It is more an RTS than a 'classical' wargame, but you could do it in Warzone 2100. It is old for now (but it was very fun in 2000s). It could be fun for you today. There is a free and open source version : https://wz2100.net/ . Source: 6 months ago

It's free at wz2100.net and it's tiny, mere megabytes. Source: 11 months ago

There is also Warzone 2100 as a freeware RTS if you want something else to play https://wz2100.net/. Source: 12 months ago

I never had any problems running it on mine, but Warzone is a very old game. Are you using the latest version? https://wz2100.net/. Source: 12 months ago

Https://wz2100.net the best free and open-source rts ever. Optimised apple silicon processors. Source: about 1 year ago

Battlesnake is a bit like Robot Wars for programmers: by controlling your snake with code, battles with other snakes can be won or lost. - Source: dev.to / 25 days ago

Somewhat tangential, but RustConf last year had a talk[1] about a guy picking up Rust to get better times at Battle Snake[2]. [1] https://www.youtube.com/watch?v=-I1BfSpoWM0 [2] https://play.battlesnake.com/. - Source: Hacker News / 4 months ago

You could use a short response timeout (<1s) to make it impractical for human players to participate - for instance, that's what Battlesnake does (https://play.battlesnake.com/). Players provide an endpoint that follows the required API and their code never leaves their machines. - Source: Hacker News / 5 months ago

Battlesnake is a multiplayer game where a small server you write plays a survival-style snake game paired with snakes implemented by others. - Source: dev.to / over 1 year ago

Also for fun / to answer the passion part: how far can you get in https://warriorjs.com/ or https://play.battlesnake.com/ :) It's getting more advanced than you'd think. Source: over 1 year ago