Unable to create elm-reduce binary

I followed the instructions in the readme.

• Add stack
• git clone https://gitlab.com/matheus23/elm-reduce
• cd elm-reduce
• stack install

I got stuck at the last part (stack install). The following is the output on my terminal.

➜  elm-reduce git:(master) stack install
Stack looks for packages in the directories configured in
the 'packages' and 'extra-deps' fields defined in your stack.yaml
The current entry points to /Users/<..redacted..>/elm-reduce/elm-format/,
but no .cabal or package.yaml file could be found there.

➜  elm-reduce git:(master) ls
CHANGELOG.md     README.md        elm-reduce.cabal stack.yaml       test-data
LICENSE          Setup.hs         exe              stack.yaml.lock  thesis.pdf
Passes.md        elm-format       src              test

Is there anything that I'm doing wrong here?