This paper introduces GKC, a resolution prover optimized for search in large knowledge bases. The system is built upon a shared memory graph database Whitedb, enabling it to solve multiple different queries without a need to repeatedly parse or load the large parsed knowledge base from the disk. Due to the relatively shallow and simple structure of most of the literals in the knowledge base, the indexing methods used are mostly hash-based. While GKC performs well on large problems from the TPTP set, the system is built for use as a core system for developing a toolset of commonsense reasoning functionalities.