[zzo38computer]

That is not bad. Even if the scripts are disabled, or if images are disabled, or if the server is unreachable, a link to it is still usable, since the URL contains the FEN code. However, a suggestion is maybe you might want to add <noscript><img...> so that if images are enabled but scripts are disabled and the link is not directly to the picture, that it is still displayed without having to alter the URL (although even the way it is now, the instructions for altering the URL are available on that web page, so it isn't so much of a problem).

My "Farbfeld Utilities" software also can be used for making a chess board, if you have all of the pieces pictured in one file. So when you want to do it locally rather than adding a link on a web page, this can be done. (You can alter the colours and metrics below as needed)

  ff-chess 8 8 32 E5E5D7 001000 \
   | ff-composite <(pngff < pieces.png \
   | ff-text +PNBRQKpnbrqk 32 32 `sed 's.7.43.g;s.6.33.g;s.5.32.g;s.4.22.g;s.3.21.g;s.2.11.g;s./. .g' < board.fen`) 0,0,0 \
   | ff-border 0020FF 8