byacc

Berkeley Yacc (byacc) is generally conceded to be the best yacc variant available. In contrast to bison, it is written to avoid dependencies upon a particular compiler.

Byacc was written around 1990 by Robert Corbett who is the original author of bison. Byacc is noted in Lex & Yacc by John Levine et al (O'Reilly, 1992) for its compatibility with the original yacc program.

Nowadays byacc is maintained by Thomas E. Dickey.