English: Although PHP has several features that allow engineers to be extremely productive in it, it also has several rough edges and pitfalls that cause problems (and often give the language a bad name). This talk will introduce Hack, Facebook's dialect of PHP. Hack keeps most of the PHP language -- all of the parts that make engineers so productive -- but sands down several of the more problematic sharp edges. It also introduces several new features, such as a simple yet extremely powerful syntax for asynchronous IO, to make the language even more effective for existing PHP programmers and newcomers alike.