Senior Backend Engineer - Commercial Systems and Intelligence

SumUp

Contract type

Ongoing

Work mode

On-site · On-site (see listing for address)

Experience

Senior · Not stated

Level inferred from job title

Job description

Aggregate data from across the SumUp ecosystem to determine which acquisition channel or sales agent drove a merchant to take a valuable action (e.g. signing up, adopting a product)
Establish data models, API contracts, and rule definitions that automate existing manual commission workflows for field and tele-sales agents, partnerships and merchant referrals
Build internal backoffices and APIs for sales representatives and leaders to monitor commission and modify commission plans, manage portfolios and resolve disputes
Define and document API contracts, schemas, and integration patterns that other engineering teams can adopt confidently
Establish best practices for testing, observability, and incident response within a newly formed squad
Use AI and agentic coding tools deliberately, to scaffold services, write tests, explore unfamiliar code, and draft documentation while maintaining full accountability for what gets shipped
Company mission
SumUp builds large-scale fintech products used by millions of businesses worldwide

Core technologies

Opportunity to work with SumUppers globally on large-scale fintech products used by millions of businesses worldwide, from our Berlin office. This involves an office-first setup
We take learning and experimentation seriously with Hack Days every second Friday, and entire global Hack Weeks
Commitment to Diversity and Inclusion: Be part of a workplace that values and promotes diversity, fostering an inclusive environment where everyone's perspectives are respected and embraced
A dedicated annual L&D budget of €2,000 for attending conferences and/or advancing your career through further education
Enrolment onto our VSOP program: You will own a stake in SumUp's future success
A corporate pension scheme where we match up to 20% of your contributions
30 Days Sabbatical: Enjoy the unique opportunity to take a well-deserved break with our 30 days sabbatical benefit after completing 3 years of employment with SumUp
Referral Bonus: Earn additional rewards by referring talented individuals to join the SumUp team
Numerous other benefits such as Urban Sports

Bring a strong backend engineering background in Go, or are a typed-language generalist ready to ramp up quickly
Have designed APIs and distributed systems with clear contracts, versioning, and integration patterns
Are fluent in relational and analytical databases (PostgreSQL, Snowflake) and comfortable making the right choice for the right use case
Have built Kafka-based, event-driven systems and understand event sourcing and CDC patterns
Have experience in auditable, high-trust systems where every decision must be traceable — fintech, payments, or similar domains
Have built services from scratch in greenfield, early-stage squads with limited prior context, and are energized, not unsettled, by that challenge
Have experience with testing, observability, and incident response practices and treat them as first-class concerns, not afterthoughts
Are resourceful and adaptable, you take end-to-end ownership, do more with less, and adjust quickly as priorities shift
Can bridge technical and non-technical audiences, translating fuzzy problems into clear engineering work and explaining trade-offs to engineers and sales stakeholders alike
Are pragmatic, you know when good enough ships value and when something genuinely needs to be done properly
Have mentorship instincts, you raise the bar for the people around you, not just your own output
Go, PostgreSQL, Snowflake, Kafka
Go