by Gary Worthington, More Than Monkeys

Founders often ask the same question once they’ve got a product in market and a bit of traction: when should we bring in a CTO? The timing isn’t obvious. If you hire too soon you risk adding overhead before you’ve really nailed product–market fit, and the cost of a senior executive can be difficult to justify when you’re still iterating on the basics. If you leave it too late you run into scaling problems, mounting technical debt, and a credibility gap with investors who expect to see a technical leader sitting next to you.

Increasingly, startups are bridging that gap by working with Fractional CTOs — senior leaders who work with you part-time to give you the strategic input you need, without the full-time salary you don’t yet require. It’s a pragmatic solution, but it only works if you understand what a CTO is really there to do.

What a CTO Actually Does in a Startup

One of the most common mistakes founders make is assuming that the best developer automatically becomes the CTO. A good developer and a good CTO are very different things. A CTO is not just writing code. They are shaping technical strategy, defining architecture, building the engineering team, and making sure the technology roadmap aligns with business goals.

Yes, in a five-person startup the CTO will still be hands-on, but the value they bring is in steering decisions that have long-term consequences. For example, when you’re deciding whether to build a data pipeline in-house or to rely on a managed service, the CTO isn’t just looking at the technical pros and cons — they’re also weighing the impact on hiring, costs, speed to market, and investor perception. That combination of technical depth and commercial awareness is what makes the role unique.

Signs You Don’t Need a Full-Time CTO Yet

There are plenty of early-stage companies who rush to hire a CTO when they don’t really need one. If you’re still validating whether your idea even has traction, and the engineering challenges are straightforward, a strong senior engineer with occasional outside guidance may be enough.

At this stage investors care far more about usage, growth, and retention than whether your architecture is cloud-native and multi-region. For example, a consumer app that is essentially CRUD on a database does not need an expensive CTO to run it in the early months. If your team is small and your infrastructure is relatively simple, you’re usually better off keeping costs low and focusing on proving the business.

Signs It’s Time to Hire a CTO

The point where a CTO becomes unavoidable usually comes when scale and complexity collide. If you have more than ten developers and no technical leader, coordination breaks down quickly. If your product relies on complex infrastructure — payments, machine learning, compliance-heavy systems — you can’t afford to get those wrong. And when you reach Series A or B, investors will expect to see a credible technical leader at the table.

I’ve seen this with B2B SaaS products that handle financial transactions. As long as they were serving a handful of pilot customers, a strong engineering lead could cope. But the moment they had to process thousands of payments reliably and prove compliance to enterprise customers, it became clear that a CTO was needed to provide direction and reassure investors.

The Case for a Fractional CTO

This is where the Fractional CTO model makes sense. It gives you access to senior experience without the cost of a full-time executive. For many startups, the gap between “two developers shipping fast” and “a 20-person engineering team with serious investor oversight” is several years wide. A Fractional CTO can bridge that period.

In practice, this means someone spending a day or two a week with you, setting technical direction, mentoring your in-house engineers, helping you with hiring, and establishing processes that will scale. I’ve worked with marketplaces where the Fractional CTO set the initial cloud architecture, built the hiring plan for the next twelve months, and then gradually stepped back as a permanent CTO came in post-Series A. The founder got the benefit of senior input without carrying the full cost too early.

Making the Transition

If you do go down the Fractional CTO route, you need to be clear about what happens next. The role works best when it’s seen as laying the foundations: setting architecture, cloud strategy, and engineering practices that make scaling less painful. At some point the business will outgrow part-time leadership, either because the team is too big, the technical demands too complex, or because investors insist on a permanent leader.

Handled properly, the transition is smooth. A good Fractional CTO will often help you hire their permanent replacement and ensure continuity. That way you don’t lose momentum, and the permanent CTO inherits a solid base rather than a mess.

Closing

Hiring your first CTO is a pivotal decision, but it only makes sense when the timing is right. Before then, a Fractional CTO can give you experience, credibility, and strategic direction at a fraction of the cost. The real mistake isn’t choosing one path over the other — it’s failing to make a conscious decision and drifting into a situation where you either overspend on leadership too early, or under-invest and watch technical problems pile up until they threaten the business.

Gary Worthington is a software engineer, delivery consultant, and Fractional CTO who helps teams move fast, learn faster, and scale when it matters. He writes about modern engineering, product thinking, and helping teams ship things that matter.

Through his consultancy, More Than Monkeys, Gary helps startups and scaleups improve how they build software — from tech strategy and agile delivery to product validation and team development.

Visit morethanmonkeys.co.uk to learn how we can help you build better, faster.

Follow Gary on LinkedIn for practical insights into engineering leadership, agile delivery, and team performance.