What a fractional CTO is actually for

I’ve spent thirteen years working full-time. Every role I’ve had, I’ve been all in. I don’t naturally hire consultants, and I’m sceptical of anyone who shows up with a slide deck and leaves before the hard part starts.

So it’s worth explaining why I now work as a fractional CTO.

But first, a more useful question. If you’re a founder at seed or Series A and you don’t have a CTO yet, the question isn’t “should I hire a fractional one?” The question is: what’s actually happening to your technical decisions right now?

The four ways it usually goes

Nothing happens. No one is making deliberate technical decisions. Your infrastructure was set up by whoever was available at the time. Your architecture reflects the first thing that worked, not the best thing for what’s coming. Decisions get made by default, and defaults compound.

Your best engineer steps up. They’re talented. They care. But they’ve never hired a team, set an engineering culture, or made architecture decisions that need to hold up for three years. They’re learning on the job in a role no one formally gave them, without the authority to make the calls that need making. And they’re still expected to ship code.

You hire full-time. A good CTO costs $250K to $400K in total package. At seed stage, that’s a significant chunk of your runway committed to one person before you know whether the fit is right. The hire takes months. Onboarding takes months. If it doesn’t work, unwinding it is slow and expensive. Some companies at Series A can justify this. Most at seed can’t.

You bring someone in fractionally. One to three days a week. They make the architecture calls, set up the engineering practices, help you hire, and leave when the team can carry it. The tradeoff is real: they’re not there every day. They won’t carry the emotional weight of a co-founder. They will leave.

Most founders I talk to are living in option one or two and don’t realise it. They think they’re waiting until they can afford option three. What’s actually happening is that decisions are being made without them, by people who don’t have the experience to make them well, and the cost of undoing those decisions later is almost always higher than getting them right the first time.

What the role can do

A fractional CTO makes the calls that compound. Which tech stack to build on. How to structure the codebase so it doesn’t become unmaintainable in eighteen months. Whether to build or buy. Who to hire first, and what to look for. How to set up CI/CD, deployment, and monitoring so the team can ship with confidence rather than crossing their fingers.

Building the team is part of this. If you have no engineers and need to hire your first three, that’s CTO work: defining the roles, running the process, setting the bar, making the calls on who’s good enough. A fractional CTO who sets the architecture but can’t help you find the people to build it is doing half the job.

They set the engineering culture. Ownership, accountability, blameless post-mortems, code review standards. The things that determine whether a team gets better over time or slowly drowns in its own technical debt.

And right now, they should be making the AI decisions too. Not as a separate workstream. As part of every technical conversation. Where AI tooling creates real speed for the team. Where it creates risk. How to introduce it into workflows without shipping untested code to production. These aren’t AI questions. They’re engineering leadership questions that happen to involve AI.

What it can’t do

A fractional CTO is not a co-founder. They don’t lie awake thinking about your company. They care about the work, they’re accountable for outcomes, but the existential weight of the business stays with you.

They’re not there for every conversation. Things will happen on days they’re not in the room. The internal team has to be strong enough to handle the daily work. If they’re not, the first job is making them strong enough.

If what you need is twenty developers to execute a known spec, you need an agency, not a CTO. There’s a real difference between building a team and being a team. The CTO work is finding the right people, setting the standards, and making the architecture decisions. Actually supplying engineering capacity at scale is a different business.

And if something truly blows up, a crisis that demands full-time attention for weeks, the fractional model bends. Either the engagement temporarily scales up, or the founder carries it. That’s a real limitation. Pretending otherwise would be dishonest.

Why I’m doing it this way

I’ve been full-time at companies where I saw the cost of not having senior technical leadership early enough. Engineers making architecture decisions without the context to make them well. AI getting adopted without anyone thinking about what it means for the codebase. Platform decisions that cost six months to undo.

I could do that for one company at a time. But the pattern repeats everywhere. Founders at the same stage, facing the same gaps, making the same avoidable mistakes. I’d rather catch ten of those early than watch one go wrong slowly from the inside.

I’m also honest about where I’m most useful. I’m good at the technology, the engineering culture, and the AI integration. Product is where founders already have strong opinions. The gap is usually on the engineering leadership side, and that’s where I can do the most good in the least time.

And there’s a selfish reason too. A full-time CTO’s track record is tied to one company’s outcome. Most startups fail for reasons that have nothing to do with engineering. A portfolio means my work gets judged across multiple companies, which is a fairer reflection of whether I’m actually good at this.

Australia is behind on fractional technical leadership. Most of the advice available to local founders comes from people who’ve never built anything, or from overseas frameworks that don’t fit the local market. I’d rather be in the room.

When this doesn’t make sense

If you’re past Series A with 30+ engineers and a complex product, you need a full-time CTO. The decision surface is too large and too constant for someone who’s there two days a week.

If you have a technical co-founder who’s doing the job well, you don’t need me. You might want a sounding board or a mentor, but that’s a different engagement.

And if you’re looking for someone who’ll tell you everything is fine and validate decisions you’ve already made, we won’t be a good fit. The value of the role is in honest judgment, which sometimes means telling you the thing you don’t want to hear.

The honest framework

A fractional CTO makes sense when three things are true at the same time: you need senior technical judgment, you can’t justify or afford a full-time hire, and you have (or are building) an internal team that can execute between sessions.

That window is real. It doesn’t last forever. The point of the engagement is to close it: build the team, set the foundations, hire a full-time CTO if the company reaches the stage where that’s right, and move on.

If you’re in that window now and you know it, book a call. If you’re not sure, that’s also a good reason to have the conversation.