When:
```bash
$ bundle exec cucumber
bundler: command not found: cucumber
Install missing gem executables with `bundle install`
```
Do:
```bash
$ rm .bundle/config # remove a broken bundler configuration
$ gem update --system # might help if rubygems is outdated / broken
$ gem update bundler # might help if bundler is outdated / broken
$ bundle install # dependency hell
```
Or, start using, e.g., golang, crystal, etc.