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Quickstart

JavaScript

The browser SDK. Tracks events, reads feature flags and experiments, and captures errors in any web app.

Package
@sheepit-ai/sdk-js
Runs on
ES2020 browsers

Get an API key

Don't have an account yet? Create one, free. Then open Settings → API Keys in the dashboard and copy the publishable key (lp_pub_…). It is safe to ship inside a browser or app bundle.

Install

bash
npm install @sheepit-ai/sdk-js

Initialize and send your first event

sheepit.ts
import { Sheepit } from "@sheepit-ai/sdk-js";

export const sheepit = Sheepit.init({
  apiKey: "lp_pub_...", // publishable key only
  appVersion: "1.4.2", // ties events to the release they came from
});

sheepit.track("signup_completed", { plan: "pro" });

Read a flag and an experiment

ts
// import { sheepit } from "./sheepit";
// Returns the default until the first config fetch lands.
const showNewCheckout = sheepit.flag("new_checkout", false) === true;

const { variant } = sheepit.experiment("pricing_page");

Identify users

ts
// import { sheepit } from "./sheepit";
// After login:
sheepit.identify("user_123", { plan: "pro" });

// On logout:
sheepit.reset();

Check that it worked

Open Events in the dashboard. Your signup_completed event shows up within about a minute: the SDK batches events and sends them every few seconds.

Worth knowing

  • flag() and experiment() return immediately. Until the first config fetch lands they return the default you pass; after that the SDK keeps config fresh in the background, so a flag change reaches a running page after a delay rather than instantly.
  • The browser SDK refuses secret and dev keys at startup, because shipping them would expose your project.
  • Self-hosted install? Add apiUrl: "https://<your-install>/api" to the config. The docs inside your install's dashboard show the exact value.
JavaScript quickstart | Sheepit