IT Systems Architect Principal

Job Description

At BT International, our purpose is to keep the world connected. As part of BT, we build on almost 180 years of innovation and expertise to deliver secure connectivity and digital services to some of the world’s leading multinational businesses and organisations. Our customers trust us to safeguard their data, drive their digital transformation and keep their businesses running. With colleagues on the ground across the world and supporting customers wherever they need to operate, BT International offers a truly global experience. Whether it’s about providing cloud connectivity, helping organisations collaborate, or enabling innovation in cybersecurity and digital services, you’ll be part of a team that shapes how businesses succeed in a world that is being transformed by AI. If you have the drive and ambition to make an impact on a global stage, BT International is where it happens.

Why this job matters

The IT Systems Architect Principal is central to BT International's ability to deliver products at velocity while maintaining operational excellence. This role owns the platform transformation and vendor rationalization strategy that directly impacts product team autonomy, cost efficiency and speed to market. This architect ensures every architectural decision drives product velocity and long-term value. This position leads vendor rationalization, establishes composable platform patterns and collaborates with senior stakeholders. By aligning platform architecture with business imperatives and group strategy, the role ensures BT International remains competitive, agile and customer-focused in a rapidly evolving global landscape.

What you’ll be doing

1. Define and lead the architectural strategy for IT systems and BSS modernization across BT International, establishing the target state architecture that guides system rationalization, vendor consolidation and platform transformation initiatives

2. Own the application portfolio rationalization roadmap, making strategic keep/modernize/retire decisions based on technical fitness, business value and architectural alignment while managing stakeholder expectations

3. Establish API-first integration architecture that decouples BSS systems from each other and from product applications, creating clear service boundaries that enable independent team delivery and reduce system dependencies

4. Lead vendor rationalization strategy across SaaS platforms, on-premise systems and cloud-based solutions, reducing vendor dependencies through strategic build vs buy decisions and phasing out unnecessary third-party systems in favor of composable in-house capabilities

5. Champion modern architecture patterns including microservices, event-driven integration and API gateways that enable incremental transformation without big-bang rewrites

6. Collaborate with Data & AI architects to ensure IT systems generate high-quality data with proper lineage and governance, enabling analytics and AI capabilities across the platform

Skills and Experience

The skills you’ll need to succeed

Strategic Architecture Leadership – Proven ability to define and communicate architectural vision for complex enterprise landscapes, with track record driving large-scale modernization programs in regulated industries

BSS Domain Expertise – Deep understanding of telco BSS systems including billing, order management, product catalog, CPQ and customer lifecycle management, with knowledge of how these capabilities support business operations

Platform Integration Architecture – Extensive experience designing API-first integration architectures, event-driven patterns and service abstraction layers that enable loose coupling in complex system landscapes, coding capability in at least one language, enabling credibility with engineering teams and hands-on spike work when needed

Vendor & Stakeholder Management – Strong ability to work with enterprise software vendors as strategic partners, negotiate technical implementations and manage complex stakeholder relationships across business and technology teams,ability to lead through influence rather than authority

Platform Engineering Mindset – Understanding of platform-as-a-product principles, developer experience design and how to build self-service capabilities that enable team autonomy at scale

Experience you’d be expected to have

Mandatory

Strong engineering background with hands-on experience in software development or systems engineering, demonstrating technical credibility through active contribution to architecture implementations, POCs and technical spikes

Extensive experience leading IT systems and BSS architecture in telecommunications or complex B2B environments, with demonstrated success modernizing legacy landscapes across multiple system domains
Experience building and leading architecture teams, with track record developing technical leadership capability and establishing architectural practices that scale across product engineering organizations

Proven track record defining and executing architectural strategies that enabled large-scale system rationalization, vendor consolidation and platform transformation while maintaining business continuity

Significant experience establishing API-first integration architectures in complex enterprise environments, including work with API management platforms, event streaming and microservices patterns

Nice to have

Strong background working with major enterprise platforms (Salesforce, ServiceNow, Microsoft) and telco-specific BSS vendors, including negotiating technical approaches and influencing vendor roadmaps

Demonstrated success working in product operating models and agile contexts, with understanding of how architecture enables rather than constrains product team autonomy and delivery velocity

Background in telco operations and BSS domains with deep understanding of the technical and organizational challenges in transforming mission-critical systems that directly impact revenue

Our leadership standards

Looking in:
Leading inclusively and Safely
I inspire and build trust through self-awareness, honesty and integrity.
Owning outcomes
I take the right decisions that benefit the broader organisation.

Looking out:
Delivering for the customer
I execute brilliantly on clear priorities that add value to our customers and the wider business.
Commercially savvy
I demonstrate strong commercial focus, bringing an external perspective to decision-making.

Looking to the future:
Growth mindset
I experiment and identify opportunities for growth for both myself and the organisation.
Building for the future
I build diverse future-ready teams where all individuals can be at their best.