April 24, 2026
Senior Backend Engineer - JVM (Java/Kotlin) & AWS
Senior • Remote
65,000 - 70,000 EUR
Berlin, BE, Germany
At Adsquare, our mission is driven by two core pillars:
Passion – Solving complex challenges with great people, technology, and data
Niche – Location Intelligence for Programmatic Advertising
Our core values are at the heart of everything we do:
Drive: We turn ambition into action
Resilience: We adapt, persevere, and grow stronger
No BS: We value honesty, transparency, and clear communication
Humble: We choose modesty over vanity and let results speak for themselves
Moral Compass: We do the right thing with fairness, integrity, and respect
We are looking for candidates who not only bring strong technical expertise but also embody these values in their everyday work.
Your Mission
As a Senior Backend Engineer at Adsquare, you will take ownership of designing and operating high-scale distributed systems that power our core data products.
Your primary mission is to build reliable, high-throughput backend services on the JVM that process and serve large volumes of location intelligence data in real time.
You will work in a highly autonomous, cross-functional team and are expected to proactively identify problems, propose solutions, and drive them into production.
In this role, you will:
Design and evolve distributed backend systems with a strong focus on scalability, performance, and reliability
Own services end-to-end: from architecture decisions to production operations
Build and operate cloud-native systems on AWS
Collaborate closely with Product and Data teams to deliver impactful features
Continuously improve system design, engineering practices, and team effectiveness
Your Profile
We are looking for a senior-level engineer with strong backend and cloud experience, comfortable owning complex production systems.
Must have
4–5+ years of experience building backend systems in production environments
Strong expertise in Java or other JVM-based languages (Kotlin, Scala) and the Spring ecosystem
Proven experience designing and operating distributed systems under real-world load
Hands-on experience with AWS and cloud-native architectures
Strong understanding of concurrency, data consistency, and system reliability
Experience with PostgreSQL or other relational databases in high-throughput environments
Ability to debug and optimize production systems (performance, memory, latency)
Proactive mindset: you identify problems, take ownership, and drive solutions independently
We especially value candidates who:
Have worked on high-volume data or high-throughput systems
Understand trade-offs between architectural approaches (sync vs async, etc.)
Are comfortable making decisions in ambiguous environments
What You Will Do
Maintain and evolve existing partner integrations, ensuring reliability and scalability
Design and build new integrations for large-scale data delivery
Contribute to migrating services toward a cloud-native AWS architecture
Monitor system health, troubleshoot production issues, and improve stability
Desired Background
We are particularly interested in candidates with experience in:
Data-intensive or high-throughput backend systems
Cloud-based architectures (especially AWS)
API-driven or partner integration systems
Monolith-to-distributed or cloud-native transformations
Your Opportunities
In this role, you will have real influence over the technical direction of our systems.
We operate with a high level of ownership: engineers are expected to make decisions, propose improvements, and drive execution from idea to production.
You will:
Shape system architecture and key technical decisions
Own services end-to-end and evolve them over time
Contribute to scaling our systems and data processing capabilities
Work in an environment that values initiative and accountability
Recruiting Process
Our hiring process is transparent, focused, and respectful of your time:
Intro & Values Conversation – Getting to know each other, discussing experience, and aligning expectations
Technical Interviews – Backend fundamentals and system design discussions
Final Step – Team meeting followed by decision and offer
A reference check will be conducted at the final stage.
Our Tech Stack
Our backend stack is centered around the JVM ecosystem and AWS:
Core technologies:
Java (11+) and Kotlin
Spring / Spring Boot
AWS (S3, SQS/SNS, Lambda, etc.)
PostgreSQL
Also used in our environment:
Terraform (Infrastructure as Code)
MongoDB
Kubernetes
Data tools (Athena, Glue, Batch, Step Functions)
We do not expect experience with all of these technologies, but you should be comfortable working in modern cloud and data-intensive environments.
