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Backend Engineer

Backend Engineer

Senior Backend Engineer - Bookings

SumUp

Warsawsenior

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Role 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
, 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.

This is a saved copy of a posting published elsewhere. Postings get taken down without notice — check the employer's site before applying. mentors.coach is not the hiring party.

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On the wheel

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Winners are drawn at random among entries with a confirmed email. The date and the full rules are on the draw page.

Draw rules

Backend Engineer

Senior IT Analyst (B2B)

ALGOTEQUE Innovation Hub

Krakow

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Role description

ALGOTEQUE to firma doradcza IT, która wspiera startupy, średnie i duże przedsiębiorstwa w tworzeniu i wdrażaniu innowacyjnych technologii. Nasz zespół ma udokumentowane sukcesy w projektowaniu, rozwijaniu, wdrażaniu i integracji rozwiązań programistycznych (AI, ML, BI, Web, Automatyzacja) dla branż takich jak telekomunikacja, energetyka, bankowość, ubezpieczenia, farmacja, motoryzacja, przemysł oraz e-commerce. Świadczymy nasze usługi zarówno w modelu fixed-price, jak i time-and-materials, pomagając naszym klientom w osiąganiu ich celów biznesowych i strategii IT.

Job Description

  • Zbieranie i analiza wymagań biznesowych oraz systemowych.
  • Dekompozycja, priorytetyzacja i specyfikacja wymagań funkcjonalnych oraz niefunkcjonalnych.
  • Analiza i opiniowanie proponowanych rozwiązań systemowych.
  • Przygotowywanie dokumentacji, historyjek, modeli procesów, danych i integracji.
  • Udział w projektowaniu architektury systemów oraz modelowaniu danych i procesów.
  • Analiza i projektowanie integracji między systemami.
  • Współpraca z biznesem, deweloperami, testerami, architektami i dostawcami.
  • Przygotowywanie i weryfikacja scenariuszy testowych oraz wsparcie wdrożeń.
  • Prowadzenie spotkań z interesariuszami i wspieranie realizacji inicjatyw w środowisku Agile.
  • Wspieranie przygotowania monitoringu, metryk i raportów na podstawie wiedzy systemowej i biznesowej.
  • Praca zarówno z systemami legacy, jak i nowoczesnymi rozwiązaniami IT.

Profile / Requirements

  • Wykształcenie wyższe techniczne lub pokrewne.
  • Minimum 5 lat doświadczenia w analizie systemowej, biznesowej lub procesowej.
  • Minimum 2 lata doświadczenia w sektorze bankowym oraz 4 lata doświadczenia w IT.
  • Praktyczna znajomość analizy, dokumentowania i dekompozycji wymagań.
  • Znajomość UML, BPMN lub diagramów sekwencji.
  • Znajomość relacyjnych baz danych i SQL.
  • Praktyczna znajomość REST, SOAP i API oraz metod integracji systemów.
  • Znajomość JIRA i Confluence.
  • Praktyczna znajomość metodyk Agile.
  • Umiejętność pozyskiwania i analizy danych oraz informacji od różnych interesariuszy.
  • Umiejętność pracy z systemami legacy i nowoczesnymi rozwiązaniami.
  • Analityczne myślenie, samodzielność i umiejętność rozwiązywania problemów.
  • Bardzo dobre umiejętności komunikacyjne i współpracy z różnymi interesariuszami.
  • Dobra znajomość języka angielskiego na poziomie zaawansowanym.

Mile widziane

  • Doświadczenie w obszarze backoffice, bankomatów, płatności, rozliczeń lub clearingu.
  • Znajomość zagadnień regulacyjnych.
  • Znajomość MQ/SOA lub Kafka i komunikacji event-driven.

Dodatkowe informacje

  • Forma współpracy: B2B.
  • Model współpracy: 100% zdalnie, z możliwością sporadycznego udziału w spotkaniach projektowych w wybranej lokalizacji (Kraków / Katowice / Warszawa).

AO4387

This is a saved copy of a posting published elsewhere. Postings get taken down without notice — check the employer's site before applying. mentors.coach is not the hiring party.

Backend Engineer

Administratorka/Administrator aplikacji rozliczeń i rachunkowości

PKO Bank Polski

Warsaw

Apply on the employer's site

Role description

Na Co Dzień w Naszym Zespole

  • eksploatujesz i administrujesz bankowe aplikacje informatyczne w szczególności z obszaru rozliczeń transakcji skarbowych,
  • monitorujesz, analizujesz i nadzorujesz dostępność i pojemność eksploatowanych aplikacji,
  • realizujesz usługi informatyczne dla jednostek biznesowych banku w zakresie eksploatowanych aplikacji,
  • rozwiązujesz incydenty/problemy zgłaszanych przez jednostki banku z zakresu działania administrowanych aplikacji,
  • prowadzisz dokumentację oraz współpracujesz z dostawcami oprogramowania w zakresie obsługi błędów i problemów eksploatacyjnych,
  • bierzesz udział w pracach zespołów projektowych wdrażających usługi IT,
  • współpracujesz z administratorami zasobów informatycznych w zakresie eksploatowanych aplikacji,
  • bierzesz udział w testowaniu i wdrażaniu poprawek serwisowych i nowych wersji aplikacji.

