You can build apps and services on webOS Open Source Edition (OSE) using the following APIs and libraries:
LS2 API is an interface to access system services via Luna Bus and use their functionalities. LS2 API forms the basis of webOS app and service development. See the LS2 API index.
webos-service library provides the API to the system bus wrapped in familiar Node.js idioms. See webos-service Library API reference.
luna-service2 library provides a C/C++ API used by native apps and services in order to call LS2 API methods. See luna-service2 Library API reference.
pmloglib library provides the API for debugging, which allows you to trace and log the runtime status of apps or services. See pmloglib Library API reference.