Do you work on pure equity?

I love working with ambitious founders, and I happily structure hybrid engagements — a reduced service fee combined with equity — when the fit is right. Pure-equity arrangements, however, aren't something I take on. A service fee is required on every project: it ensures focused delivery, protects both sides against misaligned timelines, and keeps the engagement sustainable the same way any senior technical hire is compensated. If you're an early-stage founder, let's talk — there's almost always a structure that works.

How much does a Fractional CTO cost in Europe?

Hourly consulting is €150/hour, day rate is €700/day. Ongoing Fractional CTO retainers start from about €2,100/month for a 2-3 days/month minimum and scale up with the cadence — a 1-day-a-week engagement typically lands between €5,000–€8,000 per month depending on scope. Partnership deals (reduced fee + equity) are available for aligned early-stage startups. All prices exclude VAT and French TVA applies where relevant; EU B2B clients with a valid intra-community VAT number benefit from reverse charge.

Fractional CTO vs full-time CTO — which should I hire?

Hire a full-time CTO when the role genuinely needs 40+ hours/week of executive tech leadership — usually post-Series A with 10+ engineers, a real product in market, and a 3-year roadmap. Hire a Fractional CTO when you need senior technical leadership but: you're pre-seed to Series A, your engineering team is under 10 people, you want to validate the product before committing to a cap-table-impacting hire, or you need a specific expertise (AI strategy, EU compliance, sovereign cloud) that a generalist full-time CTO wouldn't bring.

How does the Partnership model work?

It's a hybrid engagement: a reduced cash rate (typically 30-40% of my standard) combined with equity. The exact split is discussed case by case after we've talked through your stage, timeline, runway, and goals. The service-fee component is always present; it's what keeps the engagement focused and fair to both sides.

What's a typical engagement duration?

Consultations run 30 or 60 minutes. MVPs typically ship in 4-8 weeks. Fractional CTO engagements are usually 2-3 days per month minimum, with the cadence scaling up based on traction and fit. Shorter sprint engagements (1-2 weeks) are also possible for well-scoped prototypes.

Can you help with EU AI Act compliance?

Yes. I help companies classify their AI systems by risk tier (prohibited / high-risk / limited-risk / minimal-risk), implement the technical documentation and post-market monitoring required by Articles 9-15, align with GPAI obligations for foundation-model users, and produce the DPIA, Transfer Impact Assessments (Schrems II), and Article 28 DPAs needed. I also cross-walk with GDPR, NIS2, DORA (for financial services), and ISO/IEC 42001 / 23894. Sign-off always rests with your DPO or legal counsel; what I deliver is a defensible, documented compliance posture.

Can you help us migrate from OpenAI to sovereign infrastructure?

Yes — this is becoming a common request from European companies facing compliance pressure or customer procurement scrutiny. Typical path: audit current OpenAI/Anthropic usage, map workloads by quality/latency/cost sensitivity, select replacement targets (Mistral Large for most chat, self-hosted Llama-3 or Mixtral for sensitive data, Claude Sonnet via Bedrock EU where acceptable), build an eval harness that proves parity, migrate behind a feature flag, and cut over gradually. End state: zero prompt/response egress to non-EU jurisdictions, with an auditable trail.

Do you work with non-technical founders?

Yes — this is one of my most common engagements. Non-technical founders hire me to make the build vs buy decision, run the first hiring, set up the stack, ship the MVP, and represent the company technically with investors, partners, and early customers. I translate between product intent and engineering reality, and write everything in plain language so the founder stays in the loop without needing to code.

Do you work remote or on-site?

Remote-first, based in Paris. I'm open to on-site days in Paris and short on-site sprints across Europe for the right engagements. Most clients are 100% remote with weekly syncs and async daily updates.

How quickly can you start?

Usually within 1-2 weeks of signing. For urgent MVPs or discovery sprints I can often kick off within days, starting with a scoped 3-5 day discovery phase before we commit to the full build.

Yes. Mutual NDAs are standard. I can send you a clean one to start, or sign yours if the terms are reasonable. All client work, product ideas, and internal data stay strictly confidential — during and after the engagement.

