I use this repository for my personal Iosevka configuration and documentation.
Building Iosevka from Source - GitHub Iosevka Customizer
Clone source repo
git clone --depth 1 https://github.com/be5invis/Iosevka.git
Install needed software (on Mac)
brew install node ttfautohint
Go to the directory where the Iosevka source code directory and install node dependencies.
cd Iosevka
npm install
Copy or link the private-build-plans.toml file from this repository to the git repo root directory. When you have done that you can build the Iosevka font. Please note that in the example below I use 6 build processes. These consume about 1GB or RAM and 1 CPU core each.
npm run build -- ttf::IosevkaCustom --jCmd=6
The font files are now located in the dist directory