Senior AI Product Developer

NANCE; Nieuw-Vennep; Hybrid; EUR 80,000 - 100,000; Full time

Benefits offered by this job

Salary range 80k–100k EUR

Equity

Visa sponsorship

Hybrid work

Flexible hours

Job summary

Nance is seeking a Senior AI Product Developer to own user-facing features end-to-end in a fast-moving, high-ownership team. You’ll decide what to build from thin specs, prototype quickly, ship to production and measure impact.

You’ll improve the Nance agent, build eval harnesses, and collaborate across frontend React, Python backend and cloud infra. The role emphasizes UX, speed, polish, and hands-on coding with AI tools.

Qualifications

• 5+ years of professional software engineering with customer-facing product work.
• Shipped at least one LLM-powered feature to production for real users.
• Strong full-stack fundamentals and attention to UX, speed and polish.
• Fluent in English; Dutch is a plus but not required.

Responsibilities

• Work on core capabilities of the Nance agent: harness, tools and memory management.
• Build evals and experiment with techniques to observe and test agent behavior.
• Take features from idea to shipped and adopted: scope, full-stack implementation, launch and iterate.
• Ensure UX, speed and polish are integral to the product.
• Leverage AI coding tools daily to raise team-wide capabilities.

Skills

Full-stack development

UX polish

AI tooling fluency

Customer-facing product work

English proficiency

Tools

React

Python

Google Cloud

Job description

At Nance we’re looking for a Senior AI Product Developer to join our team.

About Nance

Nance is an AI financial controller colleague: an agent that works across the whole financial stack, from accounting software like ERPs to broader business software like email and Slack. She helps finance teams and accountants get mundane tasks done and derives complex insights from diverse data sources. Our mission is to make Nance feel and operate like the best finance employee anyone has ever hired.

As a team we believe fast iteration can only happen in an environment with minimal process, individual agency and trust in each other’s work.

We’re a small engineering team with a high bar and few layers of process. You’ll report directly to our hands‑on founding team.

The role

You’ll own user‑facing product features end-to-end. That means deciding what to build from thin specs and direct user signal, prototyping quickly, shipping to production, and measuring whether it actually works. There’s no handoff: no waiting for a product manager to write the spec, and no separate team to throw a prototype over the wall to.

A large part of the product is the agent itself. You’ll ship improvements to what it can do, and just as important: build the evaluation muscle to know whether a change made it better.

What you’ll do

• Work on the core capabilities of the Nance agent: the agent harness, tools and supporting features like memory management.

• Help solve the observability issues that come with AI software, by building evals and experimenting with bleeding‑edge techniques for the open question of how to observe and test agent behavior.

• Take product features from idea to shipped and adopted: shape the scope, build the full stack (React frontend, Python backend, Google Cloud infra), launch, instrument and iterate.

• Sweat the details: UX, speed and polish are part of the job.

• Use AI coding tools as a default part of your daily workflow, and help raise the bar for how the whole team uses them.

What we’re looking for

• 5+ years of professional software engineering, with meaningful time on customer‑facing product work.

• You’ve shipped at least one LLM‑powered feature to production for real users, and you can tell us how you knew it worked.

• Strong full‑stack experience. Knowing software engineering fundamentals matters more than knowing the details of our stack.

• Product sensibility: you care about UX, speed and polish, and you push back when something doesn’t feel right.

• Comfortable without PM overhead: you’ve worked in a small, high‑ownership team where engineers shape the problem, not just the solution.

• Fluent daily user of AI coding tools (Claude Code, Codex or similar) and enthusiastic about them as a way to build software products.

• Rigorous about correctness and data handling.

• Fluent in English. Dutch is a plus, not a requirement.

Bonus points

• Experience with financial data, fintech, or accounting/ERP systems.

• Experience building eval harnesses, experimentation infrastructure, or A/B testing for AI features.

What we offer

• €80.000 to €100.000 gross per year including holiday allowance, depending on experience.

• Equity in Nance, above the market average.

• Visa sponsorship available.

• The opportunity to join an incredibly fast‑moving team and company.

• Hybrid working and flexible hours.