A social app for discovering events, booking tickets, and finding your crowd
CTO as a ServiceCustom Development
What is a fractional CTO?
A fractional CTO is an experienced chief technology officer who works with your company part-time, usually a day or two a week or a few days a month, instead of joining as a full-time employee. You get the same technical judgement, architecture decisions, hiring input and delivery oversight a full-time CTO would give you, at the level of commitment your stage actually needs.
The role goes by several names. Interim CTO, part-time CTO, outsourced CTO, virtual CTO and CTO as a service all describe roughly the same work. The differences are about duration and intent: an interim CTO usually covers a gap while you recruit, where a fractional CTO is an ongoing arrangement with no assumption that it gets replaced.
The job is not advisory. A fractional CTO who only has opinions is an expensive sounding board. The value is in owning the decisions and staying close enough to the work to know whether they were the right ones.
We do this for startups and scale-ups across the UK from our base in Bristol. Remote by default, on site when a week in the room is worth more than a week of calls.
- Technical strategy
- What to build, what to buy, and what the stack needs to cope with in two years rather than two sprints.
- Delivery oversight
- Sprint direction, code review, and unblocking the people doing the work, so progress does not stall waiting on a decision.
- Team and hiring
- Who you need next, how to assess them properly, and how to structure a team that can be handed work rather than managed line by line.
- Commercial translation
- Explaining the roadmap, the risks and the spend to a board or an investor in language they can act on.
The problem
Why things don't ship
You've got a clear vision, maybe even a dev team. But without senior technical leadership, progress slows, decisions get delayed, and the product never quite clicks the way it should.
Without someone technical to lead with confidence, everything starts to feel harder than it should.
No tech background
You know what to build and why. But turning that into architecture, hiring developers, and guiding a build? That's where it gets murky. Without someone technical to lead with confidence, everything starts to feel harder than it should.
Still waiting for the right CTO?
You might not need a full-time CTO. A part-time CTO can step in, make the right technical decisions, and keep things moving, without the cost, delay, or risk of a permanent hire.
Things are being built, but not led
Dev work is getting done. But without a clear roadmap, aligned priorities, or a technical point of view, it's all output with no real direction. Code piles up. Costs increase. And the foundation isn't strong enough to scale.
When a company needs a fractional CTO
Most companies come to us at one of six points. If more than one of these is true, the gap is leadership rather than effort, and adding another developer will not close it.
No technical co-founder
You know what the product should do and why. You do not have anyone who can tell you whether the plan, the quote, or the agency pitching you is sound.
Developers, but nobody leading them
Work is getting done and nothing is being decided. Priorities move every week, code piles up, and no one owns the architecture.
A CTO hire you are not ready to make
Hiring a good CTO takes months and a six-figure commitment. Until you know what the role needs to be, a fractional CTO keeps the build moving and helps you assess candidates when the time comes.
A raise where the tech story has holes
Investors will ask about the stack, the roadmap, the risks and the team plan. Those answers need to be true as well as confident, and documented well enough to survive diligence.
A codebase nobody understands
The original developers have gone, changes take longer every month, and nobody can say with confidence what breaks if you touch it. That needs assessing before it needs rebuilding.
Growth the architecture cannot take
What worked at a hundred users is creaking at ten thousand. Someone has to decide what to fix now, what to live with, and what to design differently.
What we do as your fractional CTO
The work is the same work a full-time CTO does: architecture, priorities, hiring, delivery. What changes is the commitment. We plug in quickly, make informed technical decisions, and lead with calm, experienced direction without slowing things down.
From product vision to technical execution
We turn your product goals into clear technical decisions, from architecture and hiring to tech stack choice and delivery plans.
Hands-on, not hands-off
We don't sit back and advise. We get involved in leading sprints, reviewing code, unblocking teams, and keeping momentum steady.
Flexible support, real impact
Whether you need a few hours a week or a few days a month, we slot in where we're needed most, without adding a permanent line to your payroll.
