Looks pretty neat. My initial reactions:

- I don't like the `@kea(...` because it's another bit of JS syntax I hadn't heard of before. Though I do like decorators in Python, I just feel like I have learned enough of JS syntax to be productive and they seem to keep adding unnecessary stuff.

- There is still duplication between the action names and the reducers. When using Redux I now always use these two functions:

    function makeReducer(reducerObject) {
      return (state, action) => {
        if (Object.keys(reducerObject).includes(action.type)) {
          return reducerObject[action.type](state, action.value)
        }
        return state
      }
    }
    
    function makeActions(reducerObject) {
      const actions = {}
      Object.keys(reducerObject).forEach(name => {
        actions[name] = value => {
          return {type: name, value}
        }
      })
      return actions
    }

So I can just declare a single object of reducers and can infer the action names and creators from that e.g.

   const reducerObject = {
      increment(state, value) {
         return state + 1
      },
      decrement(state, value) {
         return state - 1
      }
   }
 
   const reducer = makeReducer(reducerObject)
   const actions = makeActions(reducerObject)