| USE-Flag | Description | used |
|---|
| X | Add support for X11 | 397 |
| Xaw3d | Add support for the 3d athena widget set | 8 |
| a52 | Enable support for decoding ATSC A/52 streams used in DVD | 7 |
| aac | Enable support for MPEG-4 AAC Audio | 19 |
| aalib | Add support for media-libs/aalib (ASCII-Graphics Library) | 8 |
| accessibility | Add support for accessibility (eg 'at-spi' library) | 13 |
| acl | Add support for Access Control Lists | 35 |
| acpi | Add support for Advanced Configuration and Power Interface | 2 |
| adns | Add support for asynchronous DNS resolution | 1 |
| afs | Add OpenAFS support (distributed file system) | 5 |
| alsa | Add support for media-libs/alsa-lib (Advanced Linux Sound Architecture) | 132 |
| ao | Use libao audio output library for sound playback | 13 |
| apache2 | Add Apache2 support | 10 |
| aqua | Include support for the Mac OS X Aqua (Carbon/Cocoa) GUI | 17 |
| asm | Enable using assembly for optimization | 3 |
| atm | Enable Asynchronous Transfer Mode protocol support | 2 |
| apparmor | Enable support for the AppArmor application security system | 16 |
| appindicator | Build in support for notifications using the libindicate or libappindicator plugin | 16 |
| audiofile | Add support for libaudiofile where applicable | 6 |
| audit | Enable support for Linux audit subsystem using sys-process/audit | 21 |
| avif | Add AV1 Image Format (AVIF) support | 13 |
| bash-completion | Enable bash-completion support | 4 |
| berkdb | Add support for sys-libs/db (Berkeley DB) | 37 |
| bidi | Enable bidirectional language support | 11 |
| big-endian | Big-endian toolchain support | 12 |
| bindist | Flag to enable or disable options for prebuilt (GRP) packages (eg. due to licensing issues) | 6 |
| blas | Add support for the virtual/blas numerical library | 8 |
| bluetooth | Enable Bluetooth Support | 36 |
| branding | Enable Gentoo specific branding | 9 |
| brotli | Enable Brotli compression support | 18 |
| build | !!internal use only!! DO NOT SET THIS FLAG YOURSELF!, used for creating build images and the first half of bootstrapping [make stage1] | 6 |
| bzip2 | Enable bzip2 compression support | 55 |
| cairo | Enable support for the cairo graphics library | 21 |
| calendar | Add support for calendars (not using mcal!) | 7 |
| caps | Use Linux capabilities library to control privilege | 35 |
| cdb | Add support for the CDB database engine from the author of qmail | 5 |
| cdda | Add Compact Disk Digital Audio (Standard Audio CD) support | 14 |
| cddb | Access cddb servers to retrieve and submit information about compact disks | 7 |
| cdinstall | Copy files from the CD rather than asking the user to copy them, mostly used with games | 6 |
| cdr | Add support for CD writer hardware | 10 |
| cgi | Add CGI script support | 8 |
| cjk | Add support for Multi-byte character languages (Chinese, Japanese, Korean) | 16 |
| clamav | Add support for Clam AntiVirus software (usually with a plugin) | 9 |
| colord | Support color management using x11-misc/colord | 8 |
| connman | Add support for net-misc/connman | 3 |
| coreaudio | Build the CoreAudio driver on Mac OS X systems | 8 |
| cracklib | Support for cracklib strong password checking | 7 |
| crypt | Add support for encryption -- using mcrypt or gpg where applicable | 39 |
| css | Enable reading of encrypted DVDs | 0 |
| cuda | Enable NVIDIA CUDA support (computation on GPU) | 43 |
| cups | Add support for CUPS (Common Unix Printing System) | 32 |
| curl | Add support for client-side URL transfer library | 60 |
| custom-cflags | Build with user-specified CFLAGS (unsupported) | 31 |
| cvs | Enable CVS (Concurrent Versions System) integration | 3 |
| cxx | Build support for C++ (bindings, extra libraries, code generation, ...) | 17 |
| dbi | Enable dev-db/libdbi (database-independent abstraction layer) support | 7 |
| dbm | Add support for generic DBM databases | 1 |
| dbus | Enable dbus support for anything that needs it (gpsd, gnomemeeting, etc) | 93 |
| debug | Enable extra debug codepaths, like asserts and extra output. If you want to get meaningful backtraces see https://wiki.gentoo.org/wiki/Project:Quality_Assurance/Backtraces | 842 |
