Fractional & Interim CTO · Product Owner · Full-stack Developer
Fractional CTO and product ownership, pay as you go, no payroll
Roadmap, architecture and code from one person. You book days, not usage: a fixed number per month, or one defined project. Change them as the product changes.
For founders and product teams in Europe and the UK.
- Ownership from week one
- No recruiting
- Days, not salary
The problem
Product decisions and implementation are two jobs.
Most companies need both long before they can afford to hire either. You have a live product, paying customers, and nobody senior owning the technical side.
Where it breaks
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Nobody owns the technical side
You know what the product should become. But nobody decides what gets built, what doesn't, and how long the architecture has to last. So you approve estimates you can't check, and take the answer on trust.
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Cheap today, expensive later
The wrong database, the wrong platform, the wrong integration. Each costs a few days now. Each costs months once customers depend on it. The same goes for the questions you can't answer yet. How does the architecture scale? Where do the risks sit? What happens when your lead developer leaves? Investors ask those first.
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Advice that stops at the recommendation
Consultants hand over a document and leave. The decision, the code and the responsibility then sit with three different people. Nobody owns the result.
My approach
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One person decides and builds
As your fractional CTO, I make the technical decisions. Then I write the code that follows from them. Decision, implementation and accountability stay in one pair of hands. And that person is in the room when investors, boards and customers ask the technical questions.
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A scoped start, then a steady pace
We start with a 15-minute call. If it fits, a Statement of Work sets scope, cadence and terms upfront. After that you book days, not a salary. Choose a standing monthly engagement, fixed days per week, or one defined project.
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No permanent hire, no lock-in
Senior ownership from the first week. Scale it up or down as the product changes. No recruiting, no payroll. You own the code, the infrastructure and the documented architecture decisions from day one. When you hire a permanent CTO, the written handover is already part of the engagement.
Services
Take one, or all four.
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Fractional CTO / Interim CTO
Technical leadership on the days you book. For a product already in the market, with nobody senior owning the technical side. You get architecture and technology choices, build-vs-buy calls, hiring and engineering process. Security, data protection and infrastructure cost are part of the job. So is the technical case you put in front of investors.
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Fractional Product Ownership
A dedicated product owner inside your team. For teams that build faster than they can decide what to build. You get roadmap, discovery, prioritisation and stakeholder alignment. I run the backlog and the sprints for the length of the engagement. One owner from discovery to release.
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Full-stack Delivery
Implementation across the stack, by the person who made the call. For teams that need capacity, and founders with no team yet. My stack is ASP.NET Core and C#, React and TypeScript, native iOS in Swift, with PostgreSQL, SQL Server or MongoDB behind them. Node.js and Python when that is what your team runs.
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Cloud Architecture & Delivery
Infrastructure your team can release on without an ops hire. For products outgrowing the setup they started with. Cloud architecture on Azure, with Cloudflare at the edge for DNS, CDN and Workers. Containerised builds, CI/CD pipelines. I set up the environments. Releases get safer, and you can see what the infrastructure costs and why.
The information on this website describes my services. It is not a binding offer. Scope, dates, rates and terms apply only as set out in the signed Statement of Work.
How it works
We agree every term before the first line of code.
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Discovery call, 15 minutes
Fifteen minutes on your product, your team and the current bottleneck. No pitch, no obligation. By the end we both know whether to take it further.
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Scoped engagement, signed upfront
A Statement of Work sets scope, cadence and terms, in English or German. Nothing starts before it is signed.
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Embedded delivery, week by week
I work in your project board, your repository and your standups. Regular syncs, an agreed scope for each period, and scope that changes when the product does.
About
I've been on the hook for the estimate and the invoice since university.
I am Jonathan Philipps, M.Sc. Computer Science. I grew up in Germany and studied there. I have built software since 2012, as a full-stack engineer and architect. My first clients came while I was still at university. The deadline and the invoice were mine from the start, not just the code. What still interests me is the problem itself: taking a half-defined idea, working out the version that can be built, and getting it in front of real users.
I work embedded in your team or on my own. I own the technical decisions and the implementation that follows from them. If you have an engineering team, I lead it in your process, your repository and your standups. If you don't, I build it myself. Either way, your team should know more at the end than at the start. If an idea won't hold up in production, you hear it in the first week, not in the retrospective.
I stand behind everything that ships, line by line. I write decisions down and document the architecture while it is built, so nothing critical depends on me being in the room. I commit to dates I can hold, and if anything puts one at risk you hear it early, not on the deadline. A good engagement ends with a quiet release, and a team that isn't nervous about the next one.
In 2026 I moved to Malta, where Nephelix Nova Ltd. is incorporated. I live and work here, in an EU jurisdiction and in European working hours. The address changed; the person doing the work did not. You work with me, and I do not subcontract. Contracts, documentation and daily work run in English or German, whichever your team uses. I leave legal and tax advice to the people who do it every day. Invoices carry the Maltese VAT ID MT32627918. For business clients in the EU with a valid VAT ID the reverse-charge procedure applies. For clients in the UK the supply falls outside EU VAT and the client accounts for it under UK rules. Contracts run under German or Maltese law, by agreement.
- Entity
- Nephelix Nova Ltd.
- Jurisdiction
- Malta, EU
- Engagements
- Fractional, embedded or project-based
- Governing law
- German or Maltese, by agreement
- Markets
- Europe and the UK
- Languages
- German (native) & English
Questions
What you should know before we talk.
