This repository contained an open source FPGA toolchain for Lattice FPGAs, but is obsolete now.

The toolchain can simply be installed on a recent debian system by installing these packages:

yosys yosys-abc nextpnr-ice40 nextpnr-ice40-chipdb nextpnr-ecp5 nextpnr-ecp5-chipdb fpga-icestorm fpga-icestorm-chipdb iverilog gtkwave