| dedicated | Add support for dedicated game servers (some packages do not provide clients and servers at the same time) | 21 |
| dga | Add DGA (Direct Graphic Access) support for X | 1 |
| dist-kernel | Enable subslot rebuilds on Distribution Kernel upgrades | 3 |
| djvu | Support DjVu, a PDF-like document format esp. suited for scanned documents | 9 |
| doc | Add extra documentation (API, Javadoc, etc). It is recommended to enable per package instead of globally | 1185 |
| dri | Enable direct rendering: used for accelerated 3D and some 2D, like DMA | 3 |
| dts | Enable DTS Coherent Acoustics decoder support | 5 |
| dv | Enable support for a codec used by many camcorders | 3 |
| dvb | Add support for DVB (Digital Video Broadcasting) | 9 |
| dvd | Add support for DVDs | 7 |
| dvdr | Add support for DVD writer hardware (e.g. in xcdroast) | 2 |
| eds | Enable support for Evolution-Data-Server (EDS) | 6 |
| egl | Enable EGL (Embedded-System Graphics Library, interfacing between windowing system and OpenGL/GLES) support | 8 |
| elogind | Enable session tracking via sys-auth/elogind | 43 |
| emacs | Add support for GNU Emacs | 84 |
| emboss | Add support for the European Molecular Biology Open Software Suite | 5 |
| encode | Add support for encoding of audio or video files | 4 |
| examples | Install examples, usually source code | 560 |
| exif | Add support for reading EXIF headers from JPEG and TIFF images | 29 |
| expat | Enable the use of dev-libs/expat for XML parsing | 12 |
| fam | Enable FAM (File Alteration Monitor) support | 7 |
| fastcgi | Add support for the FastCGI interface | 4 |
| fbcon | Add framebuffer support for the console, via the kernel | 14 |
| ffmpeg | Enable ffmpeg/libav-based audio/video codec support | 54 |
| fftw | Use FFTW library for computing Fourier transforms | 22 |
| filecaps | Use 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 |
| firebird | Add support for the Firebird relational database | 6 |
| flac | Add support for FLAC: Free Lossless Audio Codec | 53 |
| fltk | Add support for the Fast Light Toolkit gui interface | 6 |
| fontconfig | Support for configuring and customizing font access via media-libs/fontconfig | 10 |
| fortran | Add support for fortran | 31 |
| freetds | Add support for the TDS protocol to connect to MSSQL/Sybase databases | 2 |
| ftp | Add FTP (File Transfer Protocol) support | 4 |
| gd | Add support for media-libs/gd (to generate graphics on the fly) | 14 |
| gdbm | Add support for sys-libs/gdbm (GNU database libraries) | 24 |
| geoip | Add geoip support for country and city lookup based on IPs | 23 |
| geolocation | Enable physical position determination | 9 |
| ggi | Add support for media-libs/libggi (non-X video api/drivers) | 2 |
| gif | Add GIF image support | 38 |
| gimp | Build a plugin for the GIMP | 5 |
| git | Enable git (version control system) support | 9 |
| gles2 | Enable GLES 2.0 (OpenGL for Embedded Systems) support (independently of full OpenGL, see also: gles2-only) | 8 |
| gles2-only | Use GLES 2.0 (OpenGL for Embedded Systems) or later instead of full OpenGL (see also: gles2) | 26 |
| glut | Build an OpenGL plugin using the GLUT library | 5 |
| gmp | Add support for dev-libs/gmp (GNU MP library) | 18 |
| gnome | Add GNOME support | 24 |
| gnome-keyring | Enable support for storing passwords via gnome-keyring | 3 |
| gnuplot | Enable support for gnuplot (data and function plotting) | 8 |
| gnutls | Prefer net-libs/gnutls as SSL/TLS provider (ineffective with USE=-ssl) | 74 |
| gphoto2 | Add digital camera support | 6 |
| gpm | Add support for sys-libs/gpm (Console-based mouse driver) | 23 |
| gps | Add support for Global Positioning System | 5 |
| graphicsmagick | Build and link against GraphicsMagick instead of ImageMagick (requires USE=imagemagick if optional) | 12 |
| graphviz | Add support for the Graphviz library | 11 |
| gsl | Use the GNU scientific library for calculations | 14 |
| gsm | Add support for the gsm lossy speech compression codec | 2 |
| gstreamer | Add support for media-libs/gstreamer (Streaming media) | 32 |
