An Experiment in Live Collaborative Programming on the Croquet Shared Experience Platform

This paper describes our experiences in building a live collaborative programming environment on top of the JavaScript version of the Croquet shared experience platform. Croquet provides a clean substrate for building real-time collaborative applications. We created an application framework that supports live programming, and used that framework to build the Greenlight collaborative application, then in turn, modified it to do live programming experiments. The environment allows multiple users to modify the running application from within, with changes taking effect immediately. The experiment was inspired by earlier work including Douglas Engelbart’s oN-Line System (NLS) and the Kansas system in Self. Analogically, the system is like the Smalltalk environment made collaborative. In this paper we explain the Croquet architecture, its library and framework, and the Greenlight application used to make the live programming environment. The standard version of Greenlight is available at https://croquet.io/greenlight, and the modified demo system is available at https://croquet.io/scripting.