Similar jobs you might like
Technology
AgileEngine
Backend Engineer
Senior
Remote
Krakow, Poland
5,600 - 7,400 USD
🏢 Summary: Senior Backend Engineer role to architect and build the core systems of a next-generation AdTech platform, focusing on high-throughput, low-latency services for campaign delivery, targeting, and attribution. The position involves defining system architecture from the ground up using Python, Django, Kubernetes, and AWS in a distributed, scalable environment. Engineers will drive technical direction, optimize performance, and provide leadership in a fast-paced, product-driven setting. 🗂️ Requirements: 5+ years of software development experience building scalable backend systems, Strong knowledge of algorithms, data structures, networking, and databases, Proven experience designing and scaling distributed systems, Experience with backend programming languages (e.g. Java, .NET, Python, Node.js), Ability to design high-throughput, low-latency systems, Experience with system architecture and technical decision-making, Availability to work until 1pm EST, Upper-intermediate English level 📃 Skills: Python, Django, Kubernetes, AWS, PostgreSQL, Java, .NET, Node.js, ETL, OpenRTB, Prebid.js, GoogleAdManager, AmazonUAM, DSP, SSP 🏢 Description: ID68432 AgileEngine is an Inc. 5000 company that creates award-winning software for Fortune 500 brands and trailblazing startups across 17+ industries. We rank among the leaders in areas like application development and AI/ML, and our people-first culture has earned us multiple Best Place to Work awards. Why join us If you're looking for a place to grow, make an impact, and work with people who care, we'd love to meet you! :) About the role We are looking for a Senior Backend Engineer to architect and build the core systems of a next-generation AdTech platform that embeds products directly into visual experiences. You will design high-throughput, low-latency services for campaign delivery, targeting, attribution, and partner integrations using Python, Django, Kubernetes, and AWS. This is an early-stage initiative where senior engineers define the technical direction and system architecture from the ground up. What you will do Architect, build, and evolve core systems for the Ads platform; Design APIs and services supporting campaign management, targeting, delivery, attribution, and reporting; Build and optimize high-throughput, low-latency systems processing large volumes of events and data; Own critical systems end-to-end, including design, implementation, deployment, monitoring, and ongoing improvements; Drive architectural decisions and establish patterns that support scalability, reliability, and developer productivity; Collaborate closely with product, data, and partner teams to translate business requirements into robust technical solutions; Provide technical leadership through design reviews, system discussions, and mentoring other engineers; Contribute to engineering best practices, documentation, and long-term platform vision; Participate in hiring and help grow a strong, high-performing team. Must haves 5 years of software development experience building scalable systems using backend programming languages/frameworks (e.g. Java , .NET , Python , Node.js , etc); Deep understanding of computer science fundamentals, including algorithms, data structures, networking, and databases; Proven experience designing and scaling distributed systems with a focus on performance, observability, and fault tolerance; Strong architectural instincts and the ability to make high-leverage technical decisions that impact multiple teams and systems; Demonstrated ability to influence and mentor senior engineers, guide teams through ambiguity, and elevate engineering practices across the board; Exceptional ownership mindset; Availability to work till 1pm EST (till 8 pm Kyiv time) ; Excellent communication and cross-functional collaboration skills; Comfortable operating in a fast-paced, high-autonomy, product-driven environment; Experience with e-commerce and catalog management is preferred; Familiarity with Python , Django , Kubernetes , PostgreSQL , and AWS is strongly preferred, but deep expertise in analogous systems and a willingness to learn are welcome; Upper-intermediate English level. Nice to haves Strong experience with complex ETL flows and high-throughput systems is highly preferred; Experience with AdTech (This may include experience with DSPs, SSPs, ad exchanges, affiliate programs, Prebid.js, Prebid Server, Google Ad Manager, Amazon UAM/TAM, OpenRTB, identity and addressability solutions, as well as ad operations workflows.) The benefits of joining us Professional growth: Accelerate your professional journey with mentorship, TechTalks, and personalized growth roadmaps Competitive compensation: We match your ever-growing skills, talent, and contributions with competitive USD-based compensation and budgets for education, fitness, and team activities A selection of exciting projects: Join projects with modern solutions development and top-tier clients that include Fortune 500 enterprises and leading product brands Flextime: Tailor your schedule for an optimal work-life balance, by having the options of working from home and going to the office – whatever makes you the happiest and most productive. Meet Our Recruitment Process Asynchronous stage – An automated, self-paced track that helps us move faster and give you quicker feedback: Short online form to confirm basic requirements 30–60 minute skills assessment via Codility – a platform founded in Poland that helps us provide quicker feedback and streamline this stage of the process. 5-minute introduction video Synchronous stage – Live interviews Technical interview with our engineering team (scheduled at your convenience) Final interview with your future teammates If it’s a match — you’ll get an offer!
