mapm is a problem-management software that allows you to quickly iterate through drafts of exams. By modularizing your problems into their own files, you can easily mix and match problems and compile exams and solution manuals.
By using built-in TeX macros and a sane implementation of the incredibly human-readable YAML configuration language, you can spend less time learning how to organize your exam creation process and more time on the exam itself.
Read the library documentation for mapm at docs.rs/mapm and the usage instructions at mapm.mathadvance.org/.
mapm is meant for you if you are an exam-creator or contest writer whose template has a fixed number of problems. Thus, contests like the AMCs can be typeset with mapm, while exams like the SAT or school tests with a variable number of questions do not have the same level of support (though you may get some use out of mapm, especially if you write your own binary wrapper around the library).
If you have Rust on your system, run cargo install mapm to get the latest and greatest from cargo. If you do not, binaries will be released for every major version.
You can also run git clone and cargo build to manually install from source.
I am of the belief that you should modify the source code to fit any edge-case needs, rather than the code providing a bunch of complex hooks that would be more difficult to use than simpler source code. For example, the behavior of the interface that transforms the list of authors in a contest to the \contestauthors TeX macro can easily be modified by someone, even with zero prior Rust experience.
Therefore, users are encouraged to keep their own builds of the mapm library if inclined to, and to propose any particularly well-designed solutions to upstream.