The getopt thing was an experiment, and I'd rather lose external dependencies than use getopt-like parsing especially since the only argument this app takes is largely for testing/development purposes only.
See: #6
https://github.com/golang/go/wiki/Modules#should-i-commit-my-gosum-file-as-well-as-my-gomod-file `go mod tidy` was also run on the go.mod file