Senior Software Engineer, Golang - Payments Platform

SumUp’s Payments Tribe develops tools that make transactions easier for small businesses. The team in Sofia, Bulgaria, is searching for a Junior Backend Engineer with experience in Golang to help build and maintain these payment solutions. What you will do Collaborate with engineers to develop and maintain backend services using Golang Contribute to new features that support payment processing for users worldwide Assist in improving the reliability and usability of payment systems Role impact This position supports SumUp’s mission to simplify payments for small businesses and enhance the experience for users globally.

Role overview SumUp is hiring a Software Engineer with solid experience in Golang to join the team in Sofia, Bulgaria. This position centers on building and maintaining online payment solutions that help businesses worldwide process transactions reliably. What you will do Design, develop, and maintain payment services using Golang Collaborate with engineering, product, and design teams Enhance existing systems to improve performance and reliability Implement new features that support user experience and system efficiency Team culture SumUp engineers work together across disciplines to deliver payment products for a global audience. The team values practical approaches and prioritizes solutions that make a real difference for users.

Join Us at SumUp!At SumUp, we empower businesses to effortlessly receive payments, swiftly process orders, and sell online with complete financial control. We develop essential tools that enable businesses to flourish and enhance customer experiences. It's our passion!About the Payments TribeThe Payments Tribe is integral to SumUp, handling payment processing for over 4 million small businesses in 37 markets. Our analytics function within the Processing product family is crucial for supporting product and engineering teams in identifying successes, challenges, and growth opportunities. While we currently have extensive datasets and a robust analytical foundation, our goal is to distill this complexity into clear, actionable insights that facilitate informed decision-making. This role is pivotal in fostering a resilient data culture within one of SumUp’s most vital domains.Your ResponsibilitiesRevamp and simplify key Tableau dashboards to enable non-expert stakeholders to independently assess performance and understand underlying reasons.Define and refine KPI structures to ensure metrics are presented clearly and sequentially for immediate comprehension.Establish a regular insights cadence, providing updates that interpret changes, implications, and recommended actions.Create scalable dashboard templates and self-service patterns to ensure consistent, reliable reporting as the team expands.Develop deep domain expertise in Payments Processing to proactively identify risks, opportunities, and strategic recommendations that influence product priorities.

Join SumUp as a Backend Engineer specializing in Go within our Payments Experience team. In this role, you will be instrumental in building and optimizing backend services that power our payment solutions. You will collaborate with cross-functional teams to enhance user experience and ensure seamless transactions.

At SumUp, we champion the everyday heroes—those with the courage and determination to pursue their passions and realize their dreams.We place small business owners at the center of our mission, crafting powerful and user-friendly financial solutions designed to empower them in managing their businesses. With a founder's mentality and a collaborative, 'team-first' spirit, our diverse teams across Europe, South America, and the United States unite to ensure that small business owners can thrive in their endeavors.About the TeamThe Payments Reporting team is integral to SumUp’s financial infrastructure, developing systems that millions of merchants depend on daily to reconcile, report, and make sense of their finances. We are currently on an exciting journey to build a reporting platform that accommodates both external integrators and internal teams at scale, delivering functionalities from file-based exports to real-time API reporting. This role has emerged due to our ambitious growth outpacing the capacity of our current team of three backend engineers, and we need someone who can take significant ownership of complex backend tasks, allowing the team to accelerate critical architectural improvements.What You Will DoDevelop and maintain backend reporting features, including Payout Reports, Payment Reports, Fee Invoices, and Transaction Reports.Design and manage Reporting APIs (like Transaction History and Payout History) that cater to both external integrators and internal stakeholders.Lead the migration of core payments functionality from legacy systems, modernizing the infrastructure that supports our reporting platform.Ensure the operational health of reporting services through effective monitoring, incident response, and performance optimization.Actively engage in planning and refinement sessions, providing technical assessments and effort estimations.Mentor junior engineers through code reviews, collaborative sessions, and knowledge sharing.

