AI-Native Full Stack Engineer

About Oper

Oper, a European Fintech company, is a leader in cloud-based digital mortgage software. We provide personalised journeys for borrowers and lenders. Oper's technology streamlines the mortgage application process, eliminates paperwork, and increases transparency. Currently collaborating with 16 leading financial institutions across 6 European countries, our digital solutions result in a +27% increase in digital customer conversion, +81% faster mortgage decisions, and a 90% first-time-right rate.

Oper's AI Analyst, Herman, is a mortgage underwriting agent that automates document validation, data extraction, fact-checking, and credit policy application to deliver fully explainable, decision-ready loan recommendations in minutes instead of hours.

A passionate and engaging team of over 30 stellar Fintech operators works vigorously to transform European mortgages by enhancing efficiency and alleviating borrower anxiety. Backed by Bessemer Venture Partners and Motive Ventures, our SaaS platform has raised EUR 14 million, placing Oper at the forefront of revolutionising mortgages in Europe. Oper currently has offices in Zürich, Switzerland, and Antwerp, Belgium.

Now, we’re looking for an AI-Native Full Stack Engineer to join our mission and help shape the future of automated mortgages in Europe and beyond.

Building an AI-Native Services Organisation

We believe the way software companies build products and deliver them to customers is about to change fundamentally. The old boundaries between product engineering, customer implementation, and customer success are dissolving. We are building Oper as an AI-native organisation where agents do real work across that whole chain: scaffolding features from a spec, drafting customer configuration, generating tests and documentation, and removing the repetitive work that used to sit between teams.

This is in motion, not finished, and that is the point. We are looking for people who want to help define what an AI-native model actually looks like in practice, not just apply one that already exists. If you want to be at the leading edge of how services and product organisations work, this is a place to shape it.

Your Mission

In this role, you will design, build, and ship product and customer-facing software across Oper’s platform. You will work across the full stack, from back-end services, APIs, integrations, and data flows to front-end user journeys and internal tooling. Your work will span core product capabilities, customer-specific configuration, implementation accelerators, and automation that helps us deliver faster and better.

This is a role for someone who is AI-native: you use modern AI tooling as a core part of how you think, build, test, review, and ship. You are not joining a separate “CS engineering” or “product engineering” track. You will work where the highest-value engineering problems are, moving between product development, customer implementations, integrations, and operational tooling as priorities evolve.

Your Responsibilities

What you’ll do

• Build and improve full-stack features across Oper’s platform, using Python on the back end and Angular on the front end.
• Design and implement robust APIs, integrations, micro-services, data flows, and configuration logic.
• Turn product, customer, and operational requirements into reliable technical solutions.
• Work on both generic product capabilities and customer-specific implementation needs, avoiding unnecessary one-off work where a reusable pattern is possible.
• Collaborate closely with Product, Engineering, Customer Success, and Operations to understand priorities, trade-offs, and delivery constraints.
• Be comfortable working directly with customers, system integrators, and internal stakeholders when technical clarity is needed.
• Own quality end to end: architecture, implementation, testing, review, deployment readiness, and operational follow-up.

Work AI-native

We expect you to use modern AI tooling as a real lever, not a curiosity.

• Write code AI-first: agents produce a meaningful share of your code under your direction, while you own the architecture, integrations, review, and quality. We measure your output in shipped customer value, not hand-typed lines.
• Build agentic workflows that do real work: scaffolding features and services from a spec, generating and running tests, drafting configuration logic, reviewing diffs, producing technical documentation, and accelerating debugging.
• Use modern AI coding tooling as the default way you build, configure, test, and review, not as an occasional helper.
• Identify where AI compounds your work and where it does not, and design your workflow accordingly.
• Aim for a delivery cadence a non-AI-native engineer simply cannot match, and help us raise the bar on what an AI-native engineering function looks like at Oper.

Your Profile

What you’ll bring

• 3 to 5 years of experience in software development.
• Full-stack experience with Python (Django or FastAPI) on the back end and Angular on the front end.
• Solid experience with REST APIs and integration work, comfortable shipping across the full stack from Angular front ends to Python services.
• Experience building maintainable software in environments where requirements can be flexible, incomplete, or fast-changing.
• Ability to translate business, product, and customer context into pragmatic technical choices.
• Strong product sense: you care about the user journey, operational impact, and long-term maintainability, not only the code.
• Awareness of security best practices and data protection principles, especially when working with financial or sensitive data.
• Excellent communication skills, including the ability to explain technical trade-offs clearly to non-technical stakeholders.
• Ambition to learn, experiment, and grow while staying humble and open-minded.
• Fluency in English; additional languages such as Dutch, French, or German are a plus.
• Experience in financial services, SaaS, mortgage technology, or a scale-up environment is a plus.

Location & Setup

• Belgium-based candidates: hybrid setup with 2 to 3 days per week in our Antwerp office.
• Working in CET hours.
• Reporting line depends on team setup and seniority.

As a fast-growing fintech, we're building a team where you can truly make an impact.

We offer:

• Competitive annual salary, depending on experience
• Employee stock options
• 25 vacation days per year + 1 paid mental health day
• Dynamic international team with 12 nationalities
• Supportive, inclusive, and collaborative culture
• Learning & Development budget with dedicated time for growth
• Structured onboarding with a dedicated mentor
• Annual company-wide Team G2G in an inspiring location
• Extra-legal benefits depending on your location
• Full support with local administration
• Health insurance and pension scheme
• Flexible working hours
• All equipment needed to do your best work

Inclusive at Our Core

Oper is an equal opportunity employer. We celebrate diversity and are committed to creating an inclusive environment for all employees and contractors. All applications are considered without regard to race, religion, gender, gender identity, sexual orientation, disability, age, or any other protected status.