Global USE flags

Flag Description Packages
doc 3
lto Enable Link Time Optimization, runs smoother with more particles 2

Local USE flags

app-crypt

gtkhash

Flag Description
caja Build the checksums plugin for use inside Caja from MATE
mbedtls Support calculating checksums with net-libs/mbedtls
nemo Build the checksums plugin for use inside Nemo from Cinnamon
nettle Support calculating checksums with dev-libs/nettle
openssl Support calculating checksums with libcrypto from dev-libs/openssl
thunar Build the checksums plugin for use inside Thunar from XFCE

dev-cpp

sockpp

Flag Description
static-libs
test
utils Install example utilities to check TCP, UDP, etc. latency

games-simulation

powdertoy

Flag Description
curl Enable online functionality using libcurl
lua

simutrans

Flag Description
fontconfig
midi Support for background MIDI music via <pkg>media-sound/fluidsynth</pkg>
tools Build makeobj to compile new paksets, and nettool to interact with dedicated servers
upnp
zstd

games-util

xwiimote

Flag Description
X Install xorg.conf.d snippet to avoid weird mouse behavior from raw Wiimote inputs
debug

net-p2p

syncthing-gtk

Flag Description
appindicator
libnotify