Senior Java Developer - Core banking

What we build

Megasol builds Corniche, a core banking system that has been in production for 26 years and is still evolving every week. It is the infrastructure behind mobile banks and online banks: customer and account management, loans, cards and payments.

When a customer opens an account, takes out a loan, pays with their card or receives a payment, Corniche handles it. Svea Bank, Sambla and Avarda, Sweden’s second largest player (after Klarna) in invoice and instalment payments, are some of the banks and fintechs running the platform. It covers current and savings accounts, term deposits, consumer loans and much more. Banks integrate through stable, versioned REST APIs and run Corniche as SaaS, in their own cloud or on-premises.

Several new customers are expected to go live in early 2027, and several more are in late-stage discussions. That’s a lot of growth for a team of 11 developers, so we’re adding experienced Java developers now, as the first step in a longer plan. Next, we’ll build up operations and work with AI, including running local LLMs. Joining now means you’ll be part of shaping how the team and the company grow.

Why this is interesting

• Real systems, real money. This is not a side feature. You build the core that banks depend on to stay open, correct and compliant.

• Short path from idea to production. We release every week. A customer request can go from design to live in a few weeks, and you follow it all the way.

• Close to the customer. Customer support and developers collaborate closely together and you will have quick channels to the people who actually use what you build, and understand why it matters.

• Hard, honest engineering problems. Multi-currency, multi-entity, multi-jurisdiction, audit trails on every transaction, a large interconnected codebase. Getting it right takes careful design, and you get the time to do it carefully.

• A place to grow. The development team is the heart of Megasol and the natural starting point for every other role in the company, whether that’s architecture, operations, customer work or AI.

Your role

You will join the team that develops Corniche and take ownership of features from start to finish: refinement and design, implementation, code review, testing support and release. Test engineers help with validation, but you make sure what you build is robust and maintainable from the start.

Because the system is large and highly connected, a change in one place often affects others. Part of the job is understanding those dependencies and making sure changes land smoothly in production. You will work both independently on well-defined tasks and together with other developers, including pair programming, on larger designs and harder problems.

What you will do

• Turn customer requirements from banks and lenders into technical solutions

• Design new functionality and architecture together with the team

• Write high-quality, maintainable Java code

• Review code and help keep quality high across the team

• Take responsibility for delivering production-ready solutions

Who you are

• 5+ years of professional experience with Java

• A degree in computer science or equivalent experience

• Detail-oriented, patient and methodical with complex systems

• Motivated by building solid solutions to real customer problems

• A team player who shares responsibility

• Fluent in Swedish, written and spoken

Bonus if you have

• Experience with Spring and SQL

• Front-end experience with Kotlin and Angular

• Interest in distributed systems and messaging (e.g. NATS)

• Experience from financial or administrative systems (helpful, but not required, we will teach you banking)

What we offer

A small, close-knit team where you know everyone, including the people who built Corniche. Real ownership from day one, flexible hours and a humane pace: careful engineering, no crunch and no busywork.

We work office-first in Uppsala because we believe the best collaboration happens in person, with flexibility when it makes sense for you and the team.