Hey, I'm Lewis

I'm a Staff-level Software Engineer based in London with experience across big tech and early-stage startups. I care about using my career to make a difference and I’m passionate about building great products that solve meaningful problems.

Most recently, I was a Founding Engineer and Tech Lead at ClimateAligned, a pre-seed climate finance AI startup, where I built products and platforms using LLMs, agents, RAG, and complex data workflows. Before that, I worked at Microsoft and Metaswitch, leading engineering teams and delivering complex systems at scale.

I'm now looking to apply this blend of engineering depth, startup execution speed, and applied AI expertise to impactful work where advanced AI can deliver real value.

My focus is on Product Engineering and applied AI, with a strong interest in leading teams, mentoring others, and turning complex problems into shipped products.

ClimateAligned, 2023–2025

I joined as a founding engineer at ClimateAligned, a pre-seed AI startup focused on sustainable finance. Over time I stepped into the Tech Lead role, guiding senior engineers and setting technical direction across frontend, backend, and AI systems. I:

• Built a bond data platform using complex LLM workflows to extract structured, high-quality data for a market-level web app.
• Designed an internal DAG-based workflow builder enabling scalable custom data delivery projects for multinational financial institutions.
• Developed an agentic dashboard builder automating repeatable analysis tasks into user-facing dashboards. I delivered at pace through multiple pivots, maintaining engineering quality and ensuring the team kept aligned with the fast-moving AI landscape.

Microsoft, 2021–2023

I worked as a Senior Software Engineer at Microsoft in the Teams organisation, where I:

• Led a 10-person engineering team, delivering projects on time and to a high standard.
• Delivered large cross-team projects, collaborating across product and engineering groups.
• Contributed to architecture, technical writing, and project management alongside coding.
• Championed accessibility, embedding it across processes and product design.
• Mentored engineers through one-to-one conversations, talks, and written guidance.

Metaswitch, 2018–2021

At Metaswitch (later acquired by Microsoft), I worked as a Senior Android Engineer on a complex VoIP communications app. I delivered projects including:

• Migrating the app to Kotlin
• Achieving Accessibility compliance
• Replacing the legacy HTTP stack
• Integrating advanced VoIP features with native phone systems I also helped scale the team from 3 to 10 engineers and mentored colleagues at different levels.

I decided in 2022 that I needed to make a change to work on solving some of the big problems in the world. As a start, I chose to start a part-time Masters degree in Climate Change Policy at King's College London. I am in the final year this programme. My interests lie at the intersection of policy, finance, and technology, as I believe this is where the most signficant impact can be made.

I am also dedicating a lot of my spare time to understanding the development and capabilities of AI as it rapidly transforms our world. I built products with the GPT-4 APIs as soon as they became available and have recently been exploring the potential of local LLMs.

If you've got any interesting opportunities or simply wish to discuss anything on this website then drop me a note.

Contact me on LinkedIn or via email at lewis [at] lewisdeane [dot] com.