Can you join as a technical co-founder?

Rarely, and only for startups I'm deeply aligned with — on mission, market, and long-term collaboration. Equity-heavy co-founder arrangements need mutual conviction on both sides and a realistic path to milestones. More often than not, the Partnership model (reduced service fee + equity) is a better fit for both of us: it gets you senior technical leadership without the co-founder commitment, and it keeps my focus across a handful of great projects rather than locked into one.

Can you work with US or Canadian clients?

Yes — North American clients are a regular part of the practice. Time-zone overlap with the US East Coast is 3-4 synchronous hours daily (your morning, my afternoon), and engagements typically run async-friendly with weekly syncs.

Fractional vs Part-time vs Interim vs Full-time CTO — what is the difference?

Founders comparing CTO models often blur four distinct roles into one decision. The differences in commitment, cost, and accountability are large, and picking the wrong model wastes runway.

The four models

1. Fractional CTO

Part-time, ongoing, typically 2-3 days per month minimum. Cap-table-light or no equity. Engagement structured as a monthly retainer. The Fractional CTO complements rather than replaces founders or an in-house team. Best for seed to Series A startups that need executive technical thinking without committing to a full-time hire.

2. Part-time CTO

Halfway between fractional and full-time. Usually 40-60% of full-time hours, ongoing, often with meaningful equity. Suited to early-stage startups with technical co-founder energy but no full-time CTO commitment yet. Tends to evolve into either Full-time CTO or Fractional CTO as the company matures.

3. Interim CTO

Full-time but fixed-duration — typically 3 to 12 months. Usually fills a gap left by a departed CTO, supports a transition (acquisition, restructuring, fundraise), or stabilises a team in crisis. Cash-heavy compensation, no permanent equity, defined exit. The interim CTO is there to stabilise and hand off, not to build long-term.

4. Full-time CTO

Permanent executive, full-time presence, meaningful equity, cap-table impact. Owns the technical posture of the company across its entire arc. The right hire when the company has clear product-market fit, an engineering team of 10+, and the financial capacity to commit a top-of-market salary.

Quick comparison

Fractional: 2-3 days/month, ongoing, low cap-table impact, embedded leadership without daily presence
Part-time: 40-60% time, ongoing, meaningful equity, deeper engagement than fractional
Interim: full-time, 3-12 months, cash-heavy, fills a gap
Full-time: full-time, permanent, large equity grant, owns the long arc

A decision framework by stage

Pre-seed to Seed

A Fractional CTO usually wins. You need judgment and architectural calls but probably not 40 hours per week of executive presence. The cap-table impact of a full-time CTO at this stage is steep, and the equity you give up may be worth a lot more later than the salary you save now.

Series A

This is where the choice gets harder. If you have a strong VP of Engineering or technical co-founder, Fractional or Part-time often continues to work. If you do not, the case for Full-time strengthens — the team is large enough that an absent leader becomes a bottleneck.

Series B and beyond

Full-time. The team is too large, the technical surface too broad, and the strategic stakes too high for part-time leadership. A Fractional CTO can sometimes still work as advisor to a Full-time CTO, but the day-to-day role belongs to a full-time hire.

Special case: stable team without a CTO

If you have a competent existing team and need senior advisory rather than daily leadership, Fractional fits well across all stages. The engagement is more "technical board member" than "embedded leader" in this configuration.

Common mistakes

Hiring full-time too early. Burns runway on a salary the company cannot support and saddles the cap table with equity that should have been preserved.
Hiring fractional too late. By the time the team is 15+ engineers, fractional cadence is too thin for the operational load.
Treating an interim CTO like a full-time CTO. Interim is for stabilisation and handoff, not strategy redirection.
Under-scoping a part-time CTO. Part-time at 50% must be structured deliberately — what they do and what they do not do — or it collapses into either too little or too much.

Bottom line

The four models solve different problems and the right one depends primarily on your stage and team shape. Fractional CTO at Insightrix is structured for the seed-to-Series-A window where most startups need executive technical thinking without the full-time commitment. If you want a tailored answer for your company, submit a project brief.

Editorial content. Informational only — not legal, financial, or professional advice.