Senior Full Stack Engineer (AI/Backend Focus) – Bonafi B.V.

Full Stack Engineer

Bonafi B.V. · Rotterdam · Full-time, on-site · Start 01/11

Before you apply

• You need to already live in the Netherlands and have the right to work here.
• We cannot offer relocation but can offer visa sponsorship for this role
• We work from our office in Rotterdam five days a week. This is not a remote or hybrid position.
• We are in an intense stage of the company. The contract is for 40 hours per week, but in practice the team currently works considerably more at times, including some evenings and occasional weekends. We prefer to be transparent about that upfront, so you know what the current reality looks like.

About Bonafi

Bonafi is building the operating system for modern family offices.

Families with €10 million or more in wealth often manage their financial lives across banks, accountants, asset managers, funds, legal entities and advisers. Information is fragmented, administration is largely manual and no system has a complete, continuously updated view.

We are building that system.

The first layer is the financial record: one place for the complete wealth structure, with every number traceable back to its original source. The next layer is execution. Bonafi will increasingly take over the operational work that family offices and advisers still perform manually today: processing reports, tracking obligations, preparing payments, following up on missing information and handling administration across entities and asset classes.

Over time, we believe a significant part of what is currently delivered by a network of advisers can be handled by software, with human experts involved where judgment is genuinely required.

We started Bonafi in April 2026. Today, we are a team of five, have €120k+ in contracted ARR and are fully ISO compliant.

We are still early, but the ambition is large: to build the infrastructure on which the next generation of family offices runs.

What you will work on

You will work across the product, but much of the role will be backend and AI infrastructure.

This includes:

• Building document extraction pipelines that turn reports, statements and other unstructured documents into reliable structured data.
•  Modeling clients, legal entities, assets, valuations and cash flows across different asset classes.
• Building the infrastructure around our AI systems: tool use, routing, evaluations, guardrails and human review for cases where the system should not act autonomously.
• Integrating banks, custodians, accounting software, fund administrators and other financial systems.
• Building and improving parts of the frontend when needed.

You will not be limited to a narrowly defined set of tickets. We usually start with a customer problem and expect engineers to help determine how to solve it.

Our stack

Our main stack is:

• Python and FastAPI
• TypeScript, React and Next.js
• PostgreSQL
• GCP, with production infrastructure in Eemshaven
• Cloudflare R2
• Vercel in Frankfurt

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• Voyage for embeddings

All production compute and client data remain within the EU. That is a hard requirement for our infrastructure and architecture.

What we are looking for

We are looking for someone with at least three years of professional software engineering experience, preferably working on products used by real customers in production.

You should be comfortable with:

• Python: FastAPI, async programming, typing, testing and data processing.
• TypeScript and React/Next.js: enough to independently build and ship product features from backend to frontend.
• SQL and data modelling: including designing schemas for complex and imperfect real-world domains.
• LLM-based systems: such as retrieval, structured extraction, agent workflows and evaluation.

Experience with financial software, Dutch tax, accounting or wealth management is useful, but not required.

Our working language is English, so you need to be comfortable communicating and working in English.

Compensation and benefits

The salary range for this role is €4,000 to €5,500 gross per month, depending on experience, excluding 8% holiday allowance.

In addition:

• 0.3% to 0.6% equity in the form of certificates through our STAK. This is the same structure used for our founding engineers. 25% vests after completion of your first contract, with the remainder vesting monthly over the following three years.

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• We do not track vacation days, but in the contract we incorporate: 24 holidays per year, in addition to Dutch public holidays.
• MacBook Pro for work.
• Swapfiets.
• Gym membership in consultation.
• Dinner at the office when we work late.

We start with a 12-month contract, with the intention to continue afterwards if it works well for both sides.

Hiring process

Our hiring process is straightforward:

1. A 30-minute conversation with Cecé.
2. A technical case at our office in Rotterdam.
3. A trial day under NDA, working with the actual Bonafi codebase.
4. An offer if both sides want to continue.

We aim to complete the process within two weeks.

Apply

Apply through this page with your CV and/or GitHub profile and a few lines about the most difficult thing you have shipped.