Join Our Team at Kaizen Gaming!At Kaizen Gaming, the driving force behind Betano, we proudly stand as one of the largest GameTech companies globally, with operations in over 20 markets. Our mission is to harness cutting-edge technology to deliver exceptional entertainment experiences to our millions of satisfied customers.Our diverse workforce boasts more than 2,700 talented individuals from over 40 nationalities, spanning three continents. We are thrilled to be recognized among the Best Workplaces in Europe and certified as a Great Place to Work across all our offices. Here, every day is an opportunity for growth and innovation. Are you ready to Press Play on Your Potential?The RoleDesign, build, and maintain efficient, reusable, and reliable code.Develop interfaces between components of heterogeneous subsystems in a high-volume, transaction-oriented production environment.Ensure optimal performance, quality, and responsiveness of applications.Identify bottlenecks and bugs, devising effective solutions to complex challenges.Technology StackOur services primarily utilize C# / ASP.NET, with newer applications developed in .NET Core. The front-end employs Vue.js for new projects, while legacy systems use server-rendered (Razor) views alongside jQuery and Knockout.js. For data storage, we predominantly use MS SQL Server, supplemented by Redis and ElasticSearch when appropriate. RabbitMQ serves as our preferred message broker, and we rely on Gitlab for version control and CI, complemented by the Atlassian suite for ticketing and documentation.What You’ll BringA minimum of 1 year of development experience with C# / ASP.NET / MVC (full framework or .NET Core).A foundational understanding of web technologies, including HTTP.Experience with data access through databases and APIs.Familiarity with unit testing is an advantage.Perks of Working with Us Hybrid working model. Onboarding support from a dedicated buddy. Competitive salary and bonus structure.‍ Comprehensive private health insurance for you and your family. Monthly meal allowance. Access to a multi-sport card. Additional vacation days.⭐ A developmental 360° feedback framework. Unlimited access to Udemy and ongoing training opportunities.

Mirantis seeks a Senior Software Engineer in Sofia with deep experience in Golang. This role centers on building and maintaining scalable software that meets client needs and supports business efficiency. Key responsibilities Design, develop, and support software solutions using Golang Collaborate with colleagues from various disciplines to deliver dependable, high-quality products Contribute to projects aimed at improving processes and serving client requirements What helps people thrive here Strong problem-solving skills and a drive to tackle complex technical challenges A commitment to writing clean, maintainable code Effective collaboration and communication with cross-functional teams

Join Us in Empowering Wealth CreationAt trading212, we are redefining the landscape of trading and investing by crafting innovative products that resonate with users. Our commitment to excellence and rapid execution has been pivotal to our growth.Currently, we proudly support over 4.5 million clients, managing more than €30 billion in assets—an impressive reflection of the trust and scale we’ve achieved in just a few years.Your Role and ResponsibilitiesTake a comprehensive approach to problem-solving, integrating business challenges, service architecture, and the technological landscape into your solutions.Lead the full software development lifecycle (SDLC), from requirements gathering and design through coding, testing, deployment, and monitoring. You will own your code, ensuring it remains robust and optimized for enhancements when opportunities arise.Design for performance, scalability, and resilience, ensuring your code operates flawlessly in a demanding environment where downtime, latency, and data loss are unacceptable.Collaborate within small, autonomous teams with rapid release cycles, leveraging agile methodologies to maintain high velocity while preserving necessary processes.Engage in continuous learning and knowledge sharing within the team, as our growth is contingent on the company’s collective evolution and constructive feedback. What We Expect from YouA solid understanding of common communication protocols, with comfort in using HTTP, WebSockets, and AMQP, alongside the ability to discern appropriate application contexts.Experience with at least one widely-used web framework, regardless of programming language. Our technology-agnostic platform allows engineers to choose the most suitable language for specific tasks, balancing cutting-edge solutions with proven technologies.A strong grasp of RDBMS concepts, including indexing, transactions, isolation levels, and locking mechanisms, with the skills necessary to design high-performance databases.

Join our talented team at devexperts as a Backend Engineer, where you'll play a pivotal role in developing cutting-edge software solutions. Your expertise in backend technologies will help us enhance our products and provide exceptional service to our clients.

