Is a 100ms startup time really a big deal for something that is either going to be manually triggered or cronjobbed and expected to take on the order of minutes?

Those sorts of startup times discourage writing command-line tools (e.g. composable text processing things one might join with pipes).

Ruby scripting has occupied the sysadmin space for over a decade yet on my 2013 Macbook Pro the latest Ruby 2.6.5 takes around 250ms to start. That's a mere 1/4 of a second. Sure, Python, Perl and PHP have shorter startup times but surely this is a non-problem?

No, things like sort, grep, uniq, cut, wc, cat, awk, sed, tr, etc etc. You wouldn't want them to take 1/4 second to start up.

Crystal's startup time is not great though. 700ms vs 100ms for ruby.

Compared with

   time crystal eval <<<"puts 1"
   time ruby <<<"puts 1"

You know that you are timing the compiler and not the compiled program here?

Rather try "echo 'puts 1' > puts.cr && crystal build puts.cr && time ./puts"

BTW, you can dramatically decrease the cold startup times of ruby if you call it with the options '--disable-gems --disable-rubyopt' if that's an option to you. For many scripts it certainly is.

But even on a 8 years old machine with spinning rust, after the ruby stuff is cached in the OS filesystem cache, my startup time are smaller than 10ms.