Setup the environment.
sudo apt-get install git-core libncurses5 libncurses5-dev m4 bison gawk flex libstdc++6-4.4-dev g++-4.4 g++ git zlib1g-dev
If running a 64 bit OS, you'll need the 32 bit build tools: sudo apt-get install libc6-i386 lib32z-dev
git clone git@github.com:ReliefLabs/EasyTomato.git
sudo ln -s $HOME/EasyTomato/tools/brcm /opt/brcm
echo "export PATH=$PATH:/opt/brcm/hndtools-mipsel-linux/bin:/opt/brcm/hndtools-mipsel-uclibc/bin" >> ~/.profile
source ~/.profile
Build the firmware
cd ~/EasyTomato/release/src-rt
make r2nc V1=<build> V2=<optional-suffix>
V1 and V2 specify build number and an extra suffix. Both are optional.