Just doing some random browsing on my system, and came across a Debian package called “open-adventure”. Finding my way to its home page at Eric Raymond’s site <http://www.catb.org/~esr/open-adventure/>, I discover that it is a project to modernize the source code for the original “ADVENT” game dating from 1976-1977, the one that originated the whole concept of text-based adventure games. The original code was written in Fortran; this one rewrites it all in clean, almost-idiomatic C (as opposed to automatically-translated GOTO-ridden C), and incorporates such innovations as using YAML as the source code for the maze format (translated to C structures at build time). It has been carefully regression-tested against the Fortran original(s) to ensure the gameplay is identical (and the few conscious deviations can be disabled if you want). The developers also kept in mind the possibility of porting the code further, to more modern languages like Python or Go. In the meantime, they have declared the project “finished” as of earlier this year, with all known bug reports closed and all compatibility tests passed.