Strategy framework that features:

• Redo / Undo for everything ☑️
• Three modes
  • turn based mode, traditional one ☑️
  • real time mode, every action is executed on the fly ☑️
  • mix mode, plan in a turn, act simultaneously
• Pause / Resume ☑️
• Execute with a delay ☑️
• Serialize / Deserialize for easy save

Read wiki here.

• miniHexMap, a hexagon map editor

• Godot export

• Boardgame.io, a turn based framework supports multiplayer in JavaScript.