Welcome to Kaizen Gaming!At Kaizen Gaming, the driving force behind Betano, we stand as one of the leading GameTech companies globally, operating across 19 dynamic markets. Our commitment is to harness the latest technological advancements, delivering unparalleled experiences to millions of customers who rely on us for their entertainment.With a vibrant team of over 2,700 Kaizeners from more than 40 nationalities across three continents, we embrace diversity and innovation.Proudly recognized among the Best Workplaces in Europe and certified as a Great Place to Work, we promise that every day here is unique and filled with potential. Are you ready to Press Play on your career?About the Role:As a Lead Principal Backend Engineer, you will be pivotal in designing and evolving high-performance, scalable backend systems. We seek a technical expert who excels in leadership and mentorship, guiding engineers at all levels. Your expertise will drive the development of our robust software solutions while collaborating with cross-functional teams to achieve excellence.Your Responsibilities Include:Architecting & Innovating: Partner with our agile team to create scalable, secure, and high-performing backend systems that power our innovative solutions.Code Craftsmanship: Write clean and efficient code that serves as the backbone of our technology stack.Mentorship: Inspire and mentor fellow tech leaders, fostering skill development and the adoption of best practices.Performance Optimization: Spearhead initiatives to identify and enhance system performance, ensuring seamless user experiences.Integration Collaboration: Work closely with cross-functional teams to guarantee smooth system integration.Tech Trendsetter: Stay ahead of technological trends, applying emerging technologies to augment our capabilities and disrupt the industry.Best Practices Advocate: Collaborate with Principal Engineers to establish company-wide best practices and foundational software development processes.Strategic Vision: Define and concentrate on the technical roadmap, aligning it with the company's long-term goals beyond immediate business needs.

Experian is looking for a Junior Data Engineer to join the data engineering team in Sofia. This position supports the design and construction of data pipelines, helping to maintain smooth and reliable data flow across multiple platforms. Role overview As a Junior Data Engineer, daily work involves collaborating with data scientists and analysts. The goal is to understand their requirements and contribute to solutions that support informed, data-driven decisions. What you will do Assist in building and maintaining data pipelines Help ensure data is accessible and flows efficiently between systems Work closely with team members to support analytics and reporting needs Collaboration This role provides the opportunity to learn from experienced engineers and partner with analytics professionals to deliver practical data solutions.

Join Accedia as a Junior Data Engineer and immerse yourself in a dynamic and innovative environment where collaboration and continuous learning are at the forefront. This is an exciting opportunity for individuals who are passionate about data engineering and eager to enhance their skills.What You Can Expect:Be part of a supportive team working on projects for international clients.Contribute meaningfully to team objectives by designing and implementing robust data processing systems, data pipelines, and engaging data visualization solutions.Engage in performance analysis and enhance data reliability and quality.Communicate effectively with your team and clients regarding tasks, requirements, challenges, and queries.Embrace learning opportunities through technology exploration, participating in knowledge-sharing initiatives, and mentoring junior team members.Craft complex SQL queries, scripts, and stored procedures.Develop tailored client reports and refine existing ones proactively to enhance operational efficiency and in response to client requests.Diagnose and resolve issues within existing reports and data by conducting thorough analyses of SQL and reporting outputs.

Join Experian as a Junior Analytics Engineer and embark on a journey to transform data into actionable insights. In this role, you will collaborate with cross-functional teams to analyze data and support decision-making processes. Ideal candidates will possess strong analytical skills, a passion for data, and a desire to grow in the field of analytics.

Join our dynamic team at Accedia as a Junior Data Engineer! We're seeking an enthusiastic individual who is keen to learn, excels in a collaborative environment, and is driven to advance their skills and share knowledge.What You Can Expect: Collaborate in a supportive atmosphere serving international clients.Receive mentorship and guidance from experienced software developers.Contribute to team objectives by engaging in tasks that involve designing and implementing data processing systems, data pipelines, and data visualization solutions.Communicate actively with your mentor, team members, and clients regarding tasks, requirements, and any issues that arise.Expand your skill set through learning new technologies, attending technical and soft skills training, and pursuing professional certifications.Write complex queries and develop database scripts and stored procedures.Create and modify client-specific reports to enhance operational efficiency and respond to customer requests.Analyze SQL and reports to troubleshoot and resolve existing report and data issues.

Join the Global Bank tribe at SumUp, where we are developing the essential infrastructure and core services that empower our merchants with digital bank accounts. Our vision is to be the foremost banking partner for small merchants worldwide, delivering a seamless, straightforward, and affordable banking experience tailored to their unique needs.As a member of the Global Bank tribe, you will play a pivotal role in building SumUp's digital banking ecosystem. Collaborate within a diverse, autonomous, and cross-functional team that brings product ideas from concept to reality. Embrace the opportunity to work with talented colleagues from 32 different nationalities spread across cities like Cologne, Berlin, São Paulo, Sofia, London, and Vilnius, all driven by a shared commitment to ownership, purpose, and supporting small businesses in thriving.As a Senior Backend Engineer, you will take charge of enhancing and maintaining a high-throughput banking ecosystem for our merchants within the Global Bank Tribe. Your contributions will be instrumental in architecting and evolving our global banking platform, ensuring high availability, scalability, and observability across various regions. If you're eager to gain hands-on experience in building products for business accounts, card payments, and transfers across Europe and Latin America for SumUp's Global Bank, we invite you to embark on this exciting journey with us!

