Moss is a thin layer grown on top of GNU make that streamlines the creation of high-performance multi-tool-chain build systems for large code bases.

Rather than trying to create an entirely new build tool or introduce a code generation step before running an existing build tool, Moss leverages powerful building blocks integrated into GNU make.

Moss focuses primarily on the following goals:

• Efficiently compiling C and C++ source files into object files
• Automatically generating and managing robust dependency information
• Easily creating a variety of outputs (libraries, executables, image dumps, etc.) as required by most non-trivial software development
• Cleanly managing multiple build variants with differing toolchain settings

Moss was built with the understanding that build speed matters, particularly when working in test-driven development flows that require frequent compile-link-test cycles. For typical large trees (e.g. 10,000 source files), build systems implemented with Moss execute a full dependency check (make has nothing to do) and return to the prompt in under 1 second.

Portability is maximized by:

• Standardizing on GNU make 4.2+ as THE BUILD TOOL rather than attempting to work with multiple incompatible build tools
• Providing out-of-the-box support for mainstream gcc and clang compilers
• Separating the description of the source tree from the implementation of the build system
• Separating tool-independent descriptions from tool-specific options

Moss is targeted at C and C++ code bases, but it may apply well to other native languages with similar compilation flows.