Real-time collaborative coding in a web IDE

Abstract

This paper describes Collabode, a web-based Java integrated development environment designed to support close, synchronous collaboration between programmers. We examine the problem of collaborative coding in the face of program compilation errors introduced by other users which make collaboration more difficult, and describe an algorithm for error-mediated integration of program code. Concurrent editors see the text of changes made by collaborators, but the errors reported in their view are based only on their own changes. Editors may run the program at any time, using only error-free edits supplied so far, and ignoring incomplete or otherwise error-generating changes. We evaluate this algorithm and interface on recorded data from previous pilot experiments with Collabode, and via a user study with student and professional programmers. We conclude that it offers appreciable benefits over naive continuous synchronization without regard to errors and over manual version control.