He earned a PhD in computer science (on the topic of natural language generation); and he and his wife Kathy had a son.
He eventually began working for Lawrence Livermore National Laboratory, where he recruited several of the researchers and programmers for a company, Lucid, Incorporated, he founded in 1984 and would leave in 1992.
The product the company shipped was a Lisp integrated development environment (IDE) for Sun Microsystems’ reduced instruction set computer (RISC) hardware architecture named SPARC.
Friction arose between the programmers and Stallman over how to handle graphical user interface (GUI) issues, and Lucid forked Emacs, and thus became mainly responsible for the birth of what would come to be called XEmacs.
After Gabriel left Lucid, Inc. for good, he became a Vice President of Development for ParcPlace Systems (1994–1995), and then a consultant, for, among others, Aspen Smallworks, before joining Sun Microsystems as a Distinguished Engineer.
[2] There, Gabriel was an influential contributor to the evolution of the open source software strategy,[3] culminating in publication of the book Innovation Happens Elsewhere.
[6] The citation reads: "For innovations in programming languages and software design, and promoting the interaction between computer science and other disciplines, notably architecture and poetry.