Steps to do during a release

Make sure the version in the cabal file matches the planned release number
Adjust the stack template with that version and test whether it works
Run the test suite for good measure
Create the haddocks and fix errors/warnings
Update the CHANGELOG.md file
Commit and push everything (do not tag yet)
Create a distribution tarball and build/test with the contents
Tag if travis build is okay
Generate the haddock documentation (unless you know you don't have to)
Generate a distribution tarball
Upload tarball and documentation
Create a new commit where the version numbers are incremented