The o42a compiler and source code are available under the terms of GNU General Public License, version 3 or later.

The run-time libraries and source code are available under the terms of Mozilla Public License, version 2.0

Source Code

The source code is available for download here.

The latest sources can be obtained from project’s Mercurial repository. For that, type the following command in console:

hg clone

Or follow to the source section at Bitbucket.

Information about releases can be found here.



o42a works on GNU/Linux with x86_64 architecture. Other configurations not tested.


Customize The Build

You may be required to customize the build. For that:

  • enter the ‘build’ directory,
  • locate the files you want to customize (those with names containing .default. sub-string) and follow customization instructions inside.


Once all dependencies installed, enter the directory, where o42a located and invoke the following command:



o42a does not require a special installation procedure. To invoke o42ac just add the o42a directory to the PATH environment variable or create an alias for o42ac executable.

“Hello, World!” Execution

Enter the examples directory and type in the following command:

ant hello-world

to compile and run the program, or

ant compile

to only compile, but not execute it.

The compiled executable will be called bin/hello_world.