by Gary Worthington, More Than Monkeys

The title “Fractional CTO” gets thrown around a lot, and often confused with “Interim CTO.” They sound similar, but they are very different roles.

An Interim CTO usually steps into a business full time for a fixed period, often to cover a leadership gap or drive through a transformation. They are embedded, they own the entire technology function, and they live in the company’s world until a permanent hire is found.

A Fractional CTO provides part time leadership across multiple companies, often startups or scaleups. Instead of being full time in one business, you drop in with high impact guidance, technical direction, and hands on support. You are there to give clarity and confidence without the overhead of a permanent hire.

Both roles demand technical authority and leadership, but fractional work is a unique blend. You are not just a contractor or advisor, you are a partner who can flex between coding, strategy, investor conversations, and team leadership.

Some treat it as a glorified contractor, someone who sets up a few AWS accounts, hires a developer, and checks in occasionally. Others think of it as an advisor, someone who reviews decks, joins investor calls, and gives “technical input.”

The reality is that a true fractional CTO is both of those things, and a lot more. It is a role that requires deep technical authority, consultancy skill, and the ability to pitch the same message to entirely different audiences.

Over the last two decades, I have stepped into dozens of companies as a fractional CTO, ranging from pre seed startups with a prototype held together by duct tape, to post Series A businesses that need to scale fast without blowing their burn rate. What I have learnt is this: the role is not about being a part time engineer or a part time consultant. It is about being a full time leader in part time hours.

Here are the traits and skills that matter most.

1. Technical Authority That Cannot Be Faked

Startups do not need theory. They need certainty.

When a founder asks, “Can this scale?” they do not want a vague answer, they want confidence backed by experience. They want to know if the backend can handle a spike in traffic, if the delivery pipeline is robust enough to ship daily, and if the architecture will survive scrutiny when investors bring in their own technical due diligence.

This is where technical depth matters. A fractional CTO has to bring scars from real projects, having personally built and run systems that worked at scale. You cannot outsource credibility.

I have been in situations where the quickest path was rolling up my sleeves and writing the backend myself. Other times, the job was simplifying an over engineered mess into something lean and maintainable. Either way, when I say, “This will work,” it is because I have lived through the alternatives.

And that credibility is what wins trust.

2. Consultancy Skills That Unlock Business Value

Here is the nuance: raw technical strength is not enough.

A startup does not just need working code, they need working strategy. They need someone who can look at the bigger picture and answer:

• What is the cheapest way to validate this idea?
• Which technical risks are real, and which are noise?
• How do we build an MVP that gives confidence without wasting six months?

That is consultancy. It is about asking better questions than the founder thought to ask. It is also about showing them what not to build, where they can cut corners safely, and where cutting corners would destroy trust with users or investors.

Sometimes my job is literally to stop a team from wasting half their seed round building features nobody needs. That is not “being negative.” That is creating business value.

3. Adaptive Communication Across Audiences

The hardest skill, and the one most overlooked, is communication.

A fractional CTO is constantly moving between worlds:

Investors, who want to know the platform will not collapse the moment it grows, that the IP is defensible, and that the tech strategy is aligned with the growth plan.

Founders, who need plain answers about cost, timelines, feasibility, and risks. No jargon, no fluff, just clarity.

Engineering teams, who need detailed direction, architectural clarity, and standards that will not change with the wind.

The art is in shifting pitch and language without shifting substance.

A Real Investor Call on AWS Architecture

In one Series A round, the lead investor was nervous about scaling. The product was built on AWS API Gateway and DynamoDB, and their worry was that the architecture would not stand up to rapid growth.

For the engineers, the story was clear: we had split synchronous API calls from asynchronous workloads, DynamoDB was provisioned with on demand scaling, and read and write patterns had been tested under artificial load using Locust. CloudWatch metrics and alarms fed into dashboards in Grafana, and traces in X Ray gave us end to end visibility. We knew exactly where the limits were and had the alerts wired in long before customers would ever notice.

But that level of detail would have been meaningless to investors. So I translated:

“We have deliberately designed the system so customer requests never negatively impact on the database. The API scales instantly as traffic grows, and the database automatically expands capacity with no downtime. Just as important, we have real time observability in place. That means we do not just hope it will scale, we can see it happening, we know where the thresholds are, and we get alerted before there is ever a customer impact. We have tested this at traffic levels 10x above today’s usage, and will continue to do so. The result is predictable costs and predictable performance, which means the business can grow without worrying that the tech will break or the AWS bill will spiral.”

That explanation got nods around the table. The investors understood that scaling risk was managed and that costs were under control, and that the business had the visibility to stay ahead of problems. The engineers, meanwhile, knew we had the dashboards, alerts, and traces to prove it.

That is the job: same truth, different pitch.

A Founder Conversation on Observability

Founders, however, often need the same story told in a different way.

I have sat in meetings where a founder has questioned why we were spending £100 per month on observability tools. To an engineer, the answer is obvious: logs, metrics, and traces give us confidence that the system is behaving as designed. But to a founder, £100 looks like another line item on an already stretched budget.

So I explained it like this:

“Think of this spend as insurance. Without observability, the first time we know about a problem is when customers complain or churn. With it, we get alerted before users ever notice. Spending £100 a month to avoid a potential £1,000 loss in downtime or failed transactions is not a cost, it is protection. It is how we stop a bad day turning into a funding risk.”

The founder understood that observability was not about graphs and dashboards, it was about protecting revenue, reputation, and investor confidence.

Again, same truth, different pitch.

4. Leadership in Chaos

Let us be honest: most early stage startups are chaotic. Priorities change weekly. Funding rounds slip. Competitors launch suddenly. Engineers leave mid project.

A fractional CTO does not get to demand calm, they have to create it.

That means keeping engineering focused on what matters, helping founders navigate uncertainty, and giving investors confidence that there is a technical plan underpinning the chaos. It is about leading through ambiguity, not waiting for perfect conditions that will never come.

This is where observability plays a second role. You cannot stop the storm, but you can give the business radar. Real time insight into system health, error rates, and usage patterns turns chaos into manageable signals. Instead of arguing about whether the platform “feels” slow, you show response times over the last 24 hours. Instead of debating whether the database is a risk, you show the current utilisation and the auto scaling policy that keeps it safe.

Leadership is not about eliminating uncertainty. It is about making it visible, measurable, and actionable, so that chaos does not become paralysis.

My job is to give the business stability when everything else is moving quickly. Observability, with metrics, tracing and logging done properly, is one of the fundamentals that makes that possible.

5. The Real Lesson: Selling Certainty

When you strip it all back, being a fractional CTO is not about selling hours. It is not even about selling technical skill.

It is about selling certainty. Certainty that the tech will work when it matters. Certainty that the strategy aligns with the business plan. Certainty that when investors ask the hard questions, the answers will land.

That is why the best fractional CTOs are more than engineers, more than consultants, and more than communicators. They are the rare blend of all three.

And that is what I bring when I step into a company: not just code, not just advice, but the confidence that the business can move forward with clarity.

Gary Worthington is a software engineer, delivery consultant, and agile coach 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.