Renamed to Lynq.js
The Checkout SDK is now published as @lynqpay/js, the package for all of Lynq’s browser components. Install @lynqpay/js and change your imports from @lynqpay/checkout-sdk; script tags still expose window.Lynq. @lynqpay/checkout-sdk is deprecated and receives no further releases.Changes
- Mastercard is reported as
mastercard in both validation events and payment results. mc is no longer a CardBrand value; if you compared against it, compare against mastercard.
- Checkout for a Payment Intent that was already paid or cancelled now fails with
CHECKOUT_SESSION_UNAVAILABLE (not retryable) instead of CHECKOUT_UNAVAILABLE. Check the payment’s status on your server before creating a new one.
- The SDK only follows
https: wallet redirects and 3-D Secure pages.
- README examples use test keys and the current version.
Script tag
Before going live
Test-mode 3-D Secure in this version is simulated in the browser. A later release completes it on the server; update to that release before taking live payments.Integration surfaces
- ESM npm package:
@lynqpay/checkout-sdk
- Version-pinned IIFE bundle for classic script-tag integrations
- Hosted Checkout mount, unmount, destroy, readiness, validation, result, and error APIs
- Internal Card authentication and wallet redirect handling
Developer experience
- TypeScript declarations and TSDoc for all public APIs
- Browser-only safeguard for server-rendered applications
- Stable error codes with retry guidance
- No source maps in the published package
Upgrade policy
Pin an exact SDK version in production. Before upgrading:
- Read the release notes for behavioural or type changes.
- Update the version in Test mode.
- Run the integration test plan.
- Deploy the tested version to production.
Patch releases fix compatible defects, minor releases add compatible features, and major releases may require integration changes.Last modified on November 2, 2026
