Legal

Licence

Speedy Make is distributed under the GNU GPL 2.0 licence.
You can use and share freely the program provided the copyright notice is included and the headers unchanged.
You can extend the program and distribute the extended version provided the name of the original author is kept, and its copyright notice unchanged. According to the licence, the modified source code must be provided also.
The source is the Scriptol source, not the C++ backend that is an intermediate code.

Including the executable

You have special authorization to include the binary executable along with your program without the need to include the source providing it is unchanged. If the original source here provided is changed, you must provide it either along with the executable or separatly.

Speedy Make's makefiles

The format of the makefile is under the Creative Common licence.
You can provide files in this format without restriction for use with Speedy Make.
If you use the format with another tool, rather than with Speedy Make, you have to specify the name of the original author in the documentation about the format.