  We present a system that allows a user to search a large linguistically
annotated corpus using syntactic patterns over dependency graphs. In contrast
to previous attempts to this effect, we introduce a light-weight query language
that does not require the user to know the details of the underlying syntactic
representations, and instead to query the corpus by providing an example
sentence coupled with simple markup. Search is performed at an interactive
speed due to an efficient linguistic graph-indexing and retrieval engine. This
allows for rapid exploration, development and refinement of syntax-based
queries. We demonstrate the system using queries over two corpora: the English
wikipedia, and a collection of English pubmed abstracts. A demo of the
wikipedia system is available at: https://allenai.github.io/spike
