is a free web application framework created by David Heinemeier Hansson, now a partner at Basecamp. It was originally used to make 37signals' first product, Basecamp, and was then extracted and released as open source in 2004. Hey Hey (stylized in all-caps as HEY) is a premium email service started in June 2020 by Basecamp. A few days after its release, Apple gave notice to Basecamp to create an in-app subscription option for Hey, threatening to pull the service's iOS app from the App Store. Works Jason Fried and David Heinemeier Hansson published several books under the 37signals name. Defensive Design for the Web: How to improve error messages, help, forms, and other crisis points, New Riders Press, 2004 Getting Real: The Smarter, Faster, Easier Way to Build a Successful Web Application, 37signals, 2006, Rework (2010, RandomHouse) became a New York Times best seller. Remote: Office Not Required (2013, RandomHouse), which is about allowing employees to work from remote offices, was also a New York Times best seller. The book was about 37signals' experience with a largely remote workforce. It Doesn't Have to Be Crazy at Work, October 2, 2018, References External links Remote companies Privately held companies based in Illinois Companies based in Chicago Software companies established in 1999 1999 establishments in Illinois Project management software