Join Our Mission to Empower Wealth BuildingAt trading212, we are revolutionizing the trading and investing landscape by crafting innovative products that resonate with our users.We champion a culture of excellence and agility, driving our success in a rapidly evolving market.Currently, we proudly serve over 4.5 million clients, managing more than €30 billion in assets—a true testament to the trust we have established in just a few years.Your RoleDesign and implement solutions with a comprehensive understanding of business challenges, our service architecture, and the relevant technologies and infrastructure.Be involved in every phase of the software development lifecycle (SDLC)—from gathering requirements and designing implementation to coding, testing, deploying, and monitoring. You will take full ownership of your code and ensure its continuous improvement.Develop robust solutions focused on performance, scalability, and resilience—your code will operate in a high-stakes environment where downtime, latency, and data loss are unacceptable.Collaborate within small, autonomous teams that operate on short release cycles. We value agile methodologies and a balanced approach to processes that avoid chaos without compromising speed.Engage in knowledge sharing and continuous learning with colleagues. As our company evolves, so must we, and constructive feedback is one of our strongest tools for growth. QualificationsProven experience in developing services within a microservice architecture, having contributed to a highly scalable and performant system comprising over 200 microservices.Strong understanding of common communication protocols. You should be adept at utilizing HTTP/WebSockets and AMQP, with the ability to choose the appropriate protocol based on the context.Familiarity with at least one widely-used web framework, regardless of programming language. Our language-agnostic system empowers engineers to select the most suitable language for specific tasks. We strive for a harmonious balance between cutting-edge technologies and proven solutions.A comprehensive understanding of system performance, scalability, and security best practices.

Join the Global Bank tribe where we are revolutionizing the banking infrastructure for merchants. Our mission is to empower small merchants worldwide with a digital business account that simplifies their banking needs, making us the go-to banking partner for them.As a Senior Backend Engineer, you will play a pivotal role in transitioning from fragmented regional systems to a unified global infrastructure, enabling millions of merchants to access seamless banking services tailored to their needs.Your expertise will be crucial in designing and developing a fully distributed, event-driven system that is resilient and compliant across multiple regions.In this role, you will primarily work with Kotlin while having the opportunity to engage with Elixir and Golang. We embrace Extreme Programming methodologies, focusing on small iterations, daily deliveries, and prioritizing technical design quality and deep problem-solving.Our technology stack includes Kotlin, Golang, Elixir, Java, AWS, Kafka, PostgreSQL, and Kubernetes, leveraged by observability tools such as Prometheus, Grafana, and Honeycomb. Additionally, we utilize AI-assisted development tools including Cursor and GitHub Copilot.

Join our dynamic team at Accedia as a Junior QA Engineer! We seek a passionate individual eager to learn, collaborate, and advance their career in a supportive environment.What You Can Expect:Engage in diverse projects for international clients, ensuring quality across various domains and technologies.Contribute to the entire software development lifecycle by developing new features, supporting existing ones, troubleshooting issues, participating in the testing process, and preparing documentation.Work closely with a cross-functional team, analyzing technical requirements, proposing architectural and system design solutions, estimating effort, and planning tasks.Communicate actively with team members and clients about tasks, requirements, issues, and open questions.Expand your knowledge by learning new technologies, participating in knowledge-sharing initiatives, and pursuing professional certifications.

Join Our Mission to Empower Wealth BuildingAt Trading 212, we are redefining the trading and investing landscape by developing outstanding products that resonate with our users. Our commitment to fostering a culture of excellence and agility is pivotal to our growth.In recent years, we have expanded our client base significantly, growing twenty-fold to over 4 million clients, while the assets managed have increased to over €4 billion.Your RoleDesign and implement scalable, self-healing infrastructure and applications in both public and private cloud settings.Utilize IaaS automation tools such as Terraform, AWS CloudFormation, and Ansible.Facilitate the migration of systems from on-premise setups to AWS/GCP.Manage operational and security alerts and incidents.Enhance monitoring systems for infrastructure, applications, and security.Drive continuous performance improvements and troubleshoot critical components.Engage in knowledge-sharing with colleagues to foster collective growth and provide constructive feedback.This position requires shift work, including public holidays.