Backend Engineer, Data

Sumup

SumUp’s Point-of-Sale (POS) solution empowers cafes, shops, bars, hair salons, and other businesses to operate efficiently and grow. It offers a wide range of features, including product catalogs, inventory management, business analytics, compliance support, and loyalty tools. As a Backend Engineer in the Orders & Sales or Catalog Platform team, you will build the engine powering core infrastructure for over 4 million businesses worldwide. Whether you are architecting global sales APIs or scaling item management systems, your work is central to the SumUp ecosystem. The Orders & Sales team builds high-performance APIs and receipt engines that unify transaction and sales data, utilizing an AI-native mindset and extreme collaboration. Meanwhile, the Catalog Platform team owns the backend for item management, variants, categories, and taxes, focusing on high-stakes reliability and core POS infrastructure scaling. WHAT YOU’LL DO * Develop and evolve high-performance backend services and APIs using Kotlin and Spring Boot. * Design and maintain robust data schemas and event-driven integrations (Kafka) to handle complex transaction and catalog data at scale. * Write clean, well-tested, production-grade code and contribute meaningfully to code reviews and team rituals. * Collaborate with mobile and product teams to ship end-to-end features with a focus on performance and data consistency. * Engage in daily pair programming to solve complex concurrency challenges and maintain high architectural standards. * Take full ownership of the development lifecycle, including managing CI/CD pipelines and monitoring service health in production. * Actively use and experiment with AI coding agents to automate repetitive tasks and increase shipping velocity. * Refactor and migrate mission-critical domain logic to centralize and simplify the "Sales" and "Catalog" experiences across the ecosystem. YOU’LL BE GREAT FOR THIS ROLE IF * You have 3+ years of experience in backend engineering with the JVM stack (preferably Kotlin and Spring Boot). * You have a solid understanding of software design patterns, data modeling, and fundamental system architecture principles. * You are comfortable working with Kafka, Postgres, and AWS in a production environment at scale. * You enjoy and actively seek out collaboration and daily pair programming as a primary way of working. * You are an "AI-native" engineer, open to using agents and tools to optimize your coding process. * You have experience with, or a strong interest in, distributed and fault-tolerant systems. * You are a fast learner who values quality, detail, and effective time management. * You are fluent in English and can communicate clearly with both technical and non-technical stakeholders. NICE TO HAVE * Experience with Kubernetes and cloud-native observability/monitoring tools. * Knowledge of different programming paradigms (Functional vs. OOP). * Familiarity with high-scale applications involving many concurrent processes. * A desire to share knowledge with the wider engineering community. Why you should join SumUp 🌎 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 🌈 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 you can be used to attend conferences and/or advancing your career through further education 💶 A corporate pension scheme where we match up to 20% of your contributions 🏖️ Generous time off: enjoy 28 days of paid leave plus public holidays and special leave days 🚵🏾‍♂️ Numerous other benefits such as Urban Sports Club subsidy, Kita placement assistance, subsidised office lunches 🌴 Break4me: 1-month sabbatical after 3 years of service 🔗 Referral Bonus: earn additional rewards by referring talented individuals to join the SumUp team About SumUp We believe in the everyday hero. Small business owners are at the heart of all we do, so we're creating tools that help them run their businesses. With a founder’s mentality and a 'team-first’ attitude, our diverse teams across Europe, South America and the United States work together to ensure that the small business owners we partner with can be successful doing what they love.  SumUp is an Equal Employment Opportunity employer that proudly pursues and hires a diverse workforce. SumUp does not make hiring or employment decisions on the basis of race, colour, religion or religious belief, ethnic or national origin, nationality, sex, gender, gender identity, sexual orientation, disability, age or any other basis protected by applicable laws or prohibited by company policy. SumUp also strives for a healthy and safe workplace and strictly prohibits harassment of any kind. SumUp will not accept unsolicited resumes from any source other than directly from a candidate. 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. 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.

