Earlier quoted context omitted.
50MiB to 6MiB The binaries are mostly stuff like pandoc and compiled statically so that I can run them anywhere. Nothing too special. Its not technically needed, but it makes network transfer faster and in general thats good enough. Its not really intended to reduce disk space really, just more a way to make things more manageable.
Curious — which network transfer protocol are you using that doesn’t support compression on the fly? And if its just for transfer, why not gzip instead?
UPX is usually better than other generic compression utilities. IIRC it actually modifies the executable before compressing it to provide better compression. I think on Windows it reversibly changes relative addresses to absolute addresses so you get better compression rates.