SDKs & Libraries

TypeScript SDK

Packages: @peakgateway/sdk (server and browser-runtime client) and @peakgateway/web-sdk (browser checkout)
Targets: Node.js 18.17 or later and modern browser and worker runtimes; ESM
Runtime dependencies: none for @peakgateway/sdk
Contents: the public merchant and partner API only. Peak's staff, agent and terminal-fleet operations are not in these packages.

retired @gateway scope. Do not install @gateway/sdk from public npm.

The package exposes two top-level clients:

GatewayAdminClient for management, reporting, subscription, and webhook APIs on the api.* boundary
GatewayPayClient for hosted checkout and payment-facing APIs on the pay.* boundary

import { GatewayPayClient } from '@peakgateway/sdk'

const client = new GatewayPayClient({
  clientId: process.env.PEAK_CLIENT_ID!,
  clientSecret: process.env.PEAK_CLIENT_SECRET!,
  environment: 'production',
})

// Persist this key and the original request before dispatch; reuse on recovery.
const checkoutCreateKey = process.env.CHECKOUT_CREATE_KEY!
const session = await client.checkoutSessions.create({
  amount: 2500,
  currency: 'USD',
  locationId: process.env.PEAK_LOCATION_ID!,
  successUrl: 'https://example.com/checkout/success',
  cancelUrl: 'https://example.com/checkout/cancel',
}, checkoutCreateKey)

console.log(`Send the shopper to ${session.checkoutUrl}`)

The processing service's typed sale and authorization operations are not part of the public SDK. Use hosted checkout, or an explicitly documented card-present boundary, to take a payment.

Do not place clientSecret in browser code. Use a backend or a checkout session token for shopper-facing flows.

See the TypeScript SDK reference for modules, result types, OAuth behavior, and webhook verification.

Kotlin and Android SDKs

The Kotlin artifact namespace is com.myriad.gateway:

Artifact	Consumer
`gateway-sdk-core-kmp`	JVM and Kotlin Multiplatform core client
`gateway-sdk-core-kmp-android`	Android variant of the KMP core
`gateway-sdk-android`	Self-contained Android client and terminal/runtime surface
`gateway-sdk-android-nearpay`	Optional NearPay runtime used with `gateway-sdk-android`

See the Kotlin SDK reference and Android SDK reference for configuration and platform requirements.

Reliability guidance

Reuse a client instance so its token cache and HTTP resources are effective.
Supply idempotency keys only on operations that document them.
Retry transport failures only through the SDK's documented policy. Never blindly retry an unknown payment outcome; reconcile it first.
Handle approved, declined, in-doubt, and API-error results explicitly.
Verify webhook signatures before acting on webhook payloads.