Technology
emagine Polska
Senior AI Software Engineer – Backend
Senior
Remote
Lisbon, Portugal
🏢 Summary: Senior AI Software Engineer – Backend role focused on designing, building, and scaling production-grade AI backend services, including LLM integrations, RAG pipelines, and distributed cloud-native systems. The position emphasizes reliable, observable, and secure AI solutions deployed in AWS using modern backend and infrastructure practices. You will work in an Agile environment delivering scalable APIs, microservices, and AI-driven workflows for enterprise use cases. 🗂️ Requirements: Bachelor’s degree in Computer Science, Software Engineering, Data Engineering, or related field, 6+ years backend or software engineering experience, Hands-on experience delivering AI-enabled or data-intensive backend solutions, Proficiency in at least one backend language: Python, Java, Go, Kotlin, C#, or TypeScript, Strong experience building REST APIs, microservices, and distributed systems, Experience with Python backend frameworks such as FastAPI and async programming, Experience integrating LLMs or cloud AI services with orchestration layers, Knowledge of RAG, vector search, and semantic retrieval concepts, Experience with SQL and NoSQL databases, Experience with AWS cloud services and cloud-native architectures, Experience with Terraform or infrastructure-as-code tools, Experience with Git and Agile/Scrum methodologies, Knowledge of testing, monitoring, logging, and AI evaluation practices 📃 Skills: Python, Java, Go, Kotlin, C#, TypeScript, FastAPI, REST, Microservices, LLM, RAG, Vector, SQL, NoSQL, AWS, Terraform, Git, Scrum, Kubernetes, Docker, CI/CD, Async, Serverless, Containers 🏢 Description: YOUR CONTRIBUTION Our culture is agile and collaborative, and we genuinely believe our people are some of the best with which you’ll ever work. We are looking for a skilled and passionate Senior AI Software Engineer – Backend to join our Centre of Excellence and the SWE team to design, build and scale production-grade AI services, intelligent workflows, and backend platforms that create measurable business value. YOUR “DAY-TO-DAY”: Design, develop and operate production-grade AI backend services, APIs, and event-driven components with strong focus on scalability, reliability, latency, and cost efficiency. Build and integrate capabilities based on LLMs and other AI services, including prompt orchestration, structured outputs, tool calling, and workflow automation. Develop retrieval and knowledge integration patterns such as RAG, vector search, and metadata-driven content pipelines for enterprise use cases. Participate and support Agile methods and frameworks by taking part in planning events, daily stand-ups, code reviews, and technical discussions. Collaborate closely with product, platform, frontend, DevOps, security, and data stakeholders as a valued member of a self-managing, cross-functional SWE team. Implement robust observability, evaluation and guardrails for AI solutions, including logging, tracing, monitoring, feedback loops and incident troubleshooting. Manage and optimize scalable distributed systems on the Cloud, using secure-by-design and infrastructure-as-code practices. Develop automated tests and evaluation suites to validate backend logic, model behavior, regression scenarios, and non-functional requirements. Translate product and business needs into reliable technical designs, reusable services, and maintainable integration patterns. Continuously improve architecture, developer experience, and engineering standards by contributing to best practices, reviews, and technical mentorship within the Backend community. BACKGROUND AND QUALIFICATIONS: Bachelor's Degree or higher in Computer Science, Software Engineering, Data Engineering, or related field, with appropriate professional experience. Proven work experience as a Backend Engineer or Software Engineer for 6+ years, with hands-on delivery of AI-enabled or data-intensive backend solutions. Strong experience with Agile delivery frameworks such as Scrum and modern source code management practices using Git. Knowledge of AI engineering patterns such as agentic workflows, semantic caching, prompt/version management, and human-in-the-loop controls. Strong proficiency in one or more backend languages such as Python, Java, Go, Kotlin, C#, or TypeScript, with production experience building APIs and services. Solid experience designing and operating backend services, microservices, and distributed systems, including RESTful APIs, asynchronous processing, and messaging patterns. Hands-on experience with Python-based AI/backend frameworks and service development patterns, such as FastAPI, async programming, data validation, and structured outputs. Experience integrating foundation model or cloud AI services and building reliable orchestration layers for prompts, tools, and model interactions. Good knowledge of data access patterns and storage technologies, including SQL and NoSQL databases, caching, and vector databases or semantic retrieval concepts. Experience with