The Eclipse Handly project provides basic building blocks for handle-based models, with an emphasis on language-specific source code models of the underlying Eclipse workspace. It allows creating highly scalable, robust, and thoroughly optimized models similar in design principles to the tried-and-tested Java model of Eclipse Java development tools while reducing programming effort, fostering software reuse, and enabling interoperability.
Handly is designed for flexibility and can be used to create source code models for practically any language, whether general-purpose or domain-specific; it is compatible with any parsing technology. Since version 0.5, the model implementor has complete control over the model's base-level API, including the ability to implement a preexisting handle-based model API. At the same time, the provided uniform meta-level API establishes a common language and makes it possible for IDE components to work in a generic way with any Handly-based model.