The Cost of the Build Tax in Scientific Software

All compiled software systems require a build system: a set of scripts to invoke compilers and linkers to generate the final executable binaries. For scientific software, these build scripts can become extremely complex. Anecdotes suggest that scientific programmers have long been dissatisfied with the current software build tool chains. In this paper, we describe preliminary results from a case study of two projects to estimate the fraction of effort devoted to maintaining these scripts, which we refer to as the `build tax´. While estimates based on line counts are on the order of only 5%, estimates based on activity-related metrics suggest much higher values.