Overview

Welcome to the Payment Gateway documentation. The Payment Gateway is a self-hosted, enterprise-grade platform for accepting online payments, managing invoices, and handling complex tax compliance — all under your own infrastructure and brand.

One of the main strategic advantages of the platform is continuity. Your payment history, invoice records, and buyer-facing billing data stay in your own system even when payment provider terms, risk decisions, or commercial models change.

Core Capabilities

• Multi-Provider Payments: Accept cards, direct debits, and wire transfers through a unified interface (Stripe, GoCardless, Wise Transfers, and Wire Transfer).
• Payment Data Boundary: Card input is handled through provider-hosted or tokenized flows; the gateway does not store raw PAN/CVC values.
• Persistent History and Invoicing: Keep one payment and invoice history across provider changes, with gapless numbering, PDF invoice customisation, and support for ZUGFeRD, Peppol, and XRechnung workflows. Finalized buyer documents are downloaded through the customer portal.
• Multi-Tenant Organizations: Full role-based access control for teams with a dedicated Admin Panel.
• Advanced Tax Engine: Native EU VAT OSS/IOSS, UK VAT, US Sales Tax, and Canadian GST/HST with temporal rate scheduling.
• Customer Portal: A branded, self-service portal for buyers to access invoices, preview upcoming recurring charges, and manage subscription cancellation on your configured hosted portal domain or your own mapped portal domain.

Portal Roles

• Operator License Portal: Your licensing and deployment workspace, such as payment-gateway.app in the first-party deployment, where operators manage licenses, registry access, and account onboarding.
• Customer Portal: Your buyer-facing invoice and subscription workspace, such as secure.payment-gateway.app in the first-party deployment, where end customers authenticate with OTP and manage their billing relationship.

Both portals are deployment-specific. Product documentation uses the first-party domains only as examples; self-hosted customers can map their own domains and branding.

Application hostnames on the hosted stack (dashboard, api, secure, webhook under payment-gateway.app) are summarized in Hostnames & DNS conventions. Registry and licensing endpoints (registry.payment-gateway.app, registry-auth.payment-gateway.app) are covered there too.

Operations

• Flexible Deployment: Docker Compose or rootless Podman on Linux, with automated upgrade tooling.
• Data Lifecycle Controls: Organization-level retention settings plus GDPR-oriented backup and restore runbooks.

Commercial Model

• One Implementation: Integrate once against your own gateway surface and keep providers replaceable behind it.
• Custom Provider Additions: Additional payment providers can be added for 100 EUR one-time per provider.
• Invoice Output Flexibility: PDF invoice customisation and related billing adjustments are available for teams that need tailored output.

Getting Started

• Hostnames & DNS conventions — Hosted *.payment-gateway.app layout, env variables, registry hosts.
• Self-Hosted Installation — Install the stack with Docker Compose, required domains, license registry access, activation, and updates.
• Quick Start — Set up your first hosted checkout flow.
• Server integration checklist — Hostnames, webhooks, Admin API, IPN.
• Features & User Guide — How to use the platform as a merchant.
• API Reference — REST API documentation for programmatic integration.
• Architecture & Components — How the system fits together technically.
• Deployment — Self-hosting installation guide.