Senior Backend Engineer at SumUp | Sofia, Bulgaria

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 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 Our Mission to Empower Wealth BuildingAt Trading 212, we are transforming the landscape of trading and investing. Our innovative products are designed to empower individuals to build their wealth effectively.We believe that a culture rooted in excellence and rapid innovation is essential to our success.With over 4.5 million clients and more than €30 billion in assets under management, we have quickly established a reputation for scale and trust in the financial industry.Your ResponsibilitiesArchitect and implement dynamically scalable, self-healing infrastructure and applications across public and private cloud platforms.Continuously enhance and automate infrastructure designs to boost resilience and scalability.Utilize IaaS automation tools such as Terraform, AWS CloudFormation, and Ansible.Facilitate the migration of environments from on-premise infrastructure to AWS/GCP.Analyze application and infrastructure KPIs, proactively identifying and addressing bottlenecks and potential issues.Design infrastructures that ensure zero downtime.Drive continuous performance improvements and troubleshoot critical components.Engage in knowledge sharing with colleagues to foster growth as the company evolves, valuing honest feedback as a crucial tool for success.Required QualificationsProven expertise in public cloud platforms, specifically AWS and GCP.In-depth understanding of DevOps principles and their practical application in various workflows; experience with CI/CD tools such as GitHub, GitLab, or Jenkins.Hands-on experience with containerization technologies and orchestration systems, including Docker, Kubernetes, EKS/ECS, and Nomad.Solid understanding of Infrastructure as Code practices using tools like Terraform and AWS CloudFormation.Experience in implementing and maintaining configuration management tools such as Puppet and Ansible.Expertise in relational databases including AWS RDS, MySQL/MariaDB/PostgreSQL, and TimescaleDB.Familiarity with messaging services like Amazon MSK, Amazon MQ, Kafka, and RabbitMQ.Strong proficiency in Python and Bash scripting.Preferred QualificationsExperience with on-premise private cloud infrastructure.

About Trading212 Trading212 builds trading and investing products for a global client base. The company serves over 5 million clients and manages more than €30 billion in assets. A focus on excellence and agility shapes both its culture and its rapid growth. Role Overview: HR Specialist This HR Specialist role in Sofia centers on administrative support and coordination across HR processes and company events. The position suits someone with strong organizational skills and an interest in improving the employee experience. Key areas include onboarding, HR administration, event planning, and supporting internal engagement. Main Responsibilities Oversee onboarding and offboarding: create HRIS profiles, arrange first-day logistics, deliver induction presentations, and manage documentation (contracts, background checks, visas, termination orders) to meet international labor law requirements. Handle employment and change letters, respond to employee questions, and keep HRIS records accurate and up to date. Assist with preparing HR reports, data analytics, and dashboards as needed. Support performance review cycles by setting timelines, helping managers, and monitoring progress. Administer employee benefits and coordinate with external partners for effective delivery. Help organize HR initiatives, team-building activities, and company celebrations. Act as a main point of contact for HR policy questions and feedback. Qualifications Minimum 1 year of experience in an HR-related position. Degree in Human Resources, Business Administration, or a related field preferred. Comfort with reporting tools such as Excel or similar software. What Trading212 Offers Challenging projects that foster professional growth. Work alongside a team of skilled, driven, and supportive colleagues. An environment where individual contributions are valued.

Empowering Wealth Building for AllAt trading212, we are redefining the landscape of trading and investing by delivering innovative products that resonate with our users.Our commitment to excellence and agility is paramount to our continued success.With over 5 million clients and €30 billion in assets under management, we have established a robust reputation in a short span.Your Role as a Customer Experience SpecialistWe are on the lookout for a dedicated customer advocate to join our dynamic team. We prioritize hiring individuals who are knowledgeable, approachable, and eager to provide exceptional service.Your role will be pivotal in delivering outstanding customer support to our growing international clientele. You will collaborate with a high-performing team, allowing for significant career development opportunities.Essential Skills and QualificationsFluency in English (C1 level or higher)Customer-centric mindsetStrong time management and multitasking abilitiesDesire for continuous learning and personal growthFlexibility to adapt to a rapidly evolving environmentPreferred QualificationsExperience in customer service rolesFamiliarity with the stock market and fintech sectorProficiency in an additional languageYour ResponsibilitiesEngage with clients in English and BulgarianHandle incoming inquiries through chat and emailAssist clients in navigating our applicationResolve account-related queriesRelay client feedback to enhance serviceWork on a rotating 24/7 shift scheduleWhat We ProvideIn-depth training to familiarize you with our businessOngoing professional development opportunitiesRecognition of your talents and contributionsCompetitive salary packageComprehensive social benefits

