Downloading Acheron 0.9.0 for Mac from our website was free. The actual developer of this free Mac application is Michael Bohn. The program belongs to Developer Tools.
From the developer:
Acheron is a compiler that translates Common Lisp source code to JavaScript source code. The code can than be executed natively in any modern webbrowser. Programs are written in a subset of CL and after compilation executed in a webbrowser. This app has native functions that are written in JS and are the bridge between CL and JS.
You may want to check out more software for Mac, such as ChIDE, flex sdk 3 or MahJong Farmers, which might be similar to Acheron.