| gtk | Add support for x11-libs/gtk+ (The GIMP Toolkit) | 130 |
| gtk-doc | Build and install gtk-doc based developer documentation for dev-util/devhelp, IDE and offline use | 127 |
| gui | Enable support for a graphical user interface | 93 |
| guile | Add support for the guile Scheme interpreter | 10 |
| gzip | Compress files with Lempel-Ziv coding (LZ77) | 3 |
| handbook | Enable handbooks generation for packages by KDE | 0 |
| hardened | Activate default security enhancements for toolchain (gcc, glibc, binutils) | 34 |
| hddtemp | Enable monitoring of hdd temperature (app-admin/hddtemp) | 5 |
| hdf5 | Add support for the Hierarchical Data Format v5 | 25 |
| headers-only | Install only C headers instead of whole package. Mainly used by sys-devel/crossdev for toolchain bootstrap. | 5 |
| heif | Enable support for ISO/IEC 23008-12:2017 HEIF/HEIC image format | 18 |
| hscolour | Include coloured haskell sources to generated documentation (dev-haskell/hscolour) | 0 |
| http2 | Enable support for the HTTP/2 protocol | 4 |
| ibm | Add support for IBM ppc64 specific systems | 4 |
| iconv | Enable support for the iconv character set conversion library | 20 |
| icu | Enable ICU (Internationalization Components for Unicode) support, using dev-libs/icu | 26 |
| idn | Enable support for Internationalized Domain Names | 31 |
| ieee1394 | Enable FireWire/iLink IEEE1394 support (dv, camera, ...) | 6 |
| imagemagick | Enable optional support for the ImageMagick or GraphicsMagick image converter | 22 |
| imap | Add support for IMAP (Internet Mail Application Protocol) | 2 |
| imlib | Add support for imlib, an image loading and rendering library | 7 |
| infiniband | Enable Infiniband RDMA transport support | 3 |
| initramfs | Include kernel modules in the initramfs, and re-install the kernel (only effective for distribution kernels) | 0 |
| inotify | Enable inotify filesystem monitoring support | 2 |
| introspection | Add support for GObject based introspection | 23 |
| io-uring | Enable the use of io_uring for efficient asynchronous IO and system requests | 9 |
| iodbc | Add support for iODBC library | 9 |
| ios | Enable support for Apple's iDevice with iOS operating system (iPad, iPhone, iPod, etc) | 6 |
| ipod | Enable support for iPod device access | 4 |
| ipv6 | Add support for IP version 6 | 89 |
| jack | Add support for the JACK Audio Connection Kit | 88 |
| java | Add support for Java | 51 |
| javascript | Enable javascript support | 5 |
| jbig | Enable jbig-kit support for tiff, Hylafax, ImageMagick, etc | 6 |
| jemalloc | Use dev-libs/jemalloc for memory management | 20 |
| jit | Enable just-in-time compilation for improved performance. May prevent use of some PaX memory protection features in Gentoo Hardened. | 6 |
| joystick | Add support for joysticks in all packages | 4 |
| jpeg | Add JPEG image support | 99 |
| jpeg2k | Support for JPEG 2000, a wavelet-based image compression format | 19 |
| jpegxl | Add JPEG XL image support | 20 |
| kde | Add support for software made by KDE, a free software community | 19 |
| kerberos | Add kerberos support | 70 |
| keyring | Enable support for freedesktop.org Secret Service API password store | 28 |
| ladspa | Enable the ability to support ladspa plugins | 10 |
| lame | Add support for MP3 encoding using LAME | 11 |
| lapack | Add support for the virtual/lapack numerical library | 14 |
| lash | Add LASH Audio Session Handler support | 10 |
| latex | Add support for LaTeX (typesetting package) | 13 |
| lcms | Add lcms support (color management engine) | 24 |
| ldap | Add LDAP support (Lightweight Directory Access Protocol) | 79 |
| lerc | Add LERC suppport (Limited Error Raster Compression) | 2 |
| libass | SRT/SSA/ASS (SubRip / SubStation Alpha) subtitle support | 3 |
| libcaca | Add support for colored ASCII-art graphics | 7 |
| libedit | Use the libedit library (replacement for readline) | 21 |
| libffi | Enable support for Foreign Function Interface library | 1 |
| libnotify | Enable desktop notification support | 40 |
| libsamplerate | Build with support for converting sample rates using libsamplerate | 20 |
| libwww | Add libwww support (General purpose WEB API) | 2 |
