# Little FORTRAN77 Chess engine

**URL:** <https://fortran-lang.discourse.group/t/little-fortran77-chess-engine/10865>\
**Category:** Uncategorized\
**Created:** [April 21, 2026, 4:49pm UTC](https://fortran-lang.discourse.group/t/little-fortran77-chess-engine/10865 "2026-04-21T16:49:31Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![Capinol](https://avatars.discourse-cdn.com/v4/letter/c/ce7236/32.png) [@Capinol](https://fortran-lang.discourse.group/u/Capinol)\
**Post date:** [April 21, 2026, 4:49pm UTC](https://fortran-lang.discourse.group/t/little-fortran77-chess-engine/10865/1 "2026-04-21T16:49:32Z")

</div>

Hi all!

Not a long time ago, I wondered, how it would be to write a chess engine in “pure” FORTRAN77 (no vendor extensions), so I decided to do it! It’s not very progressed right now - I’ve implemented the xboard protocol (UCI would be a pain, tried it), and move calculation for bishops, rooks and queens.

I already have a bit of experience in chess engine programming (made a chess engine in modern fortran), however I wanted to shake it up a little and instead of using an 8x8 matrix (noone does that anymore tho), or a bitboard (pretty sure that without vendor extensions, there’s no bitwise operations), so I used a 120size array.

I use Fort77 to compile it (pretty sure its standard compliant right now, if you find something non-compliant please tell me), which for some reason requires me to add a line after the final END statement (no idea why lol)

Anyways, feel free to check its development! - [GitHub - CapinolDev/GRP77: Chess engine in F77 · GitHub](https://github.com/CapinolDev/GRP77)