Stephen Curtis Johnson (born 1944) is a computer scientist who worked at Bell Labs and AT&T for nearly 20 years. He is best known for Yacc, Lint, spell, and the Portable C Compiler, which contributed to the spread of Unix and C. He has also contributed to fields as diverse as computer music, psychometrics and VLSI design. In the mid-1980s, he served as the head of the UNIX Languages Department (UNIX System V). Bell Labs colleague Alfred Aho suggested he look at Donald Knuth's work on LR parsing, which served as the basis for Yacc.
Silicon Valley
In 1986, Johnson moved to Silicon Valley, where he joined several startups, where he worked mostly on compilers, but also 2D and 3D graphics, massively parallel computing and embedded systems. The startups included Dana Computer, Inc., Melismatic Software, and Transmeta, which made low-power, Intel-compatible microprocessors. where he helped maintain the front end of the MATLAB programming language, for which he also built a lint product called M-Lint. He had met MathWorks founder Cleve Moler while working at a Silicon Valley startup and developed a "long-distance consulting relationship" with him in the 1990s.