Reddit

Reddit is a community of communities. It’s built on shared interests, passion, and trust, and is home to the most open and authentic conversations on the internet. Every day, Reddit users submit, vote, and comment on the topics they care most about. With 100,000+ active communities and approximately 126 million daily active unique visitors, Reddit is one of the internet’s largest sources of information. For more information, visit www.redditinc.com. Reddit is continuing to grow our teams with the best talent. This role is completely remote friendly within the United States. If you happen to live close to one of our physical office locations (San Francisco, Los Angeles, New York City & Chicago) our doors are open for you to come into the office as often as you'd like The Moderation organization’s mission lies at the core of Reddit's success as a platform: we build features that enable moderators to create and grow meaningful, destination communities. Moderators are a key pillar of Reddit’s success, and act as community leaders and tastemakers, ensuring there’s something on Reddit for everyone. This team drives several core product metrics for the entire Reddit ecosystem. This is a high impact role where you will drive related technical & product strategy, operations, architecture, and execution for one of the largest sites in the world. What You’ll Do: * Work cross-functionally with product, design, and other engineering counterparts to execute on product and business strategy and build novel products and features that our users will love. * Contribute to the full development cycle: technical design, development, test, experimentation, analysis, and launch. You’ll be reviewing code and design docs, giving feedback on product specs and mocks. * Continuously learn and improve your technical and non-technical abilities. Who You Might Be: * 2-5 years of software development industry experience in an enterprise environment  * BS degree in Computer Science, a similar technical field of study or equivalent practical experience. * Proficiency with one or more general-purpose programming languages; Go or Python (required), Rust, Ruby. * Experienced with GraphQL, REST, HTTP, Thrift or gRPC basics, and the ability to design and implement maintainable APIs. * Strong organizational skills, the ability to prioritize tasks and keep projects on schedule. * Entrepreneurial spirit. You are self-directed, innovative, and biased towards action in fast-paced environments. You love to build new things and thrive in ambiguity and even failure. * Excellent communication skills. You collaborate effectively with teams in a fully remote environment and discuss complex topics with technical and non-technical audiences. Benefits: * Comprehensive Healthcare Benefits and Income Replacement Programs * 401k with Employer Match * Global Benefit programs that fit your lifestyle, from workspace to professional development to caregiving support * Family Planning Support * Gender-Affirming Care * Mental Health & Coaching Benefits * Flexible Vacation & Paid Volunteer Time Off * Generous Paid Parental Leave    #LI-SP1 Pay Transparency: This job posting may span more than one career level. In addition to base salary, this job is eligible to receive equity in the form of restricted stock units, and depending on the position offered, it may also be eligible to receive a commission. Additionally, Reddit offers a wide range of benefits to U.S.-based employees, including medical, dental, and vision insurance, 401(k) program with employer match, generous time off for vacation, and parental leave. To learn more, please visit https://www.redditinc.com/careers/. To provide greater transparency to candidates, we share base salary ranges for all US-based job postings regardless of state. We set standard base pay ranges for all roles based on function, level, and country location, benchmarked against similar stage growth companies. Final offer amounts are determined by multiple factors including, skills, depth of work experience and relevant licenses/credentials, and may vary from the amounts listed below. The base salary range for this position is: $164,200—$229,900 USD In select roles and locations, the interviews will be recorded, transcribed and summarized by artificial intelligence (AI). You will have the opportunity to opt out of recording, transcription and summarization prior to any scheduled interviews. During the interview, we will collect the following categories of personal information: Identifiers, Professional and Employment-Related Information, Sensory Information (audio/video recording), and any other categories of personal information you choose to share with us. We will use this information to evaluate your application for employment or an independent contractor role, as applicable.  We will not sell your personal information or disclose it to any third party for their marketing purposes.  We will delete any recording of your interview promptly after making a hiring decision.  For more information about how we will handle your personal information, including our retention of it, please refer to our Candidate Privacy Policy for Potential Employees and Contractors. Reddit is proud to be an equal opportunity employer, and is committed to building a workforce representative of the diverse communities we serve.  Reddit is committed to providing reasonable accommodations for qualified individuals with disabilities and disabled veterans in our job application procedures. If, due to a disability, you need an accommodation during the interview process, please let your recruiter know.

