Here's how to create a nitter user, clone the repo, and build the project along with the scss.
# useradd -m nitter
# su nitter
$ git clone https://github.com/zedeus/nitter
$ cd nitter
$ nimble build -d:release
$ nimble scss
$ mkdir ./tmp
Hard to make sense of all that :/What's 'Nimble' and 'scss'?