Learn how a top AI/ML software engineer thinks about MVPs from his own experience as an inventor, founder, advisor, and investor to startups.
Stef Lewandowski
London, UK
Fractional CTO / tech lead working on applied AI
I’m an experienced early-stage startup tech/product lead with a mix of overlapping skills in software development, design, and business model innovation.
Throughout my career, I’ve sought to find repeatable ways to discover new opportunities, prototype and develop early-stage tech startups and scale them to have an impact on solving problems the world faces.
Work
Translucent - The CFO super-app for multi-entity finance teams
https://translucent.ioTranslucent is the CFO super-app that solves the everyday problems of finance teams. Connect to your existing accounting solutions to create a single system of record.
Led the development of the first prototype, wrote the first lines of code, hired the early team, enabled the company to raise $9m seed, got to first revenue, handed over to ongoing leadership.
Experience
Pre-launch conversational AI startup
Fractional Applied AI CTO / Lead Engineer
Jan 2025 - Apr 2025
Fractional advisory for a pre-launch early stage conversational AI startup - featuring real-time transcription, live response generation by an assistant during conversation.
Aila - Oak National Academy
Fractional Applied AI Engineer
Jan 2024 - Apr 2025
Helped develop one of the first publicly released generative AI tools via the UK government. An AI assistant to help teachers develop resources to use in their lessons, based on an open API and database of content developed by Oak National Academy.
On Deck
Director of Platform
Mar 2021 - Sep 2022
Where top tech talent goes to explore what’s next.
Oak National Academy
Head of Engineering
Mar 2020 - Mar 2021
When COVID hit, I helped build a platform to support 4.5M children per month to continue learning online.
ING Bank
Venture Builder
Aug 2018 - Apr 2020
A pioneer in digital banking for retail and wholesale clients, driving innovation and sustainability initiatives.
Rainmaking
Venture Builder
Sep 2016 - Aug 2018
We unleash the power of entrepreneurship to solve big problems with the world’s leading companies.
Makeshift.io
Founder and Chief Technology Officer
Jan 2013 - Jan 2015
Startup studio building and testing digital products on repeat
Aframe
Technical Co-founder
Mar 2009 - Mar 2012
Co-founded a media collaboration platform startup which raised over $15m of investment.
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