Jihyeok Park is a Phd. candidate in School of Computing, KAIST, Korea. He is a main developer of SAFE, a Scalable Analysis Framework for ECMAScript, and JISET, a JavaScript IR-based Semantics Extraction Toolchain. Moreover, he is a main developer of JEST, a tool that performs N+1-version differential testing for both of JavaScript specifications and engines. Recently, he is working on developing other tools based on JISET.