Is your software not in the list of ready-made integrations, or are you building an application that needs to send and receive invoices via Peppol? Then you can integrate directly with the eConnect Procurement Service Bus (PSB). The PSB is the technical system behind all eConnect integrations, accessible via psb.econnect.eu. The eConnect platform (platform.econnect.eu) is the customer interface where you create connection keys and manage your settings, among other things. The PSB offers three connection methods: a modern REST API, SFTP and HTTPS.

Which method fits best depends on your architecture, security requirements and expected volume. For each method, you can find the technical documentation on the PSB developer portal.

The most commonly used method for new integrations. The PSB REST API provides endpoints for sending, receiving and managing invoices, orders and responses. Authentication is handled via OAuth2, with two available flows: Resource Owner Password Credentials and Client Credentials. Tokens are requested via POST /connect/token on identity.econnect.eu. Optionally, a Subscription-Key header can be included for organisation-specific access.

Suitable for: SaaS applications, web applications, microservices and modern architectures.

Documentation: PSB API & Swagger UI: interactive API documentation, OpenAPI specification and Swagger Editor.

Exchange files through a secured SFTP connection. The PSB supports two flows: From SFTP (periodically fetching files from your SFTP server) and To SFTP (pushing documents to your server upon receipt). Both flows are configured through SFTP hooks in the PSB.

Suitable for: enterprise environments with batch processing, ERP systems like SAP and Unit4 ERP CR.

Documentation: PSB API & hooks: search for SFTP hooks in the Hook endpoints.

A direct HTTPS connection for exchanging invoices. The PSB receives documents via HTTPS POST and delivers them through webhooks or HTTPS inbound. Supports IP whitelisting and OAuth2.

Suitable for: enterprise integrations with specific security requirements.

Documentation: PSB API & webhooks: HTTPS inbound/outbound and webhook configuration.

Technical: The PSB communicates internally via the Peppol AS4 protocol with other Access Points. This is not a connection method you choose as a customer; it is used automatically when you send invoices via Peppol.

For any integration with the PSB, you need:

• An eConnect account with at least a Professional subscription for SFTP and HTTPS (custom integrations require an Enterprise subscription)
• OAuth2 credentials (client_id and client_secret) for the PSB REST API
• For enterprise protocols: a subscription key via the sales department

The fastest way to get started is through the REST API: open psb.econnect.eu, explore the Swagger UI and make your first API call. More guidance can be found in the API & integration section of this documentation.

For SFTP or HTTPS integrations, contact the eConnect sales department for an intake meeting. During that meeting, the technical details, expected volume and security requirements are discussed. The technical specifications are available in the PSB API documentation.

Tip: Are you building an integration for a software package used by multiple customers? Then get in touch with the eConnect partner team. As a partner, you can build the integration once and make it available for all your customers.

Ready to get started? Open the PSB API documentation or read the PSB overview for more context.

• PSB API overview
• Overview: how can you connect software with eConnect?
• Create connection keys in eConnect
• Set up and secure webhooks