TypeScript Action Creators with Redux Toolkit 2.0

Show how to define type-safe action creators using the createSlice function in Redux Toolkit 2.0, and how they integrate with TypeScript types for better development experience.
import { createSlice, PayloadAction } from '@reduxjs/toolkit';

// Define a type for the slice state
interface CounterState {
  value: number;

// Define the initial state using the CounterState type
const initialState: CounterState = {
  value: 0

export const counterSlice = createSlice({
  name: 'counter',
  reducers: {
    // Use the PayloadAction type to declare the contents of `action.payload`
    increment: (state) => {
      // Redux Toolkit allows us to write "mutating" logic in reducers. It
      // doesn't actually mutate the state because it uses the Immer library,
      // which detects changes to a "draft state" and produces a brand new
      // immutable state based off those changes
      state.value += 1;
    decrement: (state) => {
      state.value -= 1;
    // Use the PayloadAction type to automatically infer the action payload's type
    incrementByAmount: (state, action: PayloadAction<number>) => {
      state.value += action.payload;

// Action creators are generated for each case reducer function
export const { increment, decrement, incrementByAmount } = counterSlice.actions;
This TypeScript example creates a Redux slice for a counter feature using Redux Toolkit 2.0's createSlice. It defines type-safe action creators and state with the help of TypeScript's type system, ensuring that action payloads are correctly typed.