Command-line tools written in Gauche, which I actually use (e.g. JSON and link validation in Talk Dim Sum).

Install Gauche (it's also possible to build these as standalone executables), add this directory to your PATH, and you can invoke, for example

files.scm -t swift

which will count the number of .swift files in the current directory and below.

• files.scm - counts files
• indent.scm - indents lisp files
• jsonvalid.scm - checks valid json in each file
• links.scm - search/check links
• lines.scm - counts lines in each file
• search.scm - search for text (regexp)
• size.scm - total of the file sizes
• urlfix.scm - repairs links
• libs - some reusable functions

Use the -h option to print help for each command.