Zusdux

The forbidden love child of Redux and Zustand ❤️‍🔥👶

What is Zusdux?

Zusdux is a type-safe state management library that combines the best of both worlds from Redux and Zustand. It has a Redux Toolkit-like API, but with Zustand's reduced boilerplate and simplicity. It also has a built-in support for React!

API

The API is pretty similar to what you'd find in Redux Toolkit's createSlice function, with a leaner signature, and without the need for providers or messing up with async thunks - similar to Zustand.

It has a single function, called createStore, which returns an object with getState, setState, subscribe, useStore, and actions properties.

Usage

First, you create a store with the createStore function. It takes an object with initialState and actions properties:

• initialState - It's... well... the initial state of your store

• actions - An object containing a list of actions that can be performed on the state. The actions can be either synchronous or asynchronous, they can take any number of arguments, while the first one is a set function that allows you to update the store's stat. The set function can accept either a new state object that will be shallowly merged with the current state, or a function that receives the current state and returns the new state. (See Zustand's documentation for more info)

// store.ts
import { createStore } from 'zusdux';

export const { actions, getState, setState, subscribe, useStore } = createStore(
  {
    initialState: {
      name: 'counter',
      count: 0,
      isLoading: false,
    },
    actions: {
      increment: (set) => {
        set((prev) => ({
          ...prev,
          count: prev.count + 1,
        }));
      },

      incrementBy: (set, by: number) => {
        set((prev) => ({
          ...prev,
          count: prev.count + by,
        }));
      },

      incrementAsync: async (set) => {
        set({ isLoading: true });

        await new Promise((resolve) => setTimeout(resolve, 100));

        set((prev) => ({
          ...prev,
          count: prev.count + 1,
          isLoading: false,
        }));
      },

      setName: (set, firstName: string, lastName: string) => {
        set({ name: firstName + ' ' + lastName });
      },
    },
  },
);

Each "store action" is then converted to a "user action" under the store object, which will update the store's state when called:

actions.increment();
actions.incrementBy(5);
await actions.incrementAsync();
actions.setName('new', 'name');

In addition, you can access the current store's state with the getState function, and update it with the setState function:

const currentState = getState(); // { name: 'counter', count: 0 }

setState((prev) => ({
  ...prev,
  count: 5,
}));

const updatedState = getState(); // { name: 'counter', count: 5 }

Similar to Redux, you can also subscribe to the store's state changes:

const unsubscribe = subscribe(() => {
  console.log('Current state:', getState());
});

unsubscribe();

And similar to Zustand, you can use the store within your React components:

// Counter.tsx
import { actions, useStore } from './store';

export const Counter = () => {
  const { name, count, isLoading } = useStore();

  return (
    <div>
      <h1>{name}</h1>
      <p>{isLoading ? 'Loading...' : 'Not loading'}</p>
      <p>Count: {count}</p>

      <button onClick={actions.increment}>Increment</button>

      <button onClick={() => actions.incrementBy(5)}>Increment by 5</button>

      <button onClick={actions.incrementAsync}>Increment async</button>

      <button onClick={() => actions.setName('new', 'name')}>Set name</button>
    </div>
  );
};

You can also provide a selector to the useStore function to select a specific part of the store, similar to what you'd do with Redux's useSelector

const count = useStore((state) => state.count);

This way, your component will only re-render when the selected part of the store changes.

As you might've noticed, we don't need a provider at all! 🥳