mx is a command line based tool for managing the development of (primarily) Java code. It includes a mechanism for specifying the dependencies as well as making it simple to build, test, run, update, etc the code and built artifacts. mx contains support for developing code spread across multiple source repositories. mx is written in Python (version 2.7) and is extensible.
The organizing principle of mx is a suite. A suite is a directory containing one or more projects and also under the control of a version control system. A suite may import one or more dependent suites. One suite is designated as the primary suite. This is normally the suite in whose directory mx is executed. The set of suites that are reachable from the primary suite by transitive closure of the imports relation form the set that mx operates on. The set of suites implicitly defines the set of projects. The action of building a suite is to compile the code in the projects and generate one or more distributions which are 'jar' files containing the compiled classes and related metadata.
mx can be run directly (i.e., python2.7 mx/mx.py ...), but is more commonly invoked via the mx/mx bash script (which includes a Python version check). Adding the mx/ directory to your PATH simplifies executing mx. The mx/mx.cmd script should be used on Windows.
The general form of the mx command line is:
mx [global options] [command] [command-specific options]
If no options or command is specified, mx prints information on the available options and commands, which will include any suite-specfic options and commands. Help for a specific command is obtained via mx help <command>. Global options are expected to have wide applicability to many commands and as such precede the command to be executed.
For an example of mx usage, you can read the Instructions for the Graal project.