As part of Apple Lisa’s 40th birthday celebrations, the Computer History Museum has released the source code for version 3.1 of Lisa OS under an Apple Academic License Agreement. With Apple’s blessing, the Pascal source code is available for download from the CHM website after completing a form.
Lisa Office System 3.1 dates back to April 1984, during the early Mac era, and was the Lisa equivalent of operating systems like macOS and Windows today.
The complete source package weighs about 26 MB and consists of more than 1,300 commented source files, neatly divided into subfolders indicating the code for the main Lisa operating system, various included applications, and the Lisa Toolkit development system.
First released on January 19, 1983, the Apple Lisa remains an influential and important machine in Apple history, pioneering the mouse-based graphical user interface (GUI) that came to the Macintosh a year later. Despite its innovations, the Lisa’s high price ($9,995 retail, or about $30,300 today) and lack of app support held it back as a platform. Within a year of its release, the similarly capable Macintosh slashed it in price. Apple released a major revision of the Lisa hardware in 1984 and then discontinued the platform in 1985.
The Lisa was not the first commercial computer to ship with a GUI, as some have claimed in the past (that honor goes to Xerox Star), but the Lisa operating system defined important conventions that we still use in window operating systems today, such as drag-and-drop icons, popup windows, the trash can, the menu bar, drop-down menus, copy-paste shortcuts, control panels, window overlays, and even one-touch auto-shutdown.
With the release of the LisaOS source, researchers and educators will now be able to study how Apple developers implemented those historically important features four decades ago. Apple’s Academic license permits the use and compilation of the source code “for non-commercial, academic research, educational teaching, and personal study purposes only.”
The Computer History Museum had previously teased the release of the code in 2018, but after spending some time reviewing it, they decided to delay its release until the computer’s 40th birthday, the perfect gift to honor the legacy of this important machine. .