| lirc | Add support for lirc (Linux's Infra-Red Remote Control) | 14 |
| livecd | !!internal use only!! DO NOT SET THIS FLAG YOURSELF!, used during livecd building | 7 |
| llvm-libunwind | Use llvm-runtimes/libunwind instead of sys-libs/libunwind | 16 |
| lm-sensors | Add linux lm-sensors (hardware sensors) support | 9 |
| lto | Enable Link-Time Optimization (LTO) to optimize the build | 8 |
| lua | Enable Lua scripting support | 52 |
| lz4 | Enable support for lz4 compression (as implemented in app-arch/lz4) | 27 |
| lzip | Enable support for lzip compression | 6 |
| lzma | Support for LZMA compression algorithm | 42 |
| lzo | Enable support for lzo compression | 22 |
| m17n-lib | Enable m17n-lib support | 4 |
| mad | Add support for mad (high-quality mp3 decoder library and cli frontend) | 20 |
| magic | Add support for file type detection via magic bytes (usually via libmagic from sys-apps/file) | 5 |
| maildir | Add support for maildir (~/.maildir) style mail spools | 3 |
| man | Build and install man pages | 35 |
| matroska | Add support for the matroska container format (extensions .mkv, .mka and .mks) | 1 |
| mbox | Add support for mbox (/var/spool/mail) style mail spools | 6 |
| memcached | Add support for memcached | 7 |
| mhash | Add support for the mhash library | 3 |
| mikmod | Add libmikmod support to allow playing of SoundTracker-style music files | 8 |
| milter | Add sendmail mail filter (milter) support | 2 |
| minimal | Install a very minimal build (disables, for example, plugins, fonts, most drivers, non-critical features) | 167 |
| mmap | Add mmap (memory map) support | 3 |
| mms | Support for Microsoft Media Server (MMS) streams | 6 |
| mng | Add support for libmng (MNG images) | 7 |
| modplug | Add libmodplug support for playing SoundTracker-style music files | 17 |
| modules | Build the kernel modules | 3 |
| modules-compress | Install compressed kernel modules (if kernel config enables module compression) | 0 |
| modules-sign | Cryptographically sign installed kernel modules (requires CONFIG_MODULE_SIG=y in the kernel) | 0 |
| mono | Build Mono bindings to support dotnet type stuff | 5 |
| motif | Add support for the Motif toolkit | 12 |
| mp3 | Add support for reading mp3 files | 39 |
| mp4 | Support for MP4 container format | 8 |
| mpeg | Add libmpeg3 support to various packages | 3 |
| mpi | Add MPI (Message Passing Interface) layer to the apps that support it | 61 |
| mplayer | Enable mplayer support for playback or encoding | 3 |
| mssql | Add support for Microsoft SQL Server database | 5 |
| mtp | Enable support for Media Transfer Protocol | 9 |
| multilib | On 64bit systems, if you want to be able to compile 32bit and 64bit binaries | 5 |
| musepack | Enable support for the musepack audio codec | 15 |
| musicbrainz | Lookup audio metadata using MusicBrainz community service (musicbrainz.org) | 3 |
| mysql | Add mySQL Database support | 125 |
| mysqli | Add support for the improved mySQL libraries | 2 |
| nas | Add support for network audio sound | 13 |
| native-extensions | Build native (e.g. C, Rust) extensions in addition to pure (e.g. Python) code (usually speedups) | 0 |
| ncurses | Add ncurses support (console display library) | 72 |
| neXt | Enable neXt toolkit | 2 |
| netcdf | Enable NetCDF data format support | 9 |
| networkmanager | Enable net-misc/networkmanager support | 19 |
| nis | Support for NIS/YP services | 6 |
| nls | Add Native Language Support (using gettext - GNU locale utilities) | 450 |
| nntp | Add support for newsgroups (Network News Transfer Protocol) | 3 |
| nocd | Install all files required to run the application without a CD mounted | 1 |
| nsplugin | Build plugin for browsers supporting the Netscape plugin architecture (that is almost any modern browser) | 1 |
| nvenc | Add support for NVIDIA Encoder/Decoder (NVENC/NVDEC) API for hardware accelerated encoding and decoding on NVIDIA cards (requires x11-drivers/nvidia-drivers) | 4 |
| ocaml | Add support/bindings for the Ocaml language | 5 |
| ocamlopt | Enable ocamlopt support (ocaml native code compiler) -- Produces faster programs (Warning: you have to disable/enable it at a global scale) | 7 |
