Follow the steps below to integrate Castled JS SDK with your Nextjs app.

Install the SDK

To install the SDK via npm, run the following command:

npm install castled-js-sdk --save

Integration with the project

  1. Create the following file in the pages directory within your project

    import { useEffect, useState } from "react"
    const useCastledAnalytics = (): any => {
      const [analytics, setAnalytics] = useState<any>()
      useEffect(() => {
        if (!analytics) {
          const initialize = async () => {
            const castledanalytics = await import("castled-js-sdk")
            castledanalytics.load("<APP-ID>", "<SERVER-URL>")
            castledanalytics.ready(() => {
              console.log("Castled analytics initialization complete")
          initialize().catch((e) => console.log(e))
      }, [analytics])
      return analytics
    export default useCastledAnalytics
    • APP-ID is a unique id associated with your Castled workspace. It can be found in the Castled dashboard at Settings > Api Keys.
    • SERVER-URL is the cluster url where the events are initially send to. is the default value of this url.
  2. Sample code snippet below shows how you would use the useCastledAnalytics method created in previous step for tracking user events.

    import { useEffect } from "react"
    import useCastledAnalytics from "./useCastledAnalytics"
    const EventTrackingDemo = () => {
      const analytics = useCastledAnalytics()
      const identify = () => {
        // Track user traits
          "user-12345", // unique user-id
            // user traits
            fname: "hello",
            lname: "user",
            age: 34,
            email: "",
      const track = () => {
        // Track user events and event properties
        analytics?.track("Added to Cart", {
          value: 30,
          currency: "USD",
          item: "product A",
      return (
        <div style={{ padding: "20px" }}>
          <h1>Event Tracking Demo</h1>
          <button onClick={identify}>Identify Me</button>
          <button onClick={track}>Add to Cart</button>
  3. Once you integrate the SDK and add the code snippets to enable tracking, you will be able to verify the tracking api calls in your browser by inspecting network calls. For e.g. following image shows an instance of identify call.

    Identify call