Hire an AI developer without hiring full time
Fractional AI engineering means a fixed share of my week goes to your product. You get a senior engineer who scopes, builds and ships AI systems end to end, embedded in your team, with few meetings and an agentic working style. No recruiter, no headcount, no full-time contract.
What is fractional AI engineering?
Fractional AI engineering is a fixed share of a senior engineer's week, committed to your product, for as long as you need it. Not a marketplace contractor picking up tickets, not a consultant writing a strategy deck, not a full-time hire with equity and a notice period. You buy capacity and judgement, and you get shipped software.
It exists because the hiring market for AI engineers is brutal for small teams. The salary bands are high, the good people are already busy, and a founder who needs an assistant, an agent workflow or an AI feature in the product usually does not need a full person forever. They need one now, reliably, for part of the week.
Why hire an AI developer part time instead of full time?
- Speed. No job posting, no recruiter, no notice period. Scope by email, then work starts.
- Seniority at a fraction. A part-time senior beats a full-time junior for anything that touches model behaviour, cost and failure modes.
- Reversibility. If the AI part of the roadmap turns out to be smaller than you thought, the engagement ends. A hire does not.
- No management overhead. Agentic-first working style, few meetings, written updates. I do not need a daily standup to make progress.
What does the engagement actually look like?
| Fractional AI engineering | Project work | Full-time hire | |
|---|---|---|---|
| Commitment | A fixed share of my week, ongoing | One defined outcome | Permanent headcount |
| Best for | An evolving roadmap with AI in it | A known system to build | A long-term team you are growing |
| Scope changes | Expected, handled in the cadence | Re-scoped and re-quoted | Internal |
| Ends by | Ending the cadence | Delivery | Resignation or layoff |
| You get | Capacity, judgement, shipped code | A system, handed over | A colleague |
If your need is one bounded system rather than ongoing capacity (a website assistant, for example, sized with the missed inquiries calculator), look at AI automation services instead. If the thing you want is specifically an agent or an assistant, see custom AI agents.
What kind of AI developer is this?
Ten years as a senior 3D and VFX artist came first: Houdini-driven simulation and character effects, with brand credits including Samsung, Adidas and Puma, and recent direct bookings by Wieden+Kennedy and We Are Social. That is where the engineering discipline comes from, because procedural work under production deadlines is not forgiving of vague systems.
The AI work since then is not a portfolio of demos. fahrchat is a live WhatsApp assistant that books real appointments for a paying driving school, on Twilio and Stripe. baselit is a React Native app on the App Store that turns a selfie into a score and a routine. aimentionsyou.com tracks how often ChatGPT, Claude, Perplexity and Gemini mention a brand. Nexus is a private multi-agent system with recursive memory and cross-machine operation, and JobMachine is a fully agentic outreach system that runs daily and unattended. The last two are not for sale; they are the reason I can talk about orchestration from experience rather than from a blog post.
What can I hand over?
The whole path, not a slice of it:
- LLM assistants, agent workflows, retrieval-augmented generation, MCP integrations, on the Claude and Anthropic API stack
- Product engineering in TypeScript, Node.js and Python, React Native and Expo, with App Store shipping
- Infrastructure that has to keep running: Supabase, Vercel, Twilio and the WhatsApp Business API, cron jobs, Playwright for anything that needs a browser
- The unglamorous half: auth, state machines, admin views, error handling, the fallbacks that decide whether a team trusts the system
What cost drivers should I expect?
No price list, no packages. What moves the number: the share of the week you want, how long the engagement runs, how much of the stack I am responsible for, and whether I am also operating what I build. Model and infrastructure usage sits on your accounts, so you see it directly instead of through a markup.
How does hiring work here?
Email, not a funnel. You write what you are building and where it is stuck. I reply with scoping questions, then a written scope, a cadence and a fixed quote. No sales call, no booking widget, no packages, and I will say no if the fit is wrong rather than take the work.
Look at the work and the proof first, then write to hello@marcomori.net or use the contact section. I reply personally, usually within a day.
Questions people ask
Can I hire Marco Mori as a fractional AI developer?
Yes. Fractional AI engineering means a fixed share of my week for your product, for founders and small teams that need senior AI and software work without a full-time hire. Scope and cadence are agreed by email after a short scoping conversation.
What is the difference between a fractional AI engineer and a consultant?
A consultant advises and hands you a document. I ship. The deliverable is working software in your repository, running against your users, plus the decisions written down so your team can carry it.
How do we start?
Email me what you are building and where it is stuck. I reply with scoping questions, then a written scope, a cadence and a fixed quote. No sales call, no booking widget, no packages.
What does hiring an AI developer this way cost?
There is no price list. It is quoted after a short scoping conversation by email, and the drivers are the share of the week you want, how long the engagement runs, and how much of the stack I am responsible for.
Are you available for a full-time role?
No. I run my own products and client work in parallel, which is what keeps the experience current. Fractional is the format, and it is the reason a senior engineer is available at all.
Which languages and time zones do you work in?
English and German. I am based in Germany and work remotely worldwide, flexible across time zones.
Do you work with non-AI parts of the product too?
Yes. Most AI features are ten percent model and ninety percent ordinary software: auth, state, queues, billing, an admin view, App Store shipping. I build all of it, and I will tell you when a problem does not need AI.
Who owns the code?
You do. It lives in your repository from the first commit, and the architecture is written down so the engagement can end without a cliff.
Start with an email. Describe the process that eats your time. I reply with a few scoping questions, then a written scope and a fixed quote. No sales call, no packages.