Stelios Psarras · Principal Architect & Technical Lead

Engineering clarity where complexity matters.

Independent since 2002: my consultancy designs, builds and rescues critical systems. Today that mostly means data and AI platforms on AWS.

Principal architect, technical lead, start-up CTO and AWS and cloud subject-matter expert, for the BBC, AstraZeneca, Centrica, The Economist and the UK government.

Get in touch What I do

Organisations I've worked with

Private sector

Public sector

Department for Work and Pensions
Department of Health
Ministry of Defence
NHS Professionals
UK Border Agency
UK Home Office

Expertise

What I'm brought in to do.

Foundations

Cloud & Platform Engineering

Reliable foundations for systems that matter.

AWS platforms, infrastructure as code, and recovery you've actually tested.

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Architecture & Systems Design

Designing for change, not for diagrams.

Systems people can understand, change and keep running.

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Intelligence & Delivery

Data, Search & Applied AI

Data and search that hold up in production.

Pipelines, search and AI applied to real systems, not demos.

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Delivery, Rescue & Modernisation

For when it has to ship.

Stabilising, rescuing and modernising systems against real deadlines.

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Leverage

Technical Leadership & Enablement

Leadership rooted in engineering reality.

Technical direction from someone who still reads the code.

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Selected work

Problems I've been trusted with.

Pharmaceuticals · 2021–2022, 2025–2026

Designed in 2021, asked back in 2025: a Data & AI platform that lasted

A global pharmaceutical company

I was technical lead for a multi-tenant AWS Data & AI platform: about 25 products, each bootstrapped in under a day, and the full RAG data path. The client built on my 2021 design, then asked me back.

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Energy · 2022–2024

Recovery built to survive a ransomware attack

A major UK energy provider

I led the design and build of an immutable backup platform across AWS, GCP and Azure, so a major UK energy provider could keep operating if it were ever hit by ransomware.

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Media & Publishing · 2017–2018

Making the board case for an AI venture

A global media and publishing company

As designated CTO of a planned AI and data science spin-off, I built the case to the board with the Chief Digital Officer, CTO and Finance Director, and designed the data platform behind it.

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Have a hard problem worth solving?

Tell me about the system, the team or the deadline. I'll tell you honestly whether I can help.

Get in touch See my work