I have a module I'd like to release to CPAN, and I like using dzil to do the packaging and releasing. However, the module relies on an external application, and while I know where it is installed on my machine, I'd like to ask users to input where it is installed on their machine. Having read Prompt user during unit test in Perl I see ExtUtils::MakeMaker::prompt does just what I want to do.
How would I incorporate that (or something similar) when using dzil?
The standard MakeMaker dzil plugin has no support for anything but a basic Makefile.PL. (Well, it can use File::ShareDir::Install, but that's its limit.) If you need more complex install-time behavior, you'll need to use something else.
I recommend my MakeMaker::Custom plugin. You write your own Makefile.PL, which can do anything that ExtUtils::MakeMaker is capable of, including prompt for information. You can still have dzil add things like your prerequisites at dzil build time, so you can still use AutoPrereqs. (Actually, I recommend ModuleBuild::Custom instead, but if you want to stick with MakeMaker, that's ok.)
Note: You should also allow the information you're prompting for to be supplied on the command line. This will help people who are trying to package your distribution using automated build tools. But that's a MakeMaker issue, not a Dist::Zilla one.