Open Banking Rails

Overview

Open banking gives regulated third parties the ability to retrieve account data and initiate payments directly from a customer bank account, with the customer explicit consent, under frameworks such as PSD2 in Europe and equivalent regimes elsewhere. Pay Engineers builds the technical integration layer that lets your product make use of these capabilities reliably, at scale and in a way that satisfies both regulators and the banks you connect to.

In practice, open banking connectivity is messier than the standards suggest. Every bank implements the underlying specifications with subtle differences, error handling varies enormously, and strong customer authentication flows must be handled gracefully across dozens or hundreds of institutions. We absorb that complexity so your product team can work against a single, normalised interface.

We work with both direct bank integrations and established aggregators, choosing the right mix based on your target markets, required coverage and tolerance for aggregator fees versus integration effort.

Who This Is For

• Fintechs building account-to-account payment initiation as an alternative to card payments
• Lenders, budgeting apps and financial management tools that need account information data with user consent
• PSPs wanting to offer open banking payments alongside card acceptance
• Businesses evaluating whether to integrate directly with banks or through an aggregator, and needing an informed technical assessment

What You Get

• Consent management flows that correctly capture, store and allow revocation of customer permissions in line with regulatory requirements
• AIS data normalisation, translating inconsistent bank responses into a single, predictable data model for your product
• PIS initiation flows covering single and, where supported, recurring account-to-account payments
• SCA handoffs correctly implemented so customers are redirected to and returned from their bank authentication flow without friction or data loss

Technical Approach

The integration layer is built in Laravel, using OAuth2 for the authorisation flows that underpin both account information and payment initiation consent. Where aggregators are used, we integrate against Open Banking APIs and, in relevant European markets, Berlin Group specifications, wrapping their differences behind a consistent internal interface so your product never needs to know which underlying method served a given bank.

Consent state, token lifecycles and renewal requirements are modelled explicitly, since consent expiry and renewal is one of the most common sources of broken user experiences in open banking products. Error handling is designed defensively, given how inconsistently banks report failures, timeouts and unsupported operations, so your product can degrade gracefully rather than surfacing raw upstream errors to end users.

Delivery Process

• Discovery of your target markets, required bank coverage and choice between direct integration and aggregator
• Consent and data model design covering AIS and PIS flows relevant to your product
• Sprint-based build of the integration layer, tested against sandbox environments from banks or your chosen aggregator
• SCA flow testing across representative banks to confirm redirect and authentication handling works smoothly
• Phased rollout starting with priority banks or markets before expanding coverage

Outcomes and Benefits

• A single, normalised interface for account data and payment initiation regardless of underlying bank quirks
• Lower payment acceptance costs compared with card rails for account-to-account use cases
• Compliant consent handling that stands up to regulatory and audit scrutiny
• A foundation that can expand bank coverage or add new open banking use cases without renegotiating your core architecture