No need for a Makefile

[totikom]

Literally every LaTeX distribution comes with a small script latexmk which is already capable of doing everything in your Makefile.

Build (makes all the necessary runs and figures what is needed by itself):
latexmk --xetex --pdf or latexmk --lualatex --pdf

Clean temporary files:
latexmk -c

Clean both temporary and output files:
latexmk -C

[anishathalye]

Sure, migrated to latexmk in 6750404. Thanks for the suggestion.

[totikom]

Just in case someone doesn't have latexmk in their distribution, add it to Dependencies section.

[anishathalye]

Added in 5102701.