Traditionally, writing parsers has been hard, involving arcane tools like Lex and Yacc.An alternative approach is to write a parser in your favourite programming language, using a "parser combinator" library and concepts no more complicated than regular expressions. In this talk, we'll do a deep dive into parser combinators. We'll build a parser combinator library from scratch in F# using functional programming techniques, and then use it to implement a full featured JSON parser.