| oci8 | Add Oracle 8 Database Support | 3 |
| oci8-instant-client | Use dev-db/oracle-instantclient-basic as Oracle provider instead of requiring a full Oracle server install | 1 |
| odbc | Add ODBC Support (Open DataBase Connectivity) | 34 |
| offensive | Enable potentially offensive items in packages | 9 |
| ofx | Enable support for importing (and exporting) OFX (Open Financial eXchange) data files | 4 |
| ogg | Add support for the Ogg container format (commonly used by Vorbis, Theora and flac) | 19 |
| openal | Add support for the Open Audio Library | 19 |
| opencl | Enable OpenCL support (computation on GPU) | 26 |
| openexr | Support for the OpenEXR graphics file format | 17 |
| opengl | Add support for OpenGL (3D graphics) | 103 |
| openmp | Build support for the OpenMP (support parallel computing), requires >=sys-devel/gcc-4.2 built with USE="openmp" | 107 |
| opentype-compat | Convert BDF and PCF bitmap fonts to OTB wrapper format | 0 |
| opus | Enable Opus audio codec support | 30 |
| oracle | Enable Oracle Database support | 7 |
| orc | Use dev-lang/orc for just-in-time optimization of array operations | 2 |
| osc | Enable support for Open Sound Control | 9 |
| oss | Add support for OSS (Open Sound System) | 65 |
| otf | Install OpenType font versions | 1 |
| pam | Add support for PAM (Pluggable Authentication Modules) - DANGEROUS to arbitrarily flip | 101 |
| pch | Enable precompiled header support for faster compilation at the expense of disk space and memory | 11 |
| pcmcia | Add support for PCMCIA slots/devices found on laptop computers | 2 |
| pcre | Add support for Perl Compatible Regular Expressions | 42 |
| pda | Add support for portable devices | 1 |
| pdf | Add general support for PDF (Portable Document Format), this replaces the pdflib and cpdflib flags | 54 |
| perl | Add optional support/bindings for the Perl language | 69 |
| php | Include support for the PHP language | 5 |
| pie | Build programs as Position Independent Executables (a security hardening technique) | 3 |
| plasma | Build optional KDE plasma addons | 5 |
| plotutils | Add support for plotutils (library for 2-D vector graphics) | 3 |
| png | Add support for libpng (PNG images) | 110 |
| policykit | Enable PolicyKit (polkit) authentication support | 26 |
| portaudio | Add support for the crossplatform portaudio audio API | 32 |
| posix | Add support for POSIX-compatible functions | 1 |
| postgres | Add support for the postgresql database | 123 |
| postscript | Enable support for the PostScript language (often with ghostscript-gpl or libspectre) | 18 |
| ppds | Add support for automatically generated ppd (printing driver) files | 1 |
| prefix | Defines if a Gentoo Prefix offset installation is used | 4 |
| profile | Add support for software performance analysis (will likely vary from ebuild to ebuild) | 17 |
| pulseaudio | Add sound server support via media-libs/libpulse (may be PulseAudio or PipeWire) | 121 |
| python | Add optional support/bindings for the Python language | 181 |
| qdbm | Add support for the qdbm (Quick Database Manager) library | 3 |
| qmail-spp | Add support for qmail SMTP plugins | 3 |
| qt5 | Add support for the Qt 5 application and UI framework | 51 |
| qt6 | Add support for the Qt 6 application and UI framework | 50 |
| quicktime | Add support for OpenQuickTime | 2 |
| radius | Add support for RADIUS authentication | 10 |
| raw | Add support for raw image formats | 18 |
| rdp | Enables RDP/Remote Desktop support | 5 |
| readline | Enable support for libreadline, a GNU line-editing library that almost everyone wants | 97 |
| recode | Enable support for the GNU recode library | 1 |
| rss | Enable support for RSS feeds | 7 |
| ruby | Add support/bindings for the Ruby language | 28 |
| samba | Add support for SAMBA (Windows File and Printer sharing) | 25 |
| sasl | Add support for the Simple Authentication and Security Layer | 51 |
| savedconfig | Use this to restore your config from /etc/portage/savedconfig ${CATEGORY}/${PN}. Make sure your USE flags allow for appropriate dependencies | 12 |
