Presets and custom oscillators and effects for the prologue synthesizer.
In order to build these projects you have to get the prologue SDK and copy any of the project directories to some new directory in logue-sdk/platform/prologue/; for example copy src/pluck/ to logue-sdk/platform/prologue/len/pluck/ and then you can build with make.
If you don't want to write code and compile, just download the prebuilt binaries from the builds/ directory.