  The promise of search-driven development is that developers will save time
and resources by reusing external code in their local projects. To efficiently
integrate this code, users must be able to trust it, thus trustability of code
search results is just as important as their relevance. In this paper, we
introduce a trustability metric to help users assess the quality of code search
results and therefore ease the cost-benefit analysis they undertake trying to
find suitable integration candidates. The proposed trustability metric
incorporates both user votes and cross-project activity of developers to
calculate a "karma" value for each developer. Through the karma value of all
its developers a project is ranked on a trustability scale. We present JBender,
a proof-of-concept code search engine which implements our trustability metric
and we discuss preliminary results from an evaluation of the prototype.
