Rex Jaeschke
Computer Consultant
I am a consultant, author, and a leader and designer of seminars, specializing in the programming languages C, C++, C#, Java™, and Visual Basic .NET™. I am also involved in a number of U.S. and international standards committees.


To see my personal blog (on which I post a 4-8-page essay each month) click here.


Mid-2017, I was invited to consider taking on the chairmanship of the Ecma standards committee TC39, which defines the JavaScriptâ„¢ language. As the idea interested me and I had the time for another project, I attended the September meeting as an observer. I came away as the acting chair! I've since chaired three 3-day meetings (we meet every two months), and have been appointed the chair. This is my first time chairing a group as large as 50, including some who join via audio-video.

As part of my work for Facebook, I wrote the first formal specification for the PHP language. This spec is available to the public at I also wrote one for Hack, Facebook's strongly typed language that is built on PHP. That spec is available at