Senior Staff Engineer (Mollie Connect)

We are a FinTech company from Amsterdam that helps businesses of all sizes accept online payments. With simple and clear products, we offer an accessible platform with the most important payment methods at a fair price. We are dedicated to making payments easier for our users, offering powerful yet simple options. We are Mollie, a pioneer in the payment industry.

Mollie has grown rapidly since its inception. Currently, we’re processing close to €20 billion per year, and we have the ambitious goal of becoming the most loved payment service provider in Europe. And to do that, we need to create products that scale across multiple markets and currencies, while also continuing to innovate quickly and be resilient as a critical infrastructure provider.

Now we’re looking for a Senior Staff Engineer to join our Mollie Connect team. Mollie Connect is our API that allows platforms and marketplaces to easily onboard merchants and accept payments on their behalf. You will be responsible for a large part of the payment product that we offer to our customers. This product is crucial to our overall strategy. In this role you will be focusing on the entire software lifecycle and use your experience to contribute to solving complex technical challenges within the team and across the organisation. You will champion and implement both good engineering practices and architectural ones.

What you'll be doing:

• Design, build, and maintain the platform and systems that underpin Connect.
• Enable other teams to build solutions on top of Connect.
• Architect, design, and implement secure, fault-tolerant, and performant solutions for distributed systems, ensuring high availability and scalability.
• Collaborate with engineering leadership and product teams across the organization.
• Lead by example in writing clean, well-tested, and maintainable code.
• Mentor and coach other senior engineers in their technical design and decision-making.
• Take on high-impact projects, making key technical decisions that shape the future of our product offerings and architecture.

What you'll need:

• 10+ years of experience in backend development, with significant experience in distributed systems.
• Strong expertise in a modern backend language (e.g., PHP, Java, Kotlin, Scala, Go, C#).
• An architectural understanding of AWS (e.g. DynamoDB, Lambda, ECS) or another cloud provider.
• Experience working with SQL/NoSQL databases.
• Ability to communicate complex technical details to both technical and non-technical audiences.
• Demonstrated ability to drive technical projects with end-to-end ownership.
• Strong analytical and problem-solving skills.
• Previous experience as a Staff Engineer or a similar senior technical leadership role.

Good to have:

• Experience with PHP and/or Kotlin.
• Familiarity with event-driven architectures and message queues (e.g., Kafka, RabbitMQ).
• Experience in the FinTech industry or with payment processing systems.
• Experience in building and maintaining APIs for external developers.

Some of the tools we use:

PHP, Kotlin, MySQL, Kafka, Kinesis, DynamoDB, Redis, Elasticsearch, AWS, Docker, Kubernetes, Jenkins, Git, PagerDuty, Grafana, Prometheus.

Nice to know about Mollie:

At Mollie, we love building products that simplify complex financial services. Our product is simple and intuitive and we are obsessed with providing the best customer service.

We are entrepreneurs at heart. We are growing and scaling fast and we are still only at the beginning of our journey.

Being a Mollie means that you will work with people who are curious by nature, always looking for ways to improve, and obsessed with the details.

This is what we offer:

We know how important a healthy work-life balance is, we want to support you in this as a company. In addition to a competitive salary, you can expect:

• Choose your own device. Pick up to £1,500 to spend on your favorite tech, no questions asked.
• Pension plan. We offer an excellent pension plan to prepare you for the future.
• Holiday allowance. In most countries, you get 25 days of annual leave, plus any national holidays. In the Netherlands, an additional 8% holiday allowance is added to your salary.
• Flexible working. Hybrid meeting means that you can decide with your team if you want to work from home, or the office, or a mix of both. We consider 3 days in the office ideal for collaboration.
• Learning and development budget. We want you to grow. That's why we have a budget for personal development which is up to £1,000 per year.
• Travel expenses. A Mollie card to cover all your travel expenses if you want to come to the office. Our offices are located near train stations.
• Sports and wellbeing. Your wellbeing is important to us. That's why every Mollie gets access to a company fitness plan, paid for by Mollie.
• Food and drinks. Healthy food and snacks are available in all our offices. Always fresh, always delicious.
• Annual return flight. For employees working from outside their country of hire, we offer one return flight per year to your country of hire. In addition to this, we will also provide accommodation for one week while you're in town. Conditions apply.
• Relocation support. We'll help you move to the country you'll be working in, including temporary housing, and assistance with your visa.
• Bonus program. A discretionary bonus programme applicable to all Mollies.
• Stock options. Each Mollie receives a package of stock options. These have a lot of potential to grow in value.

Being a Mollie means that you will work in an international environment with colleagues from all parts of the world. We offer an international culture where we celebrate our different backgrounds and perspectives. We believe in providing equal opportunities to all and encourage everyone to apply for positions that match their interests and experience, regardless of gender, race, religious beliefs, age, disability, sexual orientation, or any other protected characteristics.