| scanner | Add support for scanner hardware (e.g. build the sane frontend in kdegraphics) | 9 |
| screencast | Enable support for remote desktop and screen cast using PipeWire | 10 |
| sctp | Support for Stream Control Transmission Protocol | 9 |
| sdl | Add support for Simple Direct Layer (media library) | 65 |
| seccomp | Enable seccomp (secure computing mode) to perform system call filtering at runtime to increase security of programs | 21 |
| secureboot | Automatically sign efi executables using user specified key | 0 |
| selinux | !!internal use only!! Security Enhanced Linux support, this must be set by the selinux profile or breakage will occur | 315 |
| semantic-desktop | Cross-KDE support for semantic search and information retrieval | 5 |
| session | Add persistent session support | 5 |
| sid | Enable SID (Commodore 64 audio) file support | 7 |
| skey | Enable S/Key (Single use password) authentication support | 2 |
| slang | Add support for the slang text display library (it's like ncurses, but different) | 9 |
| smartcard | Enable smartcard support | 14 |
| smp | Enable support for multiprocessors or multicore systems | 2 |
| snappy | Enable support for Snappy compression (as implemented in app-arch/snappy) | 5 |
| sndfile | Add support for libsndfile | 21 |
| snmp | Add support for the Simple Network Management Protocol if available | 30 |
| soap | Add support for SOAP (Simple Object Access Protocol) | 1 |
| sockets | Add support for tcp/ip sockets | 3 |
| socks5 | Add support for the socks5 proxy | 9 |
| sound | Enable sound support | 17 |
| source | Zip the sources and install them | 15 |
| sox | Add support for Sound eXchange (SoX) | 7 |
| speech | Enable text-to-speech support | 23 |
| speex | Add support for the speex audio codec (used for speech) | 16 |
| spell | Add dictionary support | 28 |
| split-usr | Enable behavior to support maintaining /bin, /lib*, /sbin and /usr/sbin separately from /usr/bin and /usr/lib* | 20 |
| sqlite | Add support for sqlite - embedded sql database | 81 |
| ssl | Add support for SSL/TLS connections (Secure Socket Layer / Transport Layer Security) | 218 |
| startup-notification | Enable application startup event feedback mechanism | 11 |
| static | !!do not set this during bootstrap!! Causes binaries to be statically linked instead of dynamically | 112 |
| static-libs | Build static versions of dynamic libraries as well | 628 |
| strip | Allow symbol stripping to be performed by the ebuild for special files | 0 |
| subversion | Enable subversion (version control system) support | 9 |
| suid | Enable setuid root program(s) | 22 |
| svg | Add support for SVG (Scalable Vector Graphics) | 42 |
| svga | Add support for SVGAlib (graphics library) | 8 |
| symlink | Force kernel ebuilds to automatically update the /usr/src/linux symlink | 7 |
| syslog | Enable support for syslog | 13 |
| systemd | Enable use of systemd-specific libraries and features like socket activation or session tracking | 242 |
| szip | Use the szip compression library | 6 |
| taglib | Enable tagging support with taglib | 16 |
| tcl | Add support the Tcl language | 29 |
| tcmalloc | Use the dev-util/google-perftools libraries to replace the malloc() implementation with a possibly faster one | 15 |
| tcpd | Add support for TCP wrappers | 45 |
| telemetry | Send anonymized usage information to upstream so they can better understand our users | 15 |
| test | Enable dependencies and/or preparations necessary to run tests (usually controlled by FEATURES=test but can be toggled independently) | 2567 |
| test-install | Install testsuite for manual execution by the user | 2 |
| test-rust | Enable important test dependencies that require Rust toolchain | 18 |
| theora | Add support for the Theora Video Compression Codec | 11 |
| threads | Add threads support for various packages. Usually pthreads | 88 |
| tidy | Add support for HTML Tidy | 1 |
| tiff | Add support for the TIFF image format | 61 |
| time64 | Use 64-bit time_t type instead of the regular 32-bit type. This flag is forced on time64 profiles, and masked elsewhere. It should be only used when detection of type width is not possible (e.g. for SRC_URI) | 0 |
