David Ungar

David Michael Ungar is an American computer scientist who co-created the Self programming language with Randall Smith. He earned his doctorate in computer science at the University of California, Berkeley in 1985 under David Patterson, with a dissertation on the design and evaluation of a high-performance Smalltalk system that won the 1986 ACM Doctoral Dissertation Award. He taught at Stanford from 1985 to 1990, joined Sun Microsystems in 1991 and became a distinguished engineer, then worked at IBM Research from 2007 to 2017 and at Apple from 2017 to 2022, where he sped up Swift compilation. His 1984 paper on generation scavenging introduced generational garbage collection and won a retrospective ACM SIGSOFT Impact Paper Award in 2008. He received the Dahl-Nygaard Senior Prize in 2009, holds over 20 US patents and was named an ACM Fellow in 2010.