Open-source poker hand calculator 
1. https://github.com/bartoszputek/poker-master-tool   demo: https://pokermastertool.bartoszputek.com/
2. https://github.com/geres99/TexasHoldemOddsCalculator demo: https://geres99.github.io/TexasHoldemOddsCalculator/
3. https://github.com/openpokertools/openpokertools.com demo: https://openpokertools.com/

solver
1. https://github.com/kmurf1999/HoldemSolver

game engine
1. https://github.com/wzdwc/TexasPokerGame
2. https://github.com/kielnevec/crypto-poker
3. https://github.com/norkator/poker-pocket-backend demo: https://pokerpocket.nitramite.com/
4. https://github.com/SirRender00/texasholdem 
*5. https://github.com/geobalas/Poker demo: http://dev.tableflippoker.com/

cards
1. https://github.com/Tairraos/Poker.JS
demo:
https://tairraos.github.io/Poker.JS/demo/sprite.html
https://tairraos.github.io/Poker.JS/demo/demo.html

Hands replay
https://github.com/vikcch/riropo demo:https://replayer.winningpokerhud.com/?id=500