BizTalk and ESB migration to Azure – Phased and without disruption

Stable is not the same as safe

An ESB or BizTalk platform that has been running for years feels reliable. Yet the risk grows every year. License costs rise, support runs out, and the specialists who know the platform become scarce. Every connection to a modern, cloud-native system takes more effort than the last.

Waiting makes the problem bigger. The longer outdated middleware sits at the heart of your application landscape, the harder the transition becomes, and the more you depend on knowledge that is disappearing.

Phased migration, no big bang

We replace outdated middleware using the strangler fig approach: component by component, we rebuild connections on Azure Integration Services while the old platform keeps running. Every migrated connection first runs in parallel until it is fully tested and accepted. Only then do we switch over.

We start with a discovery: a joint analysis of all connections, dependencies, and risks in your landscape. This results in a migration plan with a clear sequence, planning, and priorities. So you know what to expect in advance, per phase and as a whole.

We build the new platform on proven Azure components: API Management as the central access layer, Logic Apps for orchestration, Service Bus for reliable messaging, and Azure Functions for transformation. Everything is deployed through automated pipelines and Infrastructure as Code, across separate environments for testing, acceptance, and production.

This ensures:

• Continuity, as old and new connections run in parallel until the switch is proven safe
• Predictability through a migration plan with clear phases and priorities
• Lower operating costs through pay-per-use instead of outdated licenses
• Future-proofing through a modular platform that new connections plug into easily

This is how we replaced the existing ESB platform for a European bank under strict compliance requirements: over 40 APIs went live, migrated without downtime, and were handed over to the in-house team, which can now move forward independently.

After the migration, we prefer to stay involved. With our Maintenance and Management services we keep the platform secure, up-to-date, and evolving under a multi-year agreement with SLA if desired.

Is your integration platform approaching the end of its life? We'd be happy to map out together what a migration means for your organization.