UCSD Pacal - Forerunner of Java

Java's model of "run everywhere" portability and its implementation via a byte-code psuedo-machine interpreter were inspired in-part by the UCSD Pascal System - a highly portable operating system and programming environment developed under Ken Bowles' Project in the late-1970s. By 1980, UCSD Pascal ran on essentially every available type of computer and had 10,000 users.

As an early member of the project, we had primary responsibility for the second and later versions of the lead interpreter implementation, for the DEC PDP/LSI-11. We also developed the native compiler code generator control-flow validation suite, the Texas Instruments TI990 native-code generator, and dozens of device drivers (often at the rate of two a day).

Later, as a principal in Volition Systems, we performed analysis and feasibility study of a Modula-2 compiler implementation for LSI-11/UCSD Pascal and Z80/CP-M. We also consulted on design of a microcoded hardware implementation of a psuedo-machine for Modula-2 and UCSD Pascal - a precursor of Sun's new MAJC chip.