HTTP Libraries HTTP libraries are a type of KiCad symbol library that sources data about parts for an external source such an ERP system. They do not contain any symbol or footprint definitions as standard KiCad libraries do. Instead, they reference to symbols and footprints found in other KiCad libraries. HTTP libraries are read only for now but will eventually support read/write in the future. At the moment only REST or REST-Like APIs are supported but support for other libraries could be added easily.
KiCad implements a Python plugin interface so that external Python plugins can be run from within the PCB editor. The interface is generated using the Simplified Wrapper and Interface Generator or SWIG. SWIG is instructed to translate specific C/C++ header files into other languages using interface files. These files ultimately decide what C/C++ functions, classes and other declarations are exported and can be found in pcbnew/swig/. During build-time the SWIG interface files are used to generate the corresponding .