Andrew Johnston: Architecture and Consultancy Services

Case Study - Yodel Delivery Network Limited (June 2015 – February 2017)


Enterprise Architecture for a major core systems replacement project

Key Outcomes

Delivery of a comprehensive set of reference architectures for the new solution

Key Challenges

Dysfunctional internal team structures, multiple changes of technical and supply direction.

Key Technologies

Oracle SOA Suite, Microsoft stack, Linux and various open source technologies including OpenLDAP


Yodel, a UK parcel delivery company, was created out of the merger of two disparate companies, and has an IT estate characterised by significant duplication and fragmentation, relying on core systems using ageing legacy technologies. The company decided to replace these with a streamlined and consolidated solution based on more modern approaches.

I was engaged to support a small existing Enterprise Architecture team by documenting and guiding the architecture of the new core system and its integration. When the original package-based approach was abandoned in favour of an internal Oracle-based development, I helped create a strong service- and event-based architecture capable of managing Yodel’s significant business volumes in real time. I documented these in a set of comprehensive reference architectures, encompassing all layers of the solution and extending from top-level principles to key design patterns and standards.

One particular challenge was to ensure that the solution met high business expectations in terms of performance and reliability, in a highly cost-constrained physical environment. I led the definition of a comprehensive set of non-functional requirements, and guided an inexperienced team to develop models establishing the suitability of the proposed designs.

In addition, I designed an identity management solution for external users (using OpenLDAP), conducted an independent review of a problematic billing system, and supported the development of Yodel’s first customer mobile application.

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