BitBake is a task scheduler that parses Python and shell script mixed code. The code parsed generates and runs tasks, which are basically a set of steps ordered per the code's dependencies.
It evaluates all available configuration files and recipe data (known as metadata), managing dynamic variable expansion, dependencies, and code generation. It keeps track of all tasks being processed in order to ensure completion, maximizing the use of processing resources to reduce build time and being predictable. The development of BitBake is centralized in the bitbake-devel@lists.openembedded.org mailing list, and its code can be found in the bitbake subdirectory of Poky.