Cameleon is a free and open source graphical language for functional programming, released under an MIT License.

Cameleon language is a graphical data flow language following a two-scale paradigm. It allows an easy up-scale, that is, the integration of any library writing in C++ into the data flow language. Cameleon language aims to democratize macro-programming by an intuitive interaction between the human and the computer where building an application based on a data-process and a GUI is a simple task to learn and to do. Cameleon language allows conditional execution and repetition to solve complex macro-problems.

Cameleon is built on an extension of the petri net model for the description of how the Cameleon language executes a composition.