Integrate your game engine.

Keep payment UI in a supported browser host and fulfillment on your game server.

Unity WebGL host-page path#

The public Unity path uses @playmos/sdk alongside the WebGL build. Install it in a Vite host app, put a Buy button and payment-status output beside the canvas, and use the browser purchase example. Open the host in a browser; Unity Editor Play Mode does not exercise this payment flow.

Create a browser hostTerminal

npm create vite@latest playmos-unity-host -- --template vanilla-ts
cd playmos-unity-host
npm install
npm install @playmos/sdk@0.3.20
npm run dev

Keep your Unity build on that page. If you pass receipt IDs to the engine, treat them as display/input only: the trusted game server verifies them before granting an item. Never put an sk_ key in Unity assets, JavaScript or a bridge message.

Choose the game-server language#

Use the published .NET package, Node SDK, Python package or direct HTTP for server verification. The language guide lists pinned versions and each surface’s limitations. A thin server client’s confirmed flag alone is not sufficient to match a purchase or deduplicate a grant.

Engine availability#

Surface	Current public path
Web / Phaser / HTML5	Bundled JavaScript SDK and a trusted backend.
Unity WebGL	Browser host + server verification. com.playmos.sdk is not a public UPM install.
Godot HTML5	No public Playmos engine package; use a separately integrated web host if building your own adapter.
Unreal	No public Playmos engine package; a system-browser flow needs your own secure callback/session design.
Three.js	Use the web SDK as application code; there is no separate engine package.
Native mobile, subscriptions, Bridge virtual accounts	No public supported SDK/product path in this iteration.

Publisher release review and the portal’s iframe launch are separate from engine SDK availability. A local WebGL build is not a published listing.

Keep buildingYour first payment

Unity host · payment controlsTypeScript

import { Playmos } from '@playmos/sdk';
 
export function bindSandboxPurchase(button: HTMLButtonElement, output: HTMLElement) {
  const client = new Playmos({ apiKey: 'pk_test_playmos_sandbox', settle: 'server' });
  const storageKey = 'playmos-demo-purchase';
  button.onclick = async () => {
    button.disabled = true;
    const key = sessionStorage.getItem(storageKey) || crypto.randomUUID();
    sessionStorage.setItem(storageKey, key); // Persist BEFORE sending.
    try {
      const payment = await client.pay({
        gameId: 'game_sandbox_iap', amount: '0.01',
        sku: 'extra-life', playerId: 'sandbox-player', idempotencyKey: key,
      });
      sessionStorage.setItem(`${storageKey}:id`, payment.id);
      const receipt = await client.verify(payment.id);
      output.textContent = JSON.stringify(receipt, null, 2);
      // Display only. Your backend owns verification and a single item grant.
    } catch (error) {
      const id = (error as { detail?: { paymentId?: unknown } }).detail?.paymentId;
      if (typeof id === 'string') sessionStorage.setItem(`${storageKey}:id`, id);
      output.textContent = error instanceof Error ? error.message : 'Request failed.';
      // Once an ID exists, recover with client.verify(id), not another purchase.
    } finally { button.disabled = false; }
  };
  // Reset the saved key and ID only when intentionally starting a NEW purchase.
}

IN THIS GUIDEUnity WebGL host-page path Choose the game-server language Engine availability Try it in the playground