Everyone talks about software modernisation—but what does it really mean? Is it about rewriting legacy systems? Refactoring bit by bit? Moving to the cloud? Killing the monolith? Or just keeping things running while everything around you changes? And what's the right time to modernise—when tech becomes a bottleneck, when a new CTO joins, when a funding round lands, or when your best engineers threaten to quit? What about the trade-offs? How do you make a business case for something that has no clear ROI? How do you modernise while still delivering new features? What happens when the team that built it has left—or worse, when they haven't? Is modernisation even the right word, or is it just... maintenance we've renamed to make it sound exciting? This is a session for senior engineering leaders and CTOs to dig into what modernisation actually looks like—messy trade-offs, half-finished migrations, org challenges, architectural dead-ends, and the rare clean break. We're running this as an unconference—there's no fixed agenda, no keynote, and no panels. Instead, we'll kick off by gathering topics from everyone in the room, then shape the sessions around what people actually want to talk about. You can suggest a topic, lead a conversation, or just join the ones that interest you most. It's informal, interactive, and driven by the collective experience in the room. Expect stories, questions, patterns, hard-won lessons—and a few things people don't usually admit to in more polished settings. This event is organised by RecWorks on behalf of the London CTOs. We would like to thank our sponsors carwow and Codurance. About Codurance: Codurance is a global software consultancy that helps businesses build a better, sustainable technical capability that supports growth and innovation. With offices in the UK, Spain, Portugal, USA and Brazil we provide services across software delivery, strategic advice, cloud platforms and learning & development. Find out more at https://www.codurance.com/ About carwow: carwow is one of Europe’s leading car-changing platforms, helping over 12 million people buy and sell cars online. In 2024, they formed the Carwow Group with the acquisition of Autovia, bringing together a portfolio of top automotive brands, including one of the world’s most-viewed motoring YouTube channels. Find out more at https://www.carwow.co.uk About Recworks: RecWorks are the creators of many groups and communities including Meet-a-Mentor a free slack group that introduces aspiring CTOs to experienced CTOs, as well as more junior developers - 3000 introductions made and counting! They also founded one of the largest Java User Groups in Europe - the 8000+ strong London Java Community. They are a community-driven recruitment agency focussing on tech placements in London. London CTOs are a 10-year old London based CTO community with over 1200 members.