AWS cloud services and cloud-native engineering practices, including serverless, containers, observability, and infrastructure automation. Experience with Terraform or other infrastructure-as-code tooling. Knowledge of AI solution quality practices, including testing strategies, evaluation, monitoring, security, privacy, and responsible-use guardrails. Knowledgeable about software architecture, design patterns, logging, monitoring, and performance optimization. Excellent analytical and time management skills, strong teamwork mindset, and a pragmatic problem-solving attitude. Passionate about software engineering, continuous learning, and the practical adoption of emerging AI technologies. ADDITIONAL EXPERIENCE PREFERRED OR HELPFUL: Experience with cloud AI platforms and managed model services, preferably in AWS environments. Experience with Kubernetes, Docker containers, and CI/CD pipelines for deploying and operating AI-enabled services. Experience with product and collaboration tools such as Jira and Confluence. Summary: Senior AI Software Engineer – Backend Role in a nutshell: A senior backend engineer focused on building and scaling production-grade AI services — think LLM integrations, RAG pipelines, agentic workflows, and cloud infrastructure — within a collaborative, cross-functional team. Experience needed: 6+ years in backend/software engineering, with hands-on AI or data-intensive delivery. Must-have tech: Python (FastAPI, async), REST APIs, microservices, Terraform, AWS, SQL/NoSQL/vector databases, Git, Agile/Scrum. Nice to have: Kubernetes, Docker, CI/CD, Terraform, Jira/Confluence. Key soft skills: Strong communicator, team player, pragmatic problem-solver, passionate about AI and continuous learning. Degree: Computer Science, Software Engineering, or related field. The right candidate is someone who bridges solid backend engineering fundamentals with practical AI delivery experience — not just a data scientist or ML researcher, but an engineer who ships reliable, observable AI products in production.
Technology
AgileEngine
Backend Engineer (AdTech)
Senior
Remote
Krakow, Poland
5,600 - 7,400 USD
🏢 Summary: Senior Backend Engineer role focused on architecting and building the core systems of a next-generation AdTech platform, designing high-throughput, low-latency services for campaign delivery, targeting, and attribution. The position involves defining system architecture from scratch, scaling distributed systems, and providing technical leadership in a fast-paced environment. Strong experience with scalable backend development and AdTech ecosystems is required. 🗂️ Requirements: 5+ years of experience building scalable backend systems, Experience in AdTech (DSPs, SSPs, ad exchanges, Prebid, Google Ad Manager, OpenRTB, etc.), Strong knowledge of algorithms, data structures, networking, and databases, Proven experience designing and scaling distributed systems, Experience with backend programming languages (Java, .NET, Python, Node.js), Ability to design high-throughput, low-latency systems, Upper-intermediate English level, Availability to work until 1pm EST, Experience mentoring engineers and driving architectural decisions 📃 Skills: Python, Django, Kubernetes, AWS, PostgreSQL, Java, .NET, Node.js, OpenRTB, Prebid.js, Prebid, GoogleAdManager, AmazonUAM, AmazonTAM, ETL 🏢 Description: ID52365 AgileEngine is an Inc. 5000 company that creates award-winning software for Fortune 500 brands and trailblazing startups across 17+ industries. We rank among the leaders in areas like application development and AI/ML, and our people-first culture has earned us multiple Best Place to Work awards. Why join us If you're looking for a place to grow, make an impact, and work with people who care, we'd love to meet you! :) About the role We are looking for a Senior Backend Engineer to architect and build the core systems of a next-generation AdTech platform that embeds products directly into visual experiences. You will design high-throughput, low-latency services for campaign delivery, targeting, attribution, and partner integrations using Python, Django, Kubernetes, and AWS. This is an early-stage initiative where senior engineers define the technical direction and system architecture from the ground up. What you will do Architect, build, and evolve core systems for the Ads platform; Design APIs and services supporting campaign management, targeting, delivery, attribution, and reporting; Build and optimize high-throughput, low-latency systems processing large volumes of events and data; Own critical systems end-to-end, including design, implementation, deployment, monitoring, and ongoing improvements; Drive architectural decisions and establish patterns that support scalability, reliability, and developer productivity; Collaborate closely with product, data, and partner teams to translate business requirements into robust technical solutions; Provide technical leadership through design reviews, system discussions, and mentoring other engineers; Contribute to engineering best practices, documentation, and long-term