lm_sensorsAdd linux lm_sensors (hardware sensors) support11
luaEnable Lua scripting support51
luajitUse dev-lang/luajit instead of dev-lang/lua (ineffective with USE=-lua)28
lzmaSupport for LZMA (de)compression algorithm28
lzoEnable support for lzo compression19
m17n-libEnable m17n-lib support5
madAdd support for mad (high-quality mp3 decoder library and cli frontend)22
maildirAdd support for maildir (~/.maildir) style mail spools3
matroskaAdd support for the matroska container format (extensions .mkv, .mka and .mks)3
mboxAdd support for mbox (/var/spool/mail) style mail spools7
memcachedAdd support for memcached10
memlimitAdd memory usage limiting in supporting programs1
mhashAdd support for the mhash library4
migemoEnable migemo support for Japanese1
mikmodAdd libmikmod support to allow playing of SoundTracker-style music files10
milterAdd sendmail mail filter (milter) support2
mimeAdd MIME support1
minimalInstall a very minimal build (disables, for example, plugins, fonts, most drivers, non-critical features)174
mmapAdd mmap (memory map) support4
mmsSupport for Microsoft Media Server (MMS) streams9
mngAdd support for libmng (MNG images)10
modplugAdd libmodplug support for playing SoundTracker-style music files16
modulesBuild the kernel modules5
monoBuild Mono bindings to support dotnet type stuff11
motifAdd support for the Motif toolkit16
mp3Add support for reading mp3 files54
mp4Support for MP4 container format11
mpegAdd libmpeg3 support to various packages7
mpiAdd MPI (Message Passing Interface) layer to the apps that support it59
mplayerEnable mplayer support for playback or encoding7
msnEnable MSN Messenger IM protocol support3
mssqlAdd support for Microsoft SQL Server database8
mtpEnable support for Media Transfer Protocol8
muleAdd multi-language support to XEmacs2
multilibOn 64bit systems, if you want to be able to compile 32bit and 64bit binaries10
musepackEnable support for the musepack audio codec15
musicbrainzLookup audio metadata using MusicBrainz community service (
mysqlAdd mySQL Database support159
mysqliAdd support for the improved mySQL libraries3
nasAdd support for network audio sound13
ncursesAdd ncurses support (console display library)91
neXtEnable neXt toolkit3
neonEnable optimization support for ARM NEON processors15
netbootEnable network booting1
netcdfEnable NetCDF data format support9
networkmanagerEnable net-misc/networkmanager support18
nisSupport for NIS/YP services11
nlsAdd Native Language Support (using gettext - GNU locale utilities)560
nntpAdd support for newsgroups (Network News Transfer Protocol)6
nocdInstall all files required to run the application without a CD mounted3
nptlEnable support for Native POSIX Threads Library, the new threading module (requires linux-2.6 or better usually)0
nspluginBuild plugin for browsers supporting the Netscape plugin architecture (that is almost any modern browser)16
ocamlAdd support/bindings for the Ocaml language7
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)39
offensiveEnable potentially offensive items in packages15
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 Library25
openexrSupport for the OpenEXR graphics file format20
openglAdd support for OpenGL (3D graphics)158
openmpBuild support for the OpenMP (support parallel computing), requires >=sys-devel/gcc-4.2 built with USE="openmp"84
opusEnable Opus audio codec support26
oracleEnable Oracle Database support12
orcUse dev-lang/orc for just-in-time optimization of array operations0
oscEnable support for Open Sound Control9
oscarEnable Oscar (AIM/ICQ) IM protocol support3
ossAdd support for OSS (Open Sound System)89
pamAdd support for PAM (Pluggable Authentication Modules) - DANGEROUS to arbitrarily flip118
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 computers3
pcreAdd support for Perl Compatible Regular Expressions41
pdaAdd support for portable devices3
pdfAdd general support for PDF (Portable Document Format), this replaces the pdflib and cpdflib flags37
perlAdd optional support/bindings for the Perl language89
phpInclude support for the PHP language14
pieBuild programs as Position Independent Executables (a security hardening technique)3
plasmaBuild optional KDE plasma addons2
plotutilsAdd support for plotutils (library for 2-D vector graphics)2
pngAdd support for libpng (PNG images)113
policykitEnable PolicyKit authentication support23
portaudioAdd support for the crossplatform portaudio audio API28
posixAdd support for POSIX-compatible functions2
postgresAdd support for the postgresql database153
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
preludeAdd support/bindings for the Prelude Intrusion Detection System2
profileAdd support for software performance analysis (will likely vary from ebuild to ebuild)16
pulseaudioAdd support for PulseAudio sound server113
pythonAdd optional support/bindings for the Python language232
qdbmAdd support for the qdbm (Quick Database Manager) library3
qmail-sppAdd support for qmail SMTP plugins3
qt4Add support for the Qt GUI/Application Toolkit version 4.x0
qt5Add support for the Qt 5 application and UI framework80
quicktimeAdd support for OpenQuickTime4
radiusAdd support for RADIUS authentication10
rawAdd support for raw image formats15
rdpEnables RDP/Remote Desktop support4
readlineEnable support for libreadline, a GNU line-editing library that almost everyone wants103
recodeEnable support for the GNU recode library2
rssEnable support for RSS feeds8
rubyAdd support/bindings for the Ruby language40
sambaAdd support for SAMBA (Windows File and Printer sharing)38
saslAdd support for the Simple Authentication and Security Layer56
savedconfigUse this to restore your config from /etc/portage/savedconfig ${CATEGORY}/${PN}. Make sure your USE flags allow for appropriate dependencies8
