To deploy the blog use:
./site build
If you change site.hs, then recompile and rebuild:
ghc --make site.hs
./site rebuild
If you are using Stack then it will use the .cabal and .yaml files. To build the site, do:
stack build
.stack-work/install/x86_64-linux/lts-3.18/7.10.2/bin/stack-project build
And then get the full site from _site as usual.