We describe a methodology for precise quantitative measurement of technolog
y impact on software change effort. The methodology employs measures of sma
ll software changes to determine the effect of technology. We illustrate th
is approach in a detailed case study on the impact of using two particular
technologies-a version-sensitive source code editor and a domain-engineered
application environment-in a telecommunications product In both cases, the
change effort was reduced. The methodology can precisely measure cost savi
ngs in change effort and is simple and inexpensive, since it relies on info
rmation automatically collected by Version control systems.