scannerAdd support for scanner hardware (e.g. build the sane frontend in kdegraphics)13
sctpSupport for Stream Control Transmission Protocol7
sdlAdd support for Simple Direct Layer (media library)75
seamonkeyAdd support for the Seamonkey web-browser1
seccompEnable seccomp (secure computing mode) to perform system call filtering at runtime to increase security of programs22
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
shortenAdd support for the shorten audio compressor1
skeyEnable S/Key (Single use password) authentication support4
slangAdd support for the slang text display library (it's like ncurses, but different)11
slpAdd Service Locator Protocol support3
smartcardEnable smartcard support14
smpEnable support for multiprocessors or multicore systems7
sndfileAdd support for libsndfile26
snmpAdd support for the Simple Network Management Protocol if available34
soapAdd support for SOAP (Simple Object Access Protocol)4
socketsAdd support for tcp/ip sockets4
socks5Add support for the socks5 proxy13
soundEnable sound support17
sourceZip the sources and install them33
soxAdd support for Sound eXchange (SoX)7
speexAdd support for the speex audio codec (used for speech)20
spellAdd dictionary support46
sqliteAdd support for sqlite - embedded sql database116
sslAdd support for SSL/TLS connections (Secure Socket Layer / Transport Layer Security)276
startup-notificationEnable application startup event feedback mechanism16
static!!do not set this during bootstrap!! Causes binaries to be statically linked instead of dynamically164
static-libsBuild static versions of dynamic libraries as well1243
subversionEnable subversion (version control system) support16
suidEnable setuid root program, with potential security risks18
svgAdd support for SVG (Scalable Vector Graphics)44
svgaAdd support for SVGAlib (graphics library)13
sybaseAdd support for the Sybase SQL Database Server1
symlinkForce kernel ebuilds to automatically update the /usr/src/linux symlink7
syslogEnable support for syslog19
systemdEnable use of systemd-specific libraries and features like socket activation or session tracking119
szipUse the szip compression library5
taglibEnable tagging support with taglib16
tclAdd support the Tcl language44
tcmallocUse the dev-util/google-perftools libraries to replace the malloc() implementation with a possibly faster one12
tcpdAdd support for TCP wrappers49
testEnable dependencies and/or preparations necessary to run tests (usually controlled by FEATURES=test but can be toggled independently)3147
theoraAdd support for the Theora Video Compression Codec20
threadsAdd threads support for various packages. Usually pthreads133
tidyAdd support for HTML Tidy3
tiffAdd support for the TIFF image format75
timidityBuild with Timidity++ (MIDI sequencer) support7
tkAdd support for Tk GUI toolkit64
truetypeAdd support for FreeType and/or FreeType2 fonts66
uclibcEnable uclibc specific patches and build or link uclibc2
udevEnable virtual/udev integration (device discovery, power and storage device support, etc)34
udisksEnable storage management support (automounting, volume monitoring, etc)9
unicodeAdd support for Unicode81
unwindAdd support for call stack unwinding and function name resolution11
upnpEnable UPnP port mapping support21
upnp-avEnable UPnP audio/video streaming support4
upowerEnable power management support8
usbAdd USB support to applications that have optional USB support (e.g. cups)36
v4lEnable support for video4linux (using linux-headers or userspace libv4l libraries)33
vaapiEnable Video Acceleration API for hardware decoding16
valaEnable bindings for dev-lang/vala51
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 interface16
vhostsAdd support for installing web-based applications into a virtual-hosting environment4
videosInstall optional video files (used in some games)8
vim-syntaxPulls in related vim syntax scripts44
vncEnable VNC (remote desktop viewer) support11
vorbisAdd support for the OggVorbis audio codec76
wavpackAdd support for wavpack audio compression tools19
waylandEnable dev-libs/wayland backend45
webkitAdd support for the WebKit HTML rendering/layout engine26
webpAdd support for the WebP image format28
wifiEnable wireless network functions9
wmfAdd support for the Windows Metafile vector image format6
wxwidgetsAdd support for wxWidgets/wxGTK GUI toolkit17
x264Enable h264 encoding using x26412
xattrAdd support for extended attributes (filesystem-stored metadata)28
xcbSupport the X C-language Binding, a replacement for Xlib2
xcompositeEnable support for the Xorg composite extension2
xemacsAdd support for XEmacs4
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)15
xineAdd support for the XINE movie libraries6
xineramaAdd support for querying multi-monitor screen geometry through the Xinerama API52
xinetdAdd support for the xinetd super-server21
xmlAdd support for XML files58
xmlrpcSupport for xml-rpc library5
xmpEnable support for Extensible Metadata Platform (Adobe XMP)9
xmppEnable support for Extensible Messaging and Presence Protocol (XMPP) formerly known as Jabber9
xosdSends display using the X On Screen Display library4
xpmAdd support for XPM graphics format18
xscreensaverAdd support for XScreenSaver extension6
xvAdd in optional support for the Xvideo extension (an X API for video playback)12
xvidAdd support for's open-source mpeg-4 codec9
yahooEnable Yahoo Messenger IM protocol support3
yazAdd in optional support for the Z39.50 Protocol for Information Retrieval (YAZ)1
zeroconfSupport for DNS Service Discovery (DNS-SD)44
zipEnable support for ZIP archives11
zlibAdd support for zlib (de)compression133
zsh-completionEnable zsh completion support21