Who does the work?
I do. All of it.
Nephelix Nova Ltd. is a one-person firm. The person who runs the discovery call writes the code and joins your standups.
That is deliberate. Product decisions and implementation stay in the same hands, with no handover between them.
Do you use AI to write the code?
As a tool, the way I use CI and code review.
It keeps routine work off the critical path: boilerplate, migrations, first drafts of tests. That leaves more time for the decisions that are expensive to get wrong.
It changes nothing about what you get billed for or who is accountable. I read, test and stand behind every line that ships, and you pay for the booked day, not for keystrokes. Where a tool cannot be used on your code — client policy, licence terms, confidentiality — I work without it.
What happens if you're ill or unavailable?
Delivery pauses. There is nobody else to hand it to.
That is the trade-off of hiring one person instead of an agency, and you should hear it here rather than find out mid-sprint: an absence moves the dates by its own length.
What does not pause is your access to the work. Code, infrastructure and accounts are yours from day one, and I write architecture decisions, runbooks and the backlog as the work happens — so another developer can pick it up without me.
Planned absences we agree in advance. The Statement of Work sets the notice period, what happens to work in progress, and the written handover: architecture, open decisions and next steps.
What does a fractional engagement involve?
Product ownership and engineering from one person, at an agreed cadence.
I work embedded in your team instead of filling a permanent position at that level. We agree scope, cadence and terms before the work begins.
You book days, not a salary: a standing monthly engagement, fixed days per week, or one defined project.
A booked day buys senior time and decisions, not a fixed result. When you want a fixed result for a fixed price, we define it as a separate project with its own acceptance criteria.
What does it cost?
It depends on scope and cadence, and you get the figure before anything starts.
Three things move the number: how many days a month you book, how long the engagement runs, and whether it covers product ownership, engineering, or both.
The Statement of Work names the rate, the cadence and the invoicing terms before the first line of code. Travel is billed at cost and agreed in advance; nothing else is added later.
When can you start?
Ask in the call and you get a date, not a maybe.
I run a limited number of engagements at a time, so the honest answer depends on what is already booked. A defined piece of work can usually start sooner than a standing monthly engagement.
Whatever we agree, the Statement of Work is signed before the start date — and the start date is in it.
What if I already have a CTO or a lead developer?
Then I work under them, not around them.
Not every engagement needs someone at the top. I add senior capacity to a team that already has direction. I can take one defined area off their hands, or give a second opinion on a single decision: architecture, build-vs-buy, a stack choice.
We agree who decides what before the work begins. Nobody has to guess who owns which call.
Can you build the product if I don't have a team yet?
Yes.
With no team in place, I take the build end to end: architecture, implementation, infrastructure and releases. The engagement model stays the same.
Can you take over an existing codebase?
Yes.
Inherited code, thin documentation and a developer who has already left are a normal starting point. I begin with a review of the code, the infrastructure and the release process.
Then you get three answers: what is worth keeping, what carries risk, and what a change would cost. A rewrite is a decision we take together, on evidence, not a default.
Can I engage you for development only?
Yes.
You can book any of the four services on its own or in combination. Engineering capacity without the product ownership is a common arrangement: extra capacity for a few weeks, or a longer-term addition to your team.
How does an engagement begin?
A 15-minute call, no obligation.
That is enough for me to understand your product, your team and the current bottleneck. If it fits, the Statement of Work follows before any work starts.
How do I end the engagement early?
In writing, within the notice period in the Statement of Work.
The notice period and any minimum term are agreed before you sign, not buried in terms you read afterwards. A standing engagement can be scaled down instead of ended, if that fits better.
You get the same handover you would get at a planned end: architecture, open decisions and next steps. Everything else already sits in your repository and your accounts.
What happens when I hire a permanent CTO?
Then the engagement has done its job.
Growing out of a fractional arrangement is the expected outcome, not a failure. I help write the role profile, and sit in on the technical interviews if you want me there.
I brief whoever you hire: architecture, open decisions, and the reasoning behind what is already built. The handover sits in the Statement of Work from the start.
Why is the company registered in Malta, and what does that mean for contracts and invoices?
I live and work in Malta, and Nephelix Nova Ltd. is incorporated there.
For business clients in the EU with a valid VAT ID that means an intra-EU invoice under the reverse-charge procedure; you can verify the VAT ID in the EU VIES register. For clients in the UK the supply falls outside EU VAT, and you account for it under UK rules.
You get a contract under German or Maltese law, by agreement. An NDA and a data processing agreement come on request. Full registration and tax details are in the imprint.
Do you work on site?
I work remotely by default, and travel when it's worth it.
The day-to-day runs through your project board, your repository and your standups, in Central European hours. For a kickoff, an architecture workshop or a difficult stakeholder session, I come to you.
We agree travel in advance and I bill it at cost. Malta is two to three hours by direct flight from most of Central Europe.
Which languages do you work in, and how quickly do you respond?
German and English, in Central European hours (CET/CEST).
That is a full working day on the continent, and all but the last hour of one in the UK. Calls outside that window can be arranged.
I usually answer within one business day, Monday to Saturday.
Contact
Most engagements begin with a single technical question.
A fractional engagement, extra engineering capacity, or a second opinion on one decision. Fifteen minutes is usually enough to find out which.