Case Study: Enterprise Architecture Leadership for Core Banking Platform Modernisation
Sector
Financial Services (Building Society)
Service
Architecture Managed Service
Engagement Length
4 Years
The Challenge
Building Society required enterprise architecture leadership to replace its legacy core banking platform and deliver a broader digital transformation agenda. The organisation also sought to unify its IT and Change functions, enhance architecture governance, and uplift technical maturity across the estate.
Objectives
- Lead the architecture vision and delivery for the core banking replacement and digital enablement programme
- Establish an in-house Enterprise Architecture function and develop internal capability
- Define IT strategy, application rationalisation, and cloud adoption roadmaps
- Deliver future-ready digital platforms including web, mobile, and HR systems
- Drive standardisation through architecture principles, modelling, and governance
- Partnered with the IT Director to merge IT & Change functions, and define IT & application strategies — reviewed by Gartner and presented to the Board
- Established the EA function from the ground up, including hiring and mentoring new domain architects
- Implemented Orbus iServer to manage current, transitional, and target architectures using a TOGAF-aligned meta-model
- Delivered architectural artefacts such as:
- Solution Vision, Architecture Impact Assessments, HLDs, LLDs
- Architecture Decision Register & Technical Debt Register
- Collaborated with vendors and system integrators to design and develop the Society’s target architecture
- Defined the Society’s Azure Cloud Strategy & Roadmap
- Led the creation and operation of the Architecture Review Board, serving as its Secretary
- Conducted market and competitor analysis using Gartner and Ovum research
Our Approach
The Outcome
- Successful implementation of a modern digital and architectural foundation across the organisation
- Core EA function embedded with sustainable internal capability
- Digital experience platforms launched, improving customer engagement and reducing reliance on legacy systems
- Recognised improvements in architectural maturity, governance, and business alignment
- Board-level confidence in IT and digital strategy strengthened through structured, documented approaches