To Stanowisko Może Być Twoje, Jeśli

  • posiadasz doświadczenie w administracji aplikacjami bankowymi, w rozwiązywaniu problemów i incydentów we współpracy z odbiorcami wewnętrznymi oraz dostawcami wewnętrznymi i zewnętrznymi,
  • masz wiedzę w zakresie eksploatacji i obsługi systemów operacyjnych Linux, MsWindows oraz baz danych MsSQL i Oracle, serwerów aplikacji Tomcat, JBOSS, WebLogic,
  • posiadasz praktyczną znajomość języka zapytań SQL,
  • masz doświadczenie w administracji aplikacjami eCrossBony, Calypso,
  • znasz język angielski na poziomie podstawowym w mowie i piśmie,
  • posiadasz umiejętność pracy w zespole, kreatywność, samodzielność, odpowiedzialność,
  • znasz aplikacje bankowe z obszaru rozliczeń transakcji skarbowych,
  • posiadasz wykształcenie wyższe o profilu informatycznym.

This is a saved copy of a posting published elsewhere. Postings get taken down without notice — check the employer's site before applying. mentors.coach is not the hiring party.

Backend Engineer

Senior IT Analyst (API Domain)

Jit Team

Warsaw

Apply on the employer's site

Role description

Salary:
1000-1140 PLN/day on B2B

Work model:
hybrid from Warsaw (2/3 days per week from the office)

Why choose this offer?

  • You can expect a
    flexible work organization
  • The
    international work environment
    will give you the opportunity to interact with the English language on a daily basis
  • Scandinavian organizational culture
    will provide you with work-life balance, you will gain time for additional training (financed by Jit)
  • The
    Jit community
    will bring you a nice time during regular integration meetings

Project

You will be involved in a financial project focused on
business and data analysis
within the
STO Domain API
.

The role centers on
translating business requirements into clear technical designs
, defining data structures and mappings, and
supporting API contract definitions
. You will collaborate with business stakeholders, consumer teams, and source-system teams to
ensure alignment of requirements
,
data models
, and
system dependencies
. The project also involves establishing business rules,
defining canonical data models
, and supporting
planning activities across delivery teams
.

Responsibilities you'll have

  • Analyse and align business requirements, data models, system flows, and dependencies
    , and translate them into clear technical designs and implementable delivery tasks
  • Design and document services (contracts)
    in and around the
    STO Domain API
    , including rules for transformation logic
  • Support
    contract-first API definition
    with producers, primarily the
    safekeeping system
  • Define
    data mapping
    and the
    canonical data model
  • Raise and coordinate requirements during
    quarterly/PI planning
  • Establish
    business rules
    and valid
    request and response examples

Expected competences and knowledge

  • 5+ years of experience
    in business analysis, data analysis, or related roles
  • Strong data analysis and mapping capabilities
  • Ability to
    translate business rules
    into concrete examples and acceptance criteria
  • Ability to work across
    business, consumer, and source-system teams
  • Understanding of
    custody positions, subpositions, reservations, and corporate actions
  • Knowledge of data description using
    XML, XSLT, JSON, and AVRO

Technologies
you'll work with

  • STO Domain API
  • XML
  • XSLT
  • AVRO
  • JSON

Client
– why choose this particular client from the Jit portfolio?

Jit Team has had an
over-decade-long relationship
with the leading financial group in the Nordic countries, and we are privileged to be our client's premier partner in Poland. At present,
over 200 Jit personnel
are engaged in the completion of
more than 60 projects
for this Norwegian major provider of financial services with a global presence and a strong focus on modern technology. Our customer's work atmosphere is epitomized by the
Scandinavian culture
, which is conducive to people who place emphasis on
work-life balance and feedback culture
. Furthermore, all projects are executed in international teams, giving constant exposure to the English language.

This is a saved copy of a posting published elsewhere. Postings get taken down without notice — check the employer's site before applying. mentors.coach is not the hiring party.

Backend Engineer

IIoT Technical Lead and Developer (Ignition Focus) IRC292576

GlobalLogic

Krakow

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Role description

Description
The client is expanding the Industrial IoT (IIoT) Solution Delivery team with an
Ignition-focused Technical Architect
who

will
design
and
implement
scalable solutions using
Inductive Automation’s Ignition platform
. Able to understand

and migrate one SCADA solution to Ignition. You will complement our ThingWorx + Kepware practice, enabling client to

deliver, integrate, or evaluate Ignition-based solutions across global manufacturing plants while ensuring robust OT/IT

integration and secure cloud connectivity.

Requirements
Ignition Expertise

  • 4–8+ years implementing solutions with Ignition 8.x.
  • Strong hands-on expertise with Gateway architecture, Perspective/Vision, Tag Historian, Alarm

ing, Reporting, SSO, and Gateway Network (multi-site).

