First CTO

Fractional CTO service for seed and early stage founders

Get expert technical leadership without the full-time commitment. Navigate technology decisions, build your engineering team, and scale your product with confidence.

About Me

Hi there!

Over the past thirty years I've worked across almost every layer of the technology stack and, more importantly, across every stage of a company's life. From early-career engineering through senior technical leadership, I've seen first-hand how the right technical decisions at the right time can make or break a growing business. For fourteen of those years, to 2025, I served as CTO of a startup, helping to shape its technical direction from a small, scrappy team through to a company of around one hundred people and leading to a successful acquisition in 2025.

That journey taught me things that only come from living through it. I've navigated the messy reality of scaling systems and teams at the same time — making pragmatic architecture choices when budgets were tight, hiring and mentoring engineers, and learning when to build, when to buy, and when to leave well alone. I've made plenty of mistakes along the way, and honestly, those have been some of the most useful lessons of all.

As a fractional CTO, my aim is to give startups and early-stage companies access to that kind of hard-won experience without the commitment of a full-time hire. Whether you need help setting a technical strategy, making sense of your architecture, building out your first engineering team, or simply want a seasoned sounding board before making a big call, I'm here to give you straight-talking, practical advice — no jargon, no ceremony, just honest guidance that helps you move forward.

Cheers for now,
Tony

Profile pic

Tony Johnson
Founder, FirstCTO

Accidental CTO Book

Many technical founders don't set out with the goal of being a CTO — they just want to build something cool and interesting. But the startup grows, the team grows, and before long you're responsible for far more than just the technology. "The Accidental CTO" is the book I wish I'd had when I first found myself leading a growing company with no roadmap for everything that comes after the code.

It covers the stuff that nobody warns you about: what's product-market fit, why does the board keep talking about ARR, net revenue retention, how customer demands and acquisition cost shapes your roadmap, and how you and your engineering team needs to understand and work hand in hand with sales, marketing, support, HR, and operations.

From navigating board meetings to figuring out why your roadmap never survives first contact with a sales pipeline, right through to surviving the minefield of due diligence when acquisition comes knocking — and having the honesty to recognise when the company you built needs a different kind of leadership to reach the next level. That takes a different set of skills, and (spoiler) knowing yourself well enough to hand over with confidence is one of the most important lessons in the book.

Coming 2026 in hardback, paperback and on Amazon kindle. If you want updates on how the book is progressing or to be notified when it's available, Sign up for our newsletter.

The Accidental CTO book cover

"The Accidental CTO"
Coming soon

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