platform vision; Participate in hiring and help grow a strong, high-performing team. Must haves 5 years of software development experience building scalable systems (backend programming languages/frameworks, e.g. Java , .NET , Python , Node.js etc); Experience with AdTech (This may include experience with DSPs, SSPs, ad exchanges, affiliate programs, Prebid.js, Prebid Server, Google Ad Manager, Amazon UAM/TAM, OpenRTB, identity and addressability solutions, as well as ad operations workflows); Deep understanding of computer science fundamentals (algorithms, data structures, networking, databases); Proven experience designing and scaling distributed systems focusing on performance, observability, and fault tolerance; Strong architectural instincts and the ability to make high-leverage technical decisions that impact multiple teams and systems; Demonstrated ability to influence and mentor senior engineers, guide teams through ambiguity, and elevate engineering practices across the board; Exceptional ownership mindset — you drive initiatives forward, raise the bar, and deliver lasting impact; Excellent communication and cross-functional collaboration skills; Availability to work till 1pm EST (till 8 pm Kyiv time) ; Comfortable operating in a fast-paced, high-autonomy, product-driven environment; Experience with e-commerce and catalog management is preferred; Familiarity with Python , Django , Kubernetes , PostgreSQL , and AWS is strongly preferred, but deep expertise in analogous systems and a willingness to learn are welcome; Upper-intermediate English level. Nice to haves Strong experience with complex ETL flows and high-throughput systems is highly preferred. The benefits of joining us Professional growth Accelerate your professional journey with mentorship, TechTalks, and personalized growth roadmaps Competitive compensation We match your ever-growing skills, talent, and contributions with competitive USD-based compensation and budgets for education, fitness, and team activities A selection of exciting projects Join projects with modern solutions development and top-tier clients that include Fortune 500 enterprises and leading product brands Flextime Tailor your schedule for an optimal work-life balance, by having the options of working from home and going to the office – whatever makes you the happiest and most productive. Meet Our Recruitment Process Asynchronous stage – An automated, self-paced track that helps us move faster and give you quicker feedback: Short online form to confirm basic requirements 30–60 minute skills assessment via Codility – a platform founded in Poland that helps us provide quicker feedback and streamline this stage of the process. 5-minute introduction video Synchronous stage – Live interviews Technical interview with our engineering team (scheduled at your convenience) Final interview with your future teammates If it’s a match — you’ll get an offer!
Technology
iTeamly
Staff / Senior Java Developer
Senior
Remote
Krakow, Poland
19,500 - 29,500 PLN
🏢 Summary: Senior Backend Engineer role focused on designing and developing scalable, reliable backend services using Java. The position involves working in a cross-functional team to build high-performance systems, improve architecture, and support CI/CD and production environments. 🗂️ Requirements: 5+ years Backend Engineering experience, Strong Java proficiency, Solid knowledge of databases and SQL, Experience with RESTful APIs, Experience with microservices architecture, Experience with high-load systems, Experience with Docker and Kubernetes, Experience with AWS or GCP, Knowledge of CI/CD pipelines, Understanding of Agile practices 📃 Skills: Java, SQL, REST, Microservices, Docker, Kubernetes, AWS, GCP, CI/CD, Golang, Python 🏢 Description: We are looking for a Senior Backend Engineer with strong Java experience to help us design and develop scalable solutions. You will work in a cross-functional team, building reliable services and contributing to the continuous improvement of our systems. This role is ideal for someone who enjoys solving complex problems and driving technical excellence. 💼 Responsibilities: Design, develop, and maintain backend features and services. Collaborate with teams to define requirements and integrate systems. Ensure performance, scalability, and reliability of applications. Contribute to CI/CD processes and support production systems. Write clear documentation and share knowledge within the team. ✅ Requirements: 5+ years of experience as a Backend Engineer, with strong Java skills (Golang/Python is a plus). Solid understanding of databases and SQL. Experience with RESTful API design, microservices, and high-load systems. Familiarity with Docker, Kubernetes, and cloud environments (AWS/GCP). Knowledge of CI/CD pipelines and Agile practices. Strong problem-solving and communication skills. 🎁 We offer: Stable employment in a fast-growing company. Flexible and remote-friendly working model. Health and wellbeing benefits. Learning and development opportunities. Modern equipment and comfortable work environment.