Investor-ready clarity
We help you speak tech with confidence, through clean documentation, smart roadmaps, and a clear story about where your product is going, and how it gets there.
How a fractional CTO engagement works
Fractional work is priced by commitment rather than by deliverable, so the shape of the engagement matters more than the headline rate. Three shapes cover almost everything.
- Monthly retainer, fixed days
- The most common arrangement. You buy a set number of days a month, typically between two and six, spread across the month so the team is never waiting a fortnight for an answer. Easy to budget, and easy to scale up through a push.
- A fixed day each week
- A standing day or half-day, plus availability in between for the questions that cannot wait until next Tuesday. Suits teams in active delivery, where decisions come up constantly.
- A defined piece of work
- Technical due diligence, an architecture review, running a hiring process, or taking over a build that has gone wrong. Scoped and priced as a project, with a clear end.
What moves the cost
Three things. How many days a month you need. How senior the work is, because board-level strategy and hands-on code review are not the same job. And whether you need someone reachable between sessions, which is usually the difference between a team that keeps moving and one that queues up questions.
A fractional CTO costs a fraction of the full-time equivalent because you are paying for the decisions rather than the desk. Expect a monthly retainer rather than an hourly rate, reviewed as your needs change. We quote after the intro call, once we know what the build actually needs. If a few hours a month is genuinely enough, we will say so.
How it compares to a full-time CTO or an agency
All three are the right answer somewhere. The question is which problem you have: missing judgement, missing capacity, or missing both.
| Comparison | Fractional CTO | Full-time CTO | Development agency |
|---|---|---|---|
| What you pay for | A set number of days a month. | A salary, equity, and the on-costs of a senior hire. | Delivery hours, usually billed by the team. |
| Time to start | Weeks. | Three to six months to hire well. | Weeks, once the scope is agreed. |
| Where the decisions sit | With you, advised and owned by someone senior. | In-house, every day. | Inside the agreed scope, and nowhere above it. |
| Best when | You need senior decisions more than another pair of hands. | Engineering is the core of the business and the team needs a leader in the room daily. | The plan is already clear and you need it built. |
| Weak spot | Not there every day, so the team has to be able to act between sessions. | Expensive and slow to reverse if the fit is wrong. | Nobody is accountable for the decisions above the contract. |
Recent work
All-in-one SaaS platform for measuring and managing social sustainability
CTO as a ServiceAI DevelopmentCustom Development
What we deliver
A clear technical roadmap
We turn your product goals into a smart, actionable plan, with the right stack, scope, and priorities from day one.
Oversight your team can trust
From reviewing code to unblocking sprints, we provide the senior guidance your developers need to move fast without breaking things.
Confidence in every decision
Whether you're in front of investors or hiring your first engineer, we help you move with clarity and avoid costly mistakes.
What clients say about Celestify
Celestify improved our website performance and streamlined the backend, enabling our team to build faster, better customer experiences resulting in higher conversion and more pipeline.
Evan Benet
SVP of Growth, Perry Weather
We have been working with Paras and his team at Celestify for almost 3 years and we are extremely pleased overall with his services. He is smart, plans well, thinks of solutions ahead, carries through full implementation, and is there to support after deployment.
Miriam Boudreaux
CEO, Mireaux Management Solutions
Working with Celestify has been a truly smooth and seamless experience. What stands out most is their unwavering commitment to finding solutions, no matter how complex the challenge, they approach every task with a can-do mindset and deliver results.
Drishdey Caullychurn
Founder & CEO, TEXpert AI
Working with Celestify doesn't feel like working with an external team. That's the best way to explain how simple and enjoyable it is to work together.
Ishaaq Shafi
CEO & Founder, Chat University
Paras and his team are absolutely incredible. Super professional, very knowledgeable and product centric. He guided our team of developers and delivered a world class product within a very short timeline.
Agnieszka Dulas
Co-founder, Fritty Club
Working with Celestify was an absolute pleasure! They helped us bring our brand-new website to life on a different backend, and the results have been incredible.
Rini Kamal
Director, Communications, Catalyst Exchange
