1. A method of facilitating cloud-based source code editing for developing an application, comprising: providing a source code editor for generating source code of an application, where the source code editor dynamically supports third party libraries, including new and updated third party libraries not previously supported by the source code editor; performing an editing function by a user using the source code editor; invoking an auto-completion editing feature of the source code editor to complete the source code, wherein the auto-completion editing feature provides auto-completion proposals; invoking a metadata packager for generating a metadata package, wherein the metadata package comprises metadata of third party libraries, including new and updated third party libraries; providing the metadata package to the source code editor; and providing auto-completion proposals to the user, wherein the auto-completion proposals is based on the metadata in the metadata package.