Technology
ITDS
Senior Node.js Backend Engineer – AWS & Microservices
Senior
Remote
Warsaw, Poland
21,000 - 27,300 PLN
🏢 Summary: Fully remote Senior Node.js Backend Engineer role focused on building and scaling cloud-native microservices in a serverless AWS environment. The position involves designing high-performance REST APIs, provisioning infrastructure with Terraform, and optimizing distributed systems for scalability and resilience. You will contribute to CI/CD pipelines and ensure robust, production-grade backend services. 🗂️ Requirements: 4+ years of professional experience in Node.js server-side development, 2+ years of experience in system and data integration, transformation, and validation, Strong experience designing and deploying REST APIs, Hands-on experience with Terraform for AWS infrastructure provisioning, Practical experience with AWS services: Lambda, SQS, CloudWatch, S3, Deep understanding of distributed systems, scalability, and failure handling, Experience with CI/CD pipelines and GitHub Actions, Proficiency with shell scripting and Linux command-line tools 📃 Skills: Node.js, AWS, Lambda, SQS, CloudWatch, S3, Terraform, REST, CICD, GitHubActions, Shell, Linux, DistributedSystems, DynamoDB, DocumentDB, Streaming 🏢 Description: Ignite innovation at the forefront of cloud-native backend development — shape scalable microservices for dynamic digital ecosystems. Fully-remote opportunity! As a Senior Node.js Backend Engineer , you will be working for our client, a leading technology-driven organization dedicated to building resilient distributed systems that power tomorrow's digital experiences. You will contribute to designing and implementing high-performance microservices on AWS, enhancing system robustness, scalability, and flexibility. Join us and be part of pioneering solutions that redefine industry standards and accelerate your career growth. Your main responsibilities: Develop and maintain REST-like APIs and backend services using Node.js in a serverless AWS environment Design, implement, and optimize infrastructure-as-code configurations with Terraform for AWS services such as Lambda, SQS, CloudWatch, and S3 Integrate complex data streams, transform, validate, and analyze data within distributed systems Collaborate with cross-functional teams to ensure system robustness, scalability, and failure resilience Contribute to CI/CD pipelines utilizing GitHub Actions, and enforce best practices in version control Troubleshoot and resolve operational issues within AWS infrastructure and backend services Maintain comprehensive documentation and ensure high-quality code standards You're ideal for this role if you have: At least 4 years of professional experience in Node.js server-side development 2+ years of experience in system/data integration, transformation, and validation Deep understanding of distributed systems, including scalability, elasticity, replication, and failure handling Strong experience designing and deploying REST-like APIs Hands-on experience with Terraform for AWS infrastructure provisioning Practical knowledge of serverless AWS services: Lambda, SQS, CloudWatch, S3 Solid grasp of GitHub tool suite, CICD pipelines, and shell scripting Good command of Linux command line tools Excellent communication skills in English Problem-solving mentality with a focus on business impact It is a strong plus if you have: Experience with DynamoDB, DocumentDB, and Streaming services Language Required for the role: Fluent English Eligibility for the role: Only candidates with an existing legal right to work in the European Union will be considered for this role. We offer you At ITDS , you will work on innovative and impactful technology projects for international companies across multiple industries in Europe and beyond. We create an environment for ambitious, driven professionals who want to grow, deliver value, and build their careers in modern IT and digital transformation. Our offer includes: Stable and long-term cooperation with attractive conditions Opportunities to develop your technical expertise across various industries and technologies The chance to work on high-impact, strategic IT and digital transformation projects A clear career path and the opportunity to grow quickly by contributing to diverse client initiatives over time International environment , knowledge sharing, social events, and training opportunities Access to an attractive medical package Access to the Multisport program Access to learning platforms such as Pluralsight Flexible working hours and remote work options #MAKEYourCareerBETTER Interested? Apply now and include your CV (preferably in English) along with a statement confirming your consent to the processing and storage of your personal data. # 8942
Technology
DataArt
Senior Backend Engineer with Java
Senior
Remote
Wroclaw, Poland
