UltraCart API

The UltraCart REST API integration gives developers full programmatic control over every part of the platform. Items, orders, customers, subscriptions, fulfillment, checkout, coupons, gift certificates, and more all speak the same modern JSON-over-HTTPS interface, defined by a public OpenAPI spec and backed by official SDKs in six languages.

UltraCart was built API-first, so the interface your developers use is the same one our own apps and storefront features use under the hood. The API is organized around resource-oriented URLs with predictable request and response shapes, every endpoint is documented in the REST API reference, and the OpenAPI definition is available as a Postman collection and raw JSON schema for anyone who wants to generate their own client or load the spec directly into a tool like Insomnia, Stoplight, or Bruno.

Two authentication models cover the situations real teams run into. OAuth 2.0 is the right choice for third-party applications and partner integrations where you need fine-grained, per-user scopes and revokable access. Simple Key is the right choice for internal services and batch jobs where a stable, account-scoped credential is the cleanest fit. Both are managed from the admin UI, both are logged per-request, and both plug into the same resource endpoints without changing the shape of your code.

Official SDKs live on GitHub and are auto-generated from the OpenAPI spec, which means they stay in sync with the API as it evolves. PHP, Java, C#, JavaScript, Python, and Ruby are all first-class, each with concrete sample code for common tasks like listing orders, creating items, managing auto orders, and handling customer records. Generated clients handle serialization, pagination, and errors in idiomatic patterns for their language, so your integration code stays focused on business logic instead of HTTP plumbing.

For high-volume and event-driven patterns, the REST API pairs with UltraCart’s webhooks system. Webhooks push real-time events the instant something changes, and the API fills in the gaps for batch reads, administrative writes, and reflow-style historical backfills. That combination is what lets merchants build zero-lag ERP, WMS, CDP, and PIM integrations without writing a single polling loop. For getting-started material, the API introduction covers authentication, pagination, rate limiting, versioning, and errors, and the Simple Key tutorial walks through provisioning your first credential.