@deanishe I have an app, written in kotlin, that is packaged as a 22Mb fat jar file. Libraries are non-trivial -- sqlite, micronaut, picocli, kotlin statistics. There's really no need for micronaut in this app, but I'm experimenting with it, so there it is. I have not yet done any testing with Alfred
The app does a read-only query on the sqlite database of the application "Bear" to get the text of all the notes modified in the last month, then does some regex matching on note text to find certain things and compile a little report that is formatted as a markdown outline. My current Bear database isn't very large, but grows every day. This application runs (timed by the unix 'time' command) from the command line in about 180ms.
Startup time is, indeed, java's weakness when compared to something like a shell script. But if you don't use reflective DI frameworks like Spring you can keep things reasonable.