Similar to CUPS

GNU Hello

GNU Multiple Precision Arithmetic Library

GNUnet

GObject

GPAC Project on Advanced Content

HarfBuzz

Igraph

Iperf

Julia (programming language)

Kitty (terminal emulator)

LADSPA

Leafpad

Libavcodec

LibreSSL

Libvirt

Libwww

Lighttpd

Linux-libre

Linux kernel

LIRC

Lis (linear algebra library)

MDB Tools

Mesa (computer graphics)

Metacity

TinySPARQL

MicroEMACS

MicroPython