Join Us in Our Mission to Empower Wealth BuildingAt trading212, we are redefining the landscape of trading and investing by delivering outstanding products that resonate with our users.Our commitment to fostering a culture of excellence and agility drives our success.Currently, we proudly serve over 4.5 million clients, managing more than €30 billion in assets - a testament to the trust and scale we have achieved in just a few years.Your RoleMake a significant impact on millions of users with every production change you implement.Contribute to our pursuit of technical excellence by developing a frontend monorepo that powers Trading 212’s iOS, Android, Web, and Desktop applications with a focus on efficiency and code reuse.Take ownership of project health; as a product-focused company, maintaining code quality is vital for our longevity.Collaborate within compact, autonomous teams that operate on short release cycles, ensuring agility and high performance without compromising on quality.Engage in mutual learning and knowledge sharing with your colleagues, as we believe in growing together through honest feedback. Essential SkillsProficient in HTML, CSS, and JavaScript.Experience with React/React Native and familiarity with one or more state management libraries.Strong attention to detail.Excellent communication skills. Preferred QualificationsExperience with advanced TypeScript.Currently pursuing or possess a degree in Computer Science. What We OfferOpportunities for rapid personal and professional growth through challenging projects.The chance to make a substantial impact by developing innovative services utilized by millions of investors.Collaborate with a team of intelligent, spirited, and high-achieving colleagues, all focused on a shared vision.A dynamic environment where creativity and ideas are highly valued.Recognition and appreciation for your unique talents and insights.A competitive compensation package.

Our mission is to empower everyone to build wealth.At Trading 212, we are transforming the landscape of trading and investing by developing outstanding products that resonate with our users.Our success stems from cultivating a culture of excellence and agility.Currently, we proudly serve over 4.5 million clients and manage assets exceeding €30 billion, reflecting the scale and trust we have rapidly established.Your ResponsibilitiesAssume ownership of quality assurance tasks, including work estimates, execution, and closure initiatives.Engage in design and requirements reviews to ensure product features are testable and user-friendly.Create and develop both manual and automated test cases to guarantee the quality and reliability of our software solutions.Plan, implement, and perform testing across various product domains, including database, integration, functional, and UI/UX testing.Evaluate test results to pinpoint areas for enhancement and suggest process improvements.Ensure compliance with company testing standards throughout all QA activities.Collaborate in small, autonomous teams with rapid release cycles, leveraging agile methodologies while maintaining the right processes for efficiency. QualificationsMinimum of 2 years of experience in software quality assurance, with a focus on test automation.Proficient understanding of software testing methodologies and industry best practices.Competent programming skills in at least one language (e.g., Python, TypeScript, Java).Advanced knowledge of relational database management systems (RDBMS).Strong analytical and problem-solving capabilities.Excellent command of English and superior communication skills.A genuine passion for quality assurance. Preferred QualificationsBachelor's degree in Computer Science, Information Technology, Mathematics, or a related discipline.Familiarity with API testing tools like Postman or SoapUI.Experience testing microservices and distributed systems.

Our mission is to empower individuals to create wealth.At Trading 212, we are transforming the landscape of trading and investing by developing outstanding products that our users adore.Our dynamic team is composed of highly motivated individuals who pursue excellence and cherish autonomy.With over 4.5 million clients and more than €30 billion in assets under management, our growth and trust in the market speak volumes about our success.We are in search of passionate and experienced Principal Software Engineers to drive innovation and scalability in our systems.

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.

Join Our Mission to Empower Wealth BuildingAt Trading 212, we are revolutionizing the trading and investing landscape by delivering outstanding products that our users adore. Our commitment to fostering a culture of excellence and rapid innovation is pivotal to our success.Currently, we proudly serve over 4.5 million clients, managing assets exceeding €30 billion - a testament to our remarkable growth and the trust we've established in a brief period.Your RoleMake a significant impact on millions of users with each production deployment.Contribute to our technical excellence vision by enhancing our frontend monorepo, which supports Trading 212's iOS, Android, Web, and Desktop applications with an emphasis on efficiency and code reuse.Collaborate closely with the design and backend teams to ensure the highest quality of our products, as effective communication is essential.Take ownership of the project’s health and maintainability, reflecting our commitment as a product-centric company.Required QualificationsProficient in JavaScript with an in-depth understanding of the language.Significant experience with React or React Native, and TypeScript.Strong comprehension of HTTP protocols.Exceptional attention to detail.Excellent communication skills.Preferred QualificationsExperience in a product-focused company.Advanced TypeScript knowledge, including generics, discriminated unions, and conditional types.Familiarity with CI/CD processes.Experience in native mobile app development for either iOS or Android.Expertise in high-end web development and optimizations.Ongoing or completed Computer Science education.Our Technology StackTypeScriptReact NativeReact QueryZustandNxKotlinSwift What We ProvideEngaging challenges that foster professional growth and development.Opportunities to work with cutting-edge technologies in a dynamic environment.

