arduino-mk : Makefile for Arduino sketches. ( https://github.com/sudar/Arduino-Makefile )
icestorm : IceStorm - tools for analyzing and creating bitstreams for Lattice iCE40 FPGAs ( http://www.clifford.at/icestorm/ )
nextpnr : portable FPGA place and route tool ( https://github.com/YosysHQ/nextpnr )
teensyduino-bin : USB-based electronics prototyping platform compatible with Arduino ( https://www.pjrc.com/teensy/ )
yosys : Yosys - Yosys Open SYnthesis Suite ( http://www.clifford.at/icestorm/ )
Add an ebuild in portage :
The ebuild is now in the portage tree.
You can also use layman : emerge layman then layman -a concaveoverlay
For Paludis use this rsync : rsync://gentoo.zugaina.org/concaveoverlay-portage
If you have a problem : ycarus(-at-)zugaina.org