Simon Marlow is a developer at Microsoft Research in Cambridge. He has been one of the two lead developers of the Glasgow Haskell Compiler over most of its lifetime. Simon is responsible in particular for GHC's highly-regarded multicore runtime system. When he is not developing GHC, Simon also contributes to the functional programming languages research community, and has a string of papers on subjects ranging from garbage collection to language design. In recent years Simon's focus has been on making Haskell an ideal programming language for parallel and concurrent applications, both by developing new programming models and building a high-quality implementation.