| timidity | Build with Timidity++ (MIDI sequencer) support | 8 |
| tk | Add support for Tk GUI toolkit | 45 |
| truetype | Add support for FreeType and/or FreeType2 fonts | 49 |
| ttf | Install TrueType font versions | 4 |
| udev | Enable virtual/udev integration (device discovery, power and storage device support, etc) | 44 |
| udisks | Enable storage management support (automounting, volume monitoring, etc) | 8 |
| uefi | Enable support for the Unified Extensible Firmware Interface | 8 |
| unicode | Add support for Unicode | 49 |
| unwind | Add support for call stack unwinding and function name resolution | 22 |
| upnp | Enable UPnP port mapping support | 18 |
| upnp-av | Enable UPnP audio/video streaming support | 3 |
| upower | Enable power management support | 9 |
| usb | Add USB support to applications that have optional USB support (e.g. cups) | 36 |
| v4l | Enable support for video4linux (using linux-headers or userspace libv4l libraries) | 22 |
| vaapi | Enable Video Acceleration API for hardware decoding | 15 |
| vala | Enable bindings for dev-lang/vala | 53 |
| valgrind | Enable annotations for accuracy. May slow down runtime slightly. Safe to use even if not currently using dev-debug/valgrind | 48 |
| vanilla | Do not add extra patches which change default behaviour; DO NOT USE THIS ON A GLOBAL SCALE as the severity of the meaning changes drastically | 23 |
| vcd | Video CD support | 4 |
| vdpau | Enable the Video Decode and Presentation API for Unix acceleration interface | 11 |
| verify-sig | Verify upstream signatures on distfiles | 92 |
| vhosts | Add support for installing web-based applications into a virtual-hosting environment | 2 |
| videos | Install optional video files (used in some games) | 5 |
| vim-syntax | Pulls in related vim syntax scripts | 22 |
| vnc | Enable VNC (remote desktop viewer) support | 12 |
| vorbis | Add support for the OggVorbis audio codec | 60 |
| vpx | Add support for VP8/VP9 codecs (usually via media-libs/libvpx) | 11 |
| vulkan | Add support for 3D graphics and computing via the Vulkan cross-platform API | 29 |
| wavpack | Add support for wavpack audio compression tools | 19 |
| wayland | Enable dev-libs/wayland backend | 135 |
| webkit | Add support for the WebKit HTML rendering/layout engine | 14 |
| webp | Add support for the WebP image format | 39 |
| wifi | Enable wireless network functions | 7 |
| wmf | Add support for the Windows Metafile vector image format | 4 |
| wxwidgets | Add support for wxWidgets/wxGTK GUI toolkit | 14 |
| x264 | Enable h264 encoding using x264 | 10 |
| xattr | Add support for extended attributes (filesystem-stored metadata) | 28 |
| xcb | Support the X C-language Binding, a replacement for Xlib | 2 |
| xcomposite | Enable support for the Xorg composite extension | 1 |
| xemacs | Add support for XEmacs | 3 |
| xface | Add xface support used to allow a small image of xface format to be included in an email via the header 'X-Face' | 4 |
| xft | Build with support for XFT font renderer (x11-libs/libXft) | 14 |
| xine | Add support for the XINE movie libraries | 1 |
| xinerama | Add support for querying multi-monitor screen geometry through the Xinerama API | 43 |
| xinetd | Add support for the xinetd super-server | 11 |
| xml | Add support for XML files | 42 |
| xmlrpc | Support for xml-rpc library | 3 |
| xmp | Enable support for Extensible Metadata Platform (Adobe XMP) | 8 |
| xmpp | Enable support for Extensible Messaging and Presence Protocol (XMPP) formerly known as Jabber | 3 |
| xosd | Sends display using the X On Screen Display library | 2 |
| xpm | Add support for XPM graphics format | 15 |
| xscreensaver | Add support for XScreenSaver extension | 4 |
| xv | Add in optional support for the Xvideo extension (an X API for video playback) | 10 |
| xvid | Add support for xvid.org's open-source mpeg-4 codec | 2 |
| zeroconf | Support for DNS Service Discovery (DNS-SD) | 39 |
| zip | Enable support for ZIP archives | 14 |
| zlib | Add support for zlib compression | 119 |
| zsh-completion | Enable zsh completion support | 2 |
| zstd | Enable support for ZSTD compression | 54 |