Longitudinal analysis of long-timescale open source repository data

One of the more unique features of open source software development is the continuity of projects over large time scales and incremental development efforts. For this reason, the open development process provides an interesting environment for investigation of the software development process. The problems of data collection and analysis of two particular long-running repositories, the X Window System and the Nickle Programming Language, are considered here as instructive examples. The use of uniform software tools (CVS/RCS) with open formats and interfaces makes it possible to collect data that provide unique analysis opportunities.