Senior Backend Engineer (f/m/x)

Tomorrow

6d • Hybrid

About The Position

We have big plans for Tomorrow. Our vision: establish sustainable finance at the heart of society. That's a hell of a lot of work, so let's get started. Behind our banking app is a backend that moves real money for real people, safely and every single day. As a Senior Backend Engineer (f/m/x) in a cross-functional product team, the people behind banking, transactions, and investing, you help shape the services at the heart of it. You'll work on a JVM backend (Kotlin and Java, Spring Boot) built around clean domain modelling, event-driven services and a high bar for quality, in a regulated financial environment where correctness and trust are not optional. You will collaborate closely and proactively with other backend and mobile engineers, designers and business owners in an agile setting with regular release cycles. Our flat organizational structure and streamlined decision-making promote a practical, collaborative atmosphere where your input shapes the architecture, how we work, and the people around you. We build in collaboration with AI. Coding tools live in our repositories with guardrails and human review, and you stay accountable for what ships. We want someone who directs these tools well, stays critical of their output, and helps the team level up: building and sharing our AI harness, the reusable tooling and guardrails around the models, rather than keeping it to themselves.

Requirements

• Experience taking features or epics from idea to production. You've been responsible for a meaningful part of a product, working closely with others to get there.
• Backend depth in production. Several years building and running production backend services on the JVM (Kotlin and/or Java with Spring Boot), including event-driven systems (e.g. Kafka), PostgreSQL, and testing as a habit.
• You make teams better. A clear communicator who reviews, pairs, mentors and disagrees constructively.
• You work well with AI. Comfortable directing AI coding tools, reviewing their output critically and keeping ownership of what ships.
• Fluent English , our company language. German is not required.
• You support the idea of creating a better future for everyone by using money as a force for good.

Nice To Haves

• Bonus if you've built or shared reusable tooling (an "AI harness") that lifted a team.
• Bonus: experience in a regulated or safety-critical domain (fintech, banking, payments, health).

Responsibilities

• Designing, building and evolving backend services in our product domain (banking, transactions, investing)
• Modelling complex financial domains cleanly and keeping our architecture healthy as it grows
• Raising the bar on testing, reliability and observability, and helping others do the same
• Taking part in code review, incident management and safe, well-coordinated releases
• Using and improving our AI harness, and sharing what works with the wider engineering team

Benefits

• Working from home and mobile work are integral parts of our remote-friendly work culture.
• The office is available to you any time. It is wheelchair-accessible, has ground-level access and offers flexible options for designing your workspace.

What This Job Offers

• Job Type: Part-time
• Career Level: Senior
• Education Level: No Education Listed