This is a tutorial on monad transformers.
The PDF version of the tutorial is in subdirectory pdf.
You can load the code into ghci and play with it like this:
ghci Transformers.lhs
:t eval2b
On Debian 10, the following should work and create Transformers.pdf:
sudo apt install texlive
lhs2TeX Transformers.lhs > Transformers.tex
pdflatex Transformers.tex
bibtex Transformers.aux
pdflatex Transformers.tex