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.

Founded with a clear mission to democratize investing, Trading 212 has evolved into a trusted platform for over 4.5 million clients, managing assets exceeding €30 billion. Our commitment to excellence and rapid innovation fuels our drive to create intuitive, powerful products that empower individuals to grow their wealth. We believe investing should be straightforward, impactful, and accessible to everyone.The RoleAs a Product Designer, you will play a crucial role in defining the user experiences that millions rely on for confident investing. You will be directly involved in designing and implementing features that transform complex financial tools into user-friendly interfaces. Collaborating closely with product managers and engineers, you will rapidly translate ideas into tangible designs.This position is perfect for those with some experience who are eager to develop their design skills, expand their product knowledge, and make a significant impact on users daily.Your ResponsibilitiesDesign and implement key features in our app, ensuring exceptional user experiences.Actively engage in the design process, from initial concepts to detailed UI.Collaborate closely with product managers and engineers to deliver high-quality work swiftly.Present your designs and embrace feedback as a means for ongoing improvement.Commit to continuous growth as a designer, enhancing your skills and knowledge daily.Contribute to maintaining our design system to ensure product consistency.Your QualificationsAt least 2 years of experience in designing impactful digital products.A portfolio demonstrating strong visual design capabilities and attention to detail.Strong communication and teamwork skills.Self-motivated and proactive in driving projects forward.A genuine desire to learn and expand your expertise.Proficiency in Figma.Preferred QualificationsExperience in fintech or industries with strict compliance requirements.Background in developing and maintaining design systems.

At Brandwatch, we are committed to empowering every individual to make a significant impact. Your voice is valued here, and your unique insights contribute to our collective success. As part of our global team, you'll flourish in an environment that fosters curiosity, collaboration, and innovation, while making meaningful contributions to the brands we support.Join us in redefining the future of communication and building authentic connections that matter. Whether you are tackling complex challenges or spearheading bold innovations, your growth is synonymous with our success. Together, we will create the conversations of tomorrow.Empower your impact at Brandwatch. Be seen, be understood, be you.Brandwatch is actively seeking a dedicated member for the Measure team. You will join a cross-functional and autonomous product team responsible for delivering solutions for performance monitoring and analytics across major social media platforms including Facebook, Instagram, Twitter, LinkedIn, TikTok, and YouTube.As a Backend Engineer at Brandwatch, you will work with the latest Long-Term Support (LTS) versions of Java and Spring, interfacing with some of the most influential social networks globally. You will consume and store data from their APIs at scale, creating REST APIs that expose vital social media KPIs to our clients. Additionally, you will design and implement a scalable microservice architecture.

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 Innovative Team as a Senior Backend Software Engineer! The Mobile Fulfilment Systems team at Ocado Group is pioneering state-of-the-art automation solutions for in-store and warehouse online order fulfilment. We harness the power of distributed backend systems, user-friendly mobile applications, and advanced autonomous robots to facilitate rapid, scalable, and cost-efficient order collection. As a key member of our Mobile Fulfilment Systems team, particularly within the In-Store Fulfilment (ISF) division, you'll be involved in designing and developing distributed cloud-based systems, PWA mobile applications, and web technologies aimed at automating the fulfilment of online customer orders at scale. What is In-Store Fulfilment? ISF is a comprehensive cloud-based solution that empowers stores to efficiently fulfil customer orders, enhancing the shopping experience while minimizing operational costs. We are currently operational in over 1,000 stores across 11 countries and 4 continents, handling more than 300,000 customer orders weekly. In Your Role as a Senior Software Engineer, You Will: Design, develop, and maintain large-scale, high-availability distributed systems. Lead technical initiatives from conception through to implementation, fully owning the planning, coordination, design, and execution processes. Ensure solutions consistently meet quality standards by adhering to best practices in testing, code quality, monitoring, and alerting. Contribute to the long-term architectural and product vision. Utilize AI tools, such as Claude Code, Gemini, and GitHub Copilot, to enhance our development processes. Engage in all phases of the software development lifecycle within an agile team framework. Continuously seek to enhance our processes, workflows, and tools. Collaborate closely with business and product partners to translate system requirements into engineering solutions. Participate in our on-call rotation to support production services. Mentor and train both new and existing team members in their professional development.

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.

About the Role mangroup is looking for a DevOps Engineer in Sofia to help improve and maintain our deployment processes. This role works closely with both development and IT operations teams to automate workflows and support the reliability of our applications. What You Will Do Manage infrastructure and deployment pipelines Implement and maintain CI/CD practices Monitor cloud environments for performance and availability Troubleshoot and resolve operational issues Identify and drive improvements to existing systems Location This position is based in Sofia.

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.