Global USE flags

Flag	Description	Packages
debug	Enable debug output in dmesg	5
dkms	Manage external kernel modules with sys-kernel/dkms	0
doc		3
examples		3
firmware	Install device firmware	2
module	Compile the actual WireGuard kernel module. Most certainly you want this enabled, unless you're doing something strange.	2
modules	Build netatop kernel module and install netatopd daemon.	2
python		3
udev	Controls installation of special USB udev rules.	2

Category USE flags

app-emulation

Flag	Description	Packages
dbus		2
gui		2

net-misc

Flag	Description	Packages
multi-tx-q	Enable Multiple Tx Queue ('RSS' for sending)	2
rss	Enable Receive Side Scaling (RSS)	2
use-firmware	Support automatic firmware loading	2

Local USE flags

app-emulation

virtualbox

Flag	Description
alsa
dtrace	Install dtrace Extension Pack.
headless	Build without any graphic frontend.
java
lvm	Build VBoxVolInfo that needs devicemapper from <pkg>sys-fs/lvm2</pkg>.
nls
opengl
pam
pax-kernel	Apply patch needed for pax enabled kernels.
pch
pulseaudio
sdk	Enable building of SDK.
sdl
vboxwebsrv	Build and install the VirtualBox webservice.
vde	Support for VDE networking via <pkg>net-misc/vde</pkg>.
vmmraw	Enable 32-bit support on a 64-bit kernel.
vnc

app-laptop

tp_smapi

Flag	Description
hdaps	Install a compatible HDAPS module

media-video

droidcam

Flag	Description
gtk	Build the <pkg>dev-cpp/gtkmm</pkg>:3.0 client.

net-firewall

ipt_netflow

Flag	Description
natevents	Netflow NAT translation events (NEL) support
snmp

net-misc

r8125

Flag	Description
ptp	Enable Precision Time Protocol support

r8152

Flag	Description
center-tap-short	Enable support for center tap short

r8168

Flag	Description
down-speed-100	Reduce speed to 100 Mbps in WOL-only modes
eee	Enable Energy-Efficient Ethernet by default
giga-lite	Enable support of 'Giga Lite' (500 Mbps over just two CAT5 pairs) by default
hw-acceleration	Enable use of hardware acceleration by default. HW acceleration may cause problems on Realtek NICs!
s5-keep-mac	Keep set MAC address in S5 (switched off) by default
wol	Enable Wake-On-LAN by default
wol-s5	Enable start from S5 (switched off) by Wake-On-LAN by default

net-vpn

wireguard-modules

Flag	Description
module-src	Install the module source code to /usr/src, in case you like building kernel modules yourself.

sci-libs

linux-gpib

Flag	Description
guile
pcmcia
perl
php
static
tcl

sci-pt

picoscope

Flag	Description
gnome-keyring

sys-apps

openrazer

Flag	Description
client	Build the OpenRazer daemon client
daemon	Build the OpenRazer daemon service

sys-fs

loop-aes

Flag	Description
cpu_flags_x86_aes
cpu_flags_x86_padlock
extra-ciphers	Enable extra ciphers
keyscrub	Protects the encryption key in memory but takes more cpu resources

scoutfs

Flag	Description
test

zfs-kmod

Flag	Description
custom-cflags
dist-kernel-cap	Prevents upgrading to an unsupported kernel version when combined with USE=dist-kernel
rootfs	Pull dependencies and check kernel options required for root-on-zfs

x11-drivers

nvidia-drivers

Flag	Description
X
abi_x86_32
abi_x86_64
kernel-open	Use the open source variant of the drivers (Turing/Ampere+ GPUs only, aka GTX 1650+ -- recommended with >=560.xx drivers if usable and it may be required for 50xx Blackwell+ GPUs)
persistenced	Install the persistence daemon for keeping devices state when unused (e.g. for headless)
powerd	Install the NVIDIA dynamic boost support daemon (only useful with specific laptops, ignore if unsure)
static-libs	Install the XNVCtrl static library for accessing sensors and other features
tools	Install additional tools such as nvidia-settings
wayland

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