  • Proficient in Python/Jython for scripting and automation.
  • Installation of different architecture of SCADA solution (Eg: Monolithic, Enterprise and Hub and

Spoke etc)

Industrial Connectivity & OT

  • Deep knowledge of OPC UA, MQTT (Sparkplug B), Modbus, Ethernet/IP.
  • Practical experience integrating Kepware and connecting to multiple PLC families.
  • Understanding of SCADA/MES concepts, data lifecycles, and shop-floor realities.

Cloud & Enterprise Integration

  • Experience integrating with Azure (e.g., IoT Hub, Event Hubs, Functions, Storage) or similar cloud

platforms.

  • Familiarity with data pipelines and historian/BI integrations.

Security & Compliance

  • Working knowledge of ISA-95 and IEC 62443 principles, certificate management, network segmen

tation, and secure tunneling.

Soft Skills

  • Clear communicator who can align engineers, managers, and non-technical stakeholders.
  • Strong documentation habits; able to create standards and mentor others.
  • Comfortable working in global, multi-cultural environments.

Must Have:

  • Certifications: Ignition Core (minimum) or Gold (ideal);

Nice To Have (Preferred)

  • Azure Architect/IoT; ISA/IEC 62443 training; TOGAF.
  • Experience of migrating Legacy Scada solution to Ignition Solution
  • Experience with ThingWorx (Mashups, Data Models, Edge/SDK) for hybrid estates.
  • Experience with MES concepts (e.g., work orders, genealogy, OEE) and integration patterns.
  • Familiarity with data governance, semantic modeling, and contextualization for analytics.
  • Experience with CI/CD for SCADA/IIoT assets (git, testing frameworks, packaging).

Education:
Bachelor’s degree in Electrical/Electronics/Automation Engineering, Computer Science, Industrial IT, or equivalent experience. Master’s degree is a plus.

Job responsibilities

Architecture & Design

  • Design Ignition architectures (Gateway redundancy, distributed/multi-site, edge deployments).
  • Defining tag models, historian strategy, alarming, reporting, and data flows.
  • Develop integration patterns with Kepware, OPC UA, MQTT (Sparkplug B), databases (SQL Server, Postgres, MySQL), and Azure services.
  • Define hybrid patterns and coexistence strategies with ThingWorx where applicable.

Data Model and Migration

  • Understand Ignition Data model and able to interpret Legacy (Asdaex) SCADA solution and migrate into Ignition.

Implementation Leadership

  • Guide teams on Perspective/Vision, Tag Historian, Alarm Pipelines, SSO/Identity, and scripting (Python/Jython).
  • Establish reusable templates, components, and standards for multi-plant rollouts.

OT/IT Convergence

  • Collaborate with automation engineers integrating PLCs/DCS (Siemens, Rockwell, Mitsubishi, Beckhoff, etc.).
  • Partner with enterprise IT, cybersecurity, and network teams to ensure secure and reliable connectivity to the cloud.

Governance & Standards

  • Author and maintain reference architectures, naming conventions, development guidelines, and security baselines.
  • Contribute to estimation, SoW inputs, and solution guardrails for partners and vendors.

What we offer

Empowering Projects:
With 500+ clients spanning diverse industries and domains, we provide an exciting opportunity to contribute to groundbreaking projects that leverage cutting-edge technologies. As a team, we engineer digital products that positively impact people’s lives.

Empowering Growth:
We foster a culture of continuous learning and professional development. Our dedication is to provide timely and comprehensive assistance for every consultant through our dedicated Learning & Development team, ensuring their continuous growth and success.

DE&I Matters:
At GlobalLogic, we deeply value and embrace
diversity
. We are dedicated to providing
equal
opportunities for all individuals, fostering an
inclusive
and empowering work environment.

Career Development:
Our corporate culture places a strong emphasis on career development, offering abundant opportunities for growth. Regular interactions with our teams ensure their engagement, motivation, and recognition. We empower our team members to pursue their career goals with confidence and enthusiasm.

Comprehensive Benefits:
In addition to equitable compensation, we provide a comprehensive benefits package that prioritizes the overall well-being of our consultants. We genuinely care about their health and strive to create a positive work environment.

Flexible Opportunities:
At GlobalLogic, we prioritize work-life balance by offering flexible opportunities tailored to your lifestyle. Explore relocation and rotation options for diverse cultural and professional experiences in different countries with our company.

About GlobalLogic
GlobalLogic, a Hitachi Group Company, is a trusted digital engineering partner to the world’s largest and most forward-thinking companies. Since 2000, we’ve been at the forefront of the digital revolution – helping create some of the most innovative and widely used digital products and experiences. Today we continue to collaborate with clients in transforming businesses and redefining industries through intelligent products, platforms, and services.

This is a saved copy of a posting published elsewhere. Postings get taken down without notice — check the employer's site before applying. mentors.coach is not the hiring party.

663 more openings in this category and country

Senior Backend Engineer - BookingsSumUp · Poland

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