A parser and interpreter for FEEL that is written in Scala (see What is FEEL?).

The FEEL engine started as a slack time project, grown to a community-driven project, and is now officially maintained by Camunda. 🚀

It is integrated in the following projects:

• Camunda Platform as part of the DMN engine
• Zeebe as the expression language

Features: ✨

• Full support for unary-tests and expressions
• Including built-in functions
• Extensible by custom functions and object mappers

Please have a look at the documentation. It describes how to write FEEL expressions (e.g. data types, language constructs, builtin-functions, etc.). Or, check out examples and learning resources here.

Want to try it out? Use the Playground to evaluate FEEL expressions.

Please have a look at the developer documentation. It describes how to integrate the engine into your application, and how to extend/customize it.

Contributions are welcome 🎉 Please have a look at the Contribution Guide.

The following resources can help to understand some general concepts behind the implementation:

• Build your own Programming Language with Scala
• Easy Parsing with Parser Combinators
• FastParse - Documentation of the Parser Library

Apache License, Version 2.0