Gitlab

GitLab is the intelligent orchestration platform for DevSecOps. GitLab enables organizations to increase developer productivity, improve operational efficiency, reduce security and compliance risk, and accelerate digital transformation. More than 50 million registered users and more than 50% of the Fortune 100* trust GitLab to ship better, more secure software faster. The same principles built into our products are reflected in how our team works: we embrace AI as a core productivity multiplier, with all team members expected to incorporate AI into their daily workflows to drive efficiency, innovation, and impact. GitLab is where careers accelerate, innovation flourishes, and every voice is valued. Our high-performance culture is driven by our values and continuous knowledge exchange, enabling our team members to reach their full potential while collaborating with industry leaders to solve complex problems. Co-create the future with us as we build technology that transforms how the world develops software. *Fortune 500® is a registered trademark of Fortune Media IP Limited, used under license. Claim based on GitLab data. Fortune 100 refers to the top 20% ranked companies in the 2025 Fortune 500 list, published in June 2025. Fortune and Fortune Media IP Limited are not affiliated with, and do not endorse products or services of GitLab. AN OVERVIEW OF THIS ROLE As a Backend Engineer on the GitLab Agent Observability team, you'll go beyond using AI tools and help define how we design, build systems that allow AI agents to interact with the full software delivery lifecycle, way beyond pure code creation.  In this role you’ll contribute to the development of complex features and help establish architectural patterns both for how to interact with AI Agents across GitLab and how the resulting AI contributions manifest across GitLab. You’ll collaborate closely with engineers across the Agent Foundations stage and adjacent teams within AI engineering. This is a high-visibility area of the product at the intersection of GitLab's core platform and its AI strategy.                WHAT YOU'LL DO * Develop, ship, and maintain features and improvements for Agent Observability and Interactions across both the GitLab monolith backend and the AI gateway in a secure, well-tested, and performant way. * Collaborate with Product Management, UX, frontend, backend, and AI specialists to refine requirements and deliver high-quality, iterative product enhancements. * Design, implement, and review GraphQL, REST APIs and related backend logic, ensuring reliability, scalability, and clear contracts with frontend clients. * Improve and extend automated testing, including RSpec and other frameworks, to strengthen quality, reliability, and developer feedback loops. * Share standards, patterns, and learnings with other engineers, raising the bar for responsible AI integration and evidence-driven engineering across the team. * Participate in Tier 2 on-call rotations to troubleshoot production issues, contribute to root cause analysis, and enhance observability and resiliency WHAT YOU'LL BRING * Experience building and maintaining production applications with Ruby on Rails, including work with background jobs, APIs, and data models. * Comfortable working across the stack in a mature codebase. Familiarity with Python backends and/or Vue frontends a plus. * Proficiency in designing or extending REST and/or GraphQL APIs with attention to scalability, maintainability, and backward compatibility. * Strong practical experience working with AI tooling on a daily basis. Experience designing and shipping AI-powered backend features and integrations is a plus. * SQL skills and familiarity with relational databases such as PostgreSQL, including writing efficient queries and understanding data modeling. * Openness to learning, collaborating in an async-first, distributed team, and applying transferable skills from related technologies or domains. * Clear written and verbal communication skills, including writing technical proposals and documentation, and collaborating effectively in a remote, asynchronous, cross-functional environment. ABOUT THE TEAM Agent Observability is a new functional team within the Agent Execution group. The team itself will initially consist of three engineers across AMER and EMEA timezones. The whole Agent Execution group consists of 8+ engineers. Beyond the Agent Observability team, Agent Execution consists of further teams focussed on agent tools and executing agents on GitLab’s runners. We’re partnering with teams both within the AI space as well as all over GitLab to ensure that the Duo Agent Platform can become the backbone of many AI features at GitLab.  HOW GITLAB SUPPORTS FULL-TIME EMPLOYEES * Benefits to support your health, finances, and well-being * Flexible Paid Time Off  * Team Member Resource Groups * Equity Compensation & Employee Stock Purchase Plan * Growth and Development Fund * Parental Leave  Please note that we welcome interest from candidates with varying levels of experience; many successful candidates do not meet every single requirement. Additionally, studies have shown that people from underrepresented groups are less likely to apply to a job unless they meet every single qualification. If you're excited about this role, please apply and allow our recruiters to assess your application. ---------------------------------------------------------------------------------------------------------------------------------- Country Hiring Guidelines: GitLab hires new team members in countries around the world. All of our roles are remote, however some roles may carry specific location-based eligibility requirements. Our Talent Acquisition team can help answer any questions about location after starting the recruiting process.   Privacy Policy: Please review our Recruitment Privacy Policy. Your privacy is important to us. GitLab is proud to be an equal opportunity workplace and is an affirmative action employer. GitLab’s policies and practices relating to recruitment, employment, career development and advancement, promotion, and retirement are based solely on merit, regardless of race, color, religion, ancestry, sex (including pregnancy, lactation, sexual orientation, gender identity, or gender expression), national origin, age, citizenship, marital status, mental or physical disability, genetic information (including family medical history), discharge status from the military, protected veteran status (which includes disabled veterans, recently separated veterans, active duty wartime or campaign badge veterans, and Armed Forces service medal veterans), or any other basis protected by law. GitLab will not tolerate discrimination or harassment based on any of these characteristics. See also GitLab’s EEO Policy and EEO is the Law. If you have a disability or special need that requires accommodation, please let us know during the recruiting process.