Getting started

New to Appmax? This guide helps you understand the integration model and choose the right path for your scenario.

What is Appmax?

Appmax is a payments platform with gateway, anti-fraud, and acquiring built in. Integration happens through an App Store: you create an application, merchants install it in their stores, and from there you process payments on their behalf.

Appstore model vs direct API

If you're coming from other gateways (PagSeguro, Mercado Pago, Stripe), the model may feel unfamiliar. Here's the difference:

Traditional gateway	Appmax
You receive credentials directly by email	Credentials are generated through the installation flow
One API key per account	One pair of credentials per merchant who installs your app
Integrate directly with the API	Create an app in the Appstore → merchant installs → generates credentials → integrate

INFO

This architecture exists so that a single app can serve multiple merchants with data isolation and per-store credentials.

Choose your scenario

I want to integrate a custom checkout

You're a developer building a custom checkout for a merchant (or for yourself).

1. Create your application (private if it's for a single merchant)
2. Install and obtain credentials
3. Quickstart — first payment
4. Full integration example

I want to build a platform for multiple merchants

You're creating a platform (ERP, e-commerce, marketplace) that will be used by multiple merchants.

1. Create your application (public)
2. Installation — understand the 4-step flow
3. Authentication — understand app vs merchant credentials
4. Publishing to production

I want to add post-purchase upsell

1. Quickstart
2. Upsell API

Concepts you'll encounter

Concept	What it is	Where to learn
App vs Merchant credentials	Two credential pairs with different scopes	Authentication
Health check / Validation URL	Endpoint on your system that Appmax calls during installation to receive the external_id (UUID) that binds the installation to the store	Installation · Validate your URL
Webhook	Real-time notification of events (order paid, etc)	Webhooks
Sandbox vs Production	Two environments with different URLs	Environments
Values in cents	All monetary values are integers in cents	Concepts

Need help?

• FAQ — answers to frequently asked questions
• AI integration — connect Claude, Cursor, or another MCP agent to accelerate