---
title: 'Senior Backend Engineer - Bookings at SumUp'
canonical: 'https://feeny.ai/job/senior-backend-engineer-bookings-sumup-warsaw-27tcjedvt0b5'
type: 'job'
last_seen: '2026-09-08'
---

# Senior Backend Engineer - Bookings at SumUp

- **Company:** SumUp
- **Location:** Warsaw, Poland / Warszawa Masovian Voivodeship, Poland
- **Posted:** 2026-05-13
- **Last confirmed live:** 2026-09-08
- **Apply:** https://sumup.com/careers/positions/8508079002?gh_jid=8508079002

## Job description

Salary range: 18 850 - 29 660 PLN per month

## About SumUp

Be empowered to do more that matters.

At SumUp, we're on a mission to empower small businesses across the globe by providing a vast set of simple and affordable business tools to help them start, run, and grow their businesses. Today, over 4 million businesses in 36 markets rely on SumUp as their financial partner to manage payments, finance and customer relationships.

## About the Team

You’ll join the[Sell Online Tribe](https://www.sumup.com/en-gb/online-store/), the group shaping how merchants bring their businesses to life online. We design and build tools that help millions of entrepreneurs, from barbers to bakers, sell their products and services anywhere. Our focus is on Online Store and Bookings, two products at the heart of SumUp’s ecosystem. Together, they give merchants the power to manage appointments, showcase their offerings, and get paid—all from their phones.

We’re a cross-functional team of Product Managers, Designers, and Engineers who move fast, collaborate openly, and care deeply about crafting beautiful, performant mobile experiences. As part of this team, you’ll help us expand into new verticals, close the feature gap, enabling us to position our product as a complete and competitive solution for small merchants, and make digital selling effortless for small businesses everywhere.

## What You’ll Do

- Design, build, and maintain scalable backend systems supporting SumUp’s Bookings product
- Collaborate with frontend and mobile engineers to deliver new features and improve APIs across web, iOS, and Android
- Participate in technical planning, code reviews, and design discussions to ensure clean, testable, and maintainable code
- Continuously optimise performance, ensure observability, and uphold our high reliability standards
- Actively contribute to shaping the technical roadmap for the Sell Online platform

You’ll Be Great for This Role If

- You have 5+ years of professional backend engineering experience
- You’re fluent in Kotlin (or Java) and have deep experience with Spring Boot
- You’ve worked with PostgreSQL, Kafka, Docker, Kubernetes, and AWS
- You understand RESTful APIs, distributed systems, and event-driven architectures (e.g. CQRS, Event Sourcing)
- You bring experience with CI/CD pipelines, GitHub Actions, and observability tools like Grafana or Honeycomb
- You thrive in collaborative teams, enjoy mentoring peers, and care about delivering real value to merchants
- (Nice to have) Familiarity with gRPC, Protobuf, or performance optimisation at the backend/database level

## Why You Should Join SumUp 🇵🇱

🌎 Opportunity to work from our vibrant Warsaw office in the Hala Koszyki. This involves a hybrid setup

🌈 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

🚀 Enrolment onto our Virtual Stock Option programme: you will own a stake in SumUp's future success

📚 A dedicated annual L&D budget of €2000 for your individual development, which can be used to attend conferences and/or advance your career through further education

🚴 Fitness support: work out on-site at our gym or explore the city using the Multisport Card, subsidised by SumUp for access to sports facilities across Warsaw

🩺 Commitment to well-being: access health insurance coverage for you and your family, plus life insurance to further protect your peace of mind

🏖 Generous time off: enjoy 26 days of paid leave plus public holidays and special leave days

🌴 Break4me: 1-month sabbatical after 3 years of service

🔗 Referral Bonus: earn additional rewards by referring talented individuals to join the SumUp team

*Disclaimer

The stated salary range represents the expected compensation for candidates who meet the core requirements of this role. Offers above this range may be considered in exceptional circumstances, subject to internal review and approval, where a candidate's qualifications, skills, or experience significantly exceed the role's standard expectations. Job Application Tip

We recognise that candidates feel they need to meet 100% of the job criteria in order to apply for a job. Please note that this is only a guide. If you don’t tick every box, it’s ok too because it means you have room to learn and develop your career at SumUp.

## About SumUp

## Company Overview
- **One-liner**: SumUp is a global fintech company that provides simple, affordable payment and financial management tools to help small businesses start, run, and grow.
- **Entity Type**: Private (Funding stage not publicly available)
- **Headquarters**: London, United Kingdom
- **Founded**: 2012
- **Founders**: Not specified in provided sources

## Core Business
- **Primary industry**: Financial Services / Fintech (Payments)
- **Target customers**: Small and medium-sized businesses (SMBs), B2B
- **Mission or purpose statement**: "Empower small businesses all over the world." — with the vision of "a world where everyone can build a thriving business."

## Products & Services
- **Payment Processing (Card Readers & POS)**: Hardware and software solutions for in-person and online payments, enabling merchants to accept card and contactless payments.
- **SumUp Business Account**: A digital business account for managing finances and transactions.
- **Invoicing & Customer Relationship Tools**: Tools to create invoices, manage customers, and streamline operations.

## Market Standing
- **Valuation/Market Cap**: Not disclosed (private company)
- **Key Metric**: Over 4 million merchants served across 37 markets; 3,000+ employees from more than 90 nationalities
- **Notable Investors/Partners**: Not listed in provided sources
- **Growth Signals**: Headcount growth to 3,000+; recognition as a Top Global Employer for inclusion (Stonewall Workplace Equality Index 2022/2023) and Fintech Diversity Initiative of the Year (2025); expansion across 4 continents with 20+ offices.

## Competitive Advantages
- **Global reach**: Operating in 37 markets with localized products and support.
- **Merchant focus**: Deep commitment to small business owners, with products designed specifically for their needs.
- **Inclusive culture**: Strong diversity and inclusion programs, gender parity in workforce, and employee-led communities (e.g., Pride Club).
- **Autonomous teams**: Small, empowered teams with servant leadership, fostering innovation and speed.

## Strategic Focus
- Expanding product and service portfolio to become a complete financial partner for small businesses.
- Continuing to invest in a learning culture (SumUp University) and employee development.
- Maintaining an office-first culture while enabling occasional remote work to balance collaboration and flexibility.
- Growing market presence by entering new geographies and deepening existing ones.

## Why Work Here
- **Culture**: Office-first company that values human connection, autonomy, and continuous learning. Core values include Team First, We Care, and Founder’s Mentality.
- **Remote/Hybrid policy**: Office-first with the ability to work remotely occasionally, as agreed with teams.
- **Benefits**: Relocation support for overseas hires, dedicated budget for conferences and external training, and location-specific perks.
- **Engineering culture**: Autonomous teams, servant leadership, and a focus on pragmatic, self-driven problem-solving.
- **Inclusion**: Recognized as a Top Global Employer for inclusion; active LGBTQ+ community and gender parity initiatives.
- **Hiring process**: Transparent, with recruiter screening, hiring manager interview, technical assessment, team interview, bar raiser, and final offer.

## Sources
1. [sumup.com](https://www.sumup.com/careers/)
2. [linkedin.com](https://www.linkedin.com/company/sumup)
3. [sumup.com](https://www.sumup.com/careers/culture/)
4. [sumup.com](https://www.sumup.com/careers/positions/)
5. [sumup.com](https://www.sumup.com/careers/how-we-hire/)

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