Automatically repairing a buggy program is essentially a
search problem, searching for code transformations that pass a set of tests. Various search strategies have been
explored, but they either navigate the search space in an \emph{ad hoc} way
using heuristics, or systemically but at the cost of \emph{limited edit
expressiveness} in the kinds of supported program edits. In this work, we
explore the possibility of \emph{systematically} navigating the search
space without sacrificing \emph{edit expressiveness}. The key enabler of
this exploration is variational execution, a dynamic analysis technique
that has been shown to be effective at exploring many similar executions in large search spaces.
We evaluate our approach on IntroClassJava and Defects4J, showing that a systematic search
is effective at leveraging and combining fixing ingredients to find patches, including many high-quality patches and multi-edit patches.