Thin async loader for the Overflow Payment Elements SDK. It injects the Overflow.js bundle from Overflow's CDN and gives you a typed, promise-based handle to the SDK.

Tiny, dependency-free loader (the SDK itself is served from the CDN)
First-class TypeScript types, generated from the SDK's source of truth
SSR-safe: loadOverflow(...) resolves null in non-browser environments
Loads the latest, always-patched build by policy (see Latest-only)

Full docs: https://docs.overflow.co · npm: https://www.npmjs.com/package/@getoverflow/payment-elements

Install

npm install @getoverflow/payment-elements

Quickstart (npm / bundler)

import { loadOverflow } from '@getoverflow/payment-elements';

const overflow = await loadOverflow('live_pub_...');

// `overflow` is null in SSR / non-browser contexts -- guard before use.
overflow?.card().mount('#card');

Importing the package eagerly starts downloading the CDN bundle as a side effect, so the SDK is in flight before your app mounts.

Defer the fetch with `/pure`

If you want to control exactly when the CDN request happens (for example, defer it until the checkout screen mounts), import from the /pure subpath. It has the same API with no import side effect -- nothing loads until you call loadOverflow().

import { loadOverflow } from '@getoverflow/payment-elements/pure';

async function mountCheckout() {
  const overflow = await loadOverflow('live_pub_...');
  overflow?.card().mount('#card');
}

This works the same way in React, Vue, Next.js, and other frameworks. In SSR frameworks, remember that loadOverflow(...) resolves null on the server, so call it from client-side code (an effect / event handler) and guard the result.

Script tag (no install)

You can also drop the SDK in directly with a script tag, then use the global Overflow constructor:

<script src="https://cdn.overflow.co/sdk/v1/payment-elements.js"></script>
<script>
  const overflow = new Overflow('live_pub_...');
  overflow.card().mount('#card');
</script>

Types for script-tag / CMS authors

A bare script tag gives you zero editor types. If you author in a CMS (WordPress, Drupal) or a plain HTML project and want window.Overflow typed, opt into the ambient declarations without bundling anything:

Add @getoverflow/payment-elements as a dev-only dependency and reference the ambient types from a *.d.ts (or the top of a TS file):
```
/// <reference types="@getoverflow/payment-elements/types" />
```
Or download global.d.ts and reference it from a local *.d.ts file in your project.

The ambient ./types entry is the opt-in that makes window.Overflow typed; it ships no JavaScript.

Latest-only policy

The loader and the documented script URL always point at the floating latest v1 build (https://cdn.overflow.co/sdk/v1/payment-elements.js). Pinning to a specific immutable version URL is deliberately not supported: serving only the latest build is a compliance and security requirement, so that no integrator can pin themselves onto a stale bundle that misses a security fix. There is no SRI / pinned-URL / setLoadParameters API.

If you have a hard requirement to self-host or pin a specific build, you do so on your own, outside this loader.

TypeScript

Types ship with the package. The SDK types (PublicKey, OverflowOptions, OverflowInstance, etc.) are generated from the SDK's single source of truth and kept in lockstep with each release, so the loader argument and return types always match the runtime constructor.

Versioning

The npm version mirrors the Overflow Payment Elements SDK version 1:1. Every published SDK release becomes a matching npm version and GitHub Release. Prereleases publish under the next dist-tag, so a bare npm install @getoverflow/payment-elements never resolves to a prerelease.

Contributing

The loader in this repo is open source (MIT). The core SDK served from the CDN is closed-source. Loader bug fixes, docs, and tests are welcome -- see CONTRIBUTING.md. Files under types/ are generated and should not be hand-edited.