---
titel: "Fractional CTO in Switzerland · Ivo Schönberner"
url: https://sacosi.ch/en/fractional-cto
seite: /en/fractional-cto
stand: 2026-09-24
beschreibung: "Ivo Schönberner as fractional or interim CTO in Zürich and Switzerland: interim technical leadership, due diligence readiness, clean handover to a permanent CTO."
---

> Knowledge version of the page https://sacosi.ch/en/fractional-cto. It contains the full text, including what is shortened or collapsible on the page itself. Publisher: SACOSI, Situational Awareness Consulting by Ivo Schönberner, Zürich.

# Fractional CTO for start-ups and scale-ups.

**Short answer:** As Fractional CTO, I take on the technical leadership of your company part time or for a defined period: architecture, team, security and due diligence readiness. I work according to Situational Awareness: technology follows your business model, not the other way round. The goal is the handover to a permanent CTO or to your team.

## When do you need a Fractional CTO?

When technical leadership is needed quickly, but a full-time role does not yet fit or has not yet been filled.

### There is no CTO

The product is growing, and decisions on architecture and team are made on the side.

### The CTO is leaving

Knowledge risks being lost, the team needs leadership, and the search takes time.

### Due diligence is coming

Investors want to see architecture, security and scalability, and want it evidenced.

### The platform can no longer carry the load

What was built for a hundred customers breaks at a thousand. Quick fixes become expensive.

## What happens in the first 90 days?

In the first 90 days, a reliable picture of the situation emerges, together with the first wave of decisions the business feels immediately.

- **Days 1 to 30, capturing the situation:** conversations with founders, investors, the team and key customers. Goals, vision, funding stage and runway, core processes, plus architecture, costs and security. Result: the situation picture with a SWOT analysis and process map.
- **Days 31 to 60, understanding the situation:** naming the biggest points of friction between product and technology, making decisions and recording them in the decision log.
- **Days 61 to 90, thinking ahead:** target architecture and roadmap for the next 12 to 24 months, a role profile for the permanent CTO or for expanding the team.
- **Game plan:** target architecture and roadmap from days 61 to 90.

## What do investors want to see in an IT due diligence?

Investors check whether the technology can carry the business model, and whether the knowledge about it depends on more than one person.

- an understandable architecture and the reasoning behind the key decisions
- security, access rights and data protection, evidenced rather than asserted
- scalability and the costs that come with growth
- dependencies on individual people and vendors
- a team and a roadmap that fit the business plan and the funding
- documentation that can be audited, instead of knowledge kept in people's heads

## What can the collaboration look like?

- **Fractional:** one to three days a week over several months.
- **Interim:** full time for a transition period, until the permanent CTO starts.
- **Due diligence sprint:** targeted preparation for a funding round or transaction.

For investors and family offices, the same is available as an engagement within a portfolio holding: [IT situation picture and due diligence](https://sacosi.ch/en/investors). Every format ends with a documented handover. What that looks like is described in the [Situational Awareness method](https://sacosi.ch/en/situational-awareness).

## Questions about the Fractional CTO.

### What does a Fractional CTO do?

A Fractional CTO takes on the technical leadership of a company part time or for a defined period. He is responsible for architecture, technology decisions, security and building the team, without the company having to hire a full-time executive straight away.

### When does a Fractional CTO pay off?

There are typically four situations: there is not yet a CTO, the previous CTO is leaving, a funding round or due diligence is coming up, or the platform can no longer carry the growth. In all four cases, technical leadership is needed quickly, but not necessarily on a permanent basis.

### How much time does Ivo Schönberner invest as Fractional CTO?

That depends on the situation. Typical arrangements are one to three days a week, or a monthly engagement with a fixed scope. The framework is set out in the initial call.

### What is the difference between a Fractional CTO and an Interim CTO?

An Interim CTO usually replaces a missing executive full time for a transition period. A Fractional CTO works part time, often over a longer period. Ivo Schönberner takes on both forms, depending on what the situation calls for.

### Does a Fractional CTO help with an IT due diligence?

Yes. He prepares architecture, security, documentation and the team so that investors can review what they want to review, and accompanies the conversations with the reviewers.

## Do you need technical leadership?

Thirty minutes, no pitch. You describe the situation, I ask questions. Afterwards, we both know whether a situation picture is worthwhile.

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