configureStore

The problem

createStore + applyMiddleware(thunk) + combineReducers + composeWithDevTools is four packages and a footgun. Forget thunk and dispatch(fn) throws. Forget combine and the second slice overwrites the first.

The pattern that fixes it

configureStore({ reducer, middleware }) is the factory. reducer: { a, b } is combineReducers. Default middleware includes thunk. DevTools is on by default. That is why RTK exists: setup used to be the hard part.

Keep learning

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• Next: createAction
• Related: createAction
• Related: extraReducers + matchers
• Related: createEntityAdapter
• Related: createSelector
• Related: createListenerMiddleware
• Related: combineSlices / inject

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