Empirical studies on code require standardized datasets of significant size extracted from real-world programs in order to be reproducible and generalisable. We argue that there is a need for such data sets that are executable and can therefore be used for experiments using static and dynamic analysis. A harness for such a data set should have high coverage in order to facilitate the construction of comprehensive models of program execution.We present XCorpus, a set of 76 executable, real-world Java programs, including a subset of 70 programs from the Qualitas Corpus. XCorpus uses a harness that is a combination of built-in and generated test cases, resulting in a branch coverage that is significantly better than what is available from DaCapo.