G95 is a free, portable, open source Fortran 95 compiler. It implements the Fortran 95 standard, part of the Fortran 2003 standard and some old and new extensions including proposed features for the Fortran 2008 standard like Co-array Fortran. When invoked with the -std=F source code is limited to the F programming language subset. It is primarily developed by Andy Vaught. In 2003, what is now gfortran, the GNU Fortran compiler, forked from G95.