16,000 - 19,000 PLN
🏢 Summary: Senior Backend Engineer role focused on defining the technical direction and architecture of a domain within a borderless financial platform. The position involves designing scalable microservices, driving architectural decisions, and leading a small backend team in a distributed environment. The role emphasizes reliability, security, and high‑volume transaction processing in a cloud-based ecosystem. 🗂️ Requirements: 4-7 years backend engineering experience, Proficiency in Go, Experience with Java 21 or modern Java, Experience designing microservices with clear contracts, Experience with caching strategies including TTL and invalidation, Experience with event-driven or asynchronous architectures, Experience with structured logging, metrics, and alerting, Experience with AWS services, Experience with relational and non-relational databases, Experience with Spring Boot or similar frameworks, Experience reviewing code and architectural decisions, Availability to work in GMT+5:30 timezone 📃 Skills: Java, Go, Spring, JDBI, PostgreSQL, CockroachDB, DynamoDB, Redis, SQS, SNS, Kafka, AWS, EKS, ALB, RDS, S3, Kong, Datadog, Quickwit, JWT, RBAC, TLS, Docker, ArgoCD, GitHub, Microservices, Kafka, CDC 🏢 Description: Project overview This project focuses on developing a borderless financial platform that supports international banking flows, payments, account management and regulatory compliant operations. The product handles sensitive data and high volume transactions while prioritising reliability and security. Team You will work in a distributed environment with backend engineers, a product manager and platform specialists. The role involves leading a sub team of three to five engineers, conducting design reviews, ensuring code quality standards and supporting collaborative decision making. Position overview We are looking for a Senior Backend Engineer who will define the technical direction of a backend domain and drive architectural decisions. You will design microservices, create scalable solutions, guide a small engineering group and collaborate closely with product specialists to shape the delivery roadmap. We are looking for a person willing to work in the time zone: GMT+5:30. Technology stack Java 21, Go, Spring Boot, JDBI, custom workflow engines, PostgreSQL, CockroachDB, DynamoDB, Redis, SQS, SNS, Kafka, AWS EKS ALB RDS S3 Secrets Manager, Kong API Gateway, Datadog, Quickwit, JWT RBAC TLS request and response encryption VAPT, GitHub Actions, Docker, ArgoCD, microservices, event driven architecture, saga and orchestration patterns, CDC pipelines, maker checker workflows Responsibilities Plan and design backend microservices with clear boundaries and contracts Develop solutions for domains such as onboarding, payments, transaction orchestration or platform components Break complex epics into actionable tasks with clear acceptance criteria Review designs from other engineers to ensure scalability and fault tolerance Drive technical decisions including caching layers, asynchronous processing strategies, database choices and API versioning Evaluate build versus buy options for integrations and services Collaborate with a product manager to align on scope and prioritisation Lead a sub team of backend engineers and support their professional growth Support incident response, root cause analysis and long term improvements Monitor service performance using logging, metrics and tracing tools Requirements Professional backend engineering experience from 4-7 years Experience with Go (tooling & CLIs) Experience designing microservices with well-defined contracts and boundaries Experience with Java 21 or modern Java versions Experience with caching strategy design, including TTL and invalidation approaches Experience working with asynchronous processing, event-driven architecture, or queue-based workflows Experience using structured logging, metrics, and alerting to debug production systems Experience in making build versus buy decisions with clear trade-off analysis Experience reviewing code and identifying architectural or contract issues Experience with AWS-based services Experience working with relational and non-relational databases such as PostgreSQL or DynamoDB Experience writing backend services using Spring Boot or similar frameworks Nice to have Experience with financial or payments related systems Experience with KYC or AML flows Experience with workflow or orchestration engines Experience with platform wide pattern creation or reusable service design Experience with data encryption practices and security audits Experience with CockroachDB or high availability distributed databases What We Offer: Vacation days : Up to 26 business days per year. 10 illness/special days off per year (fully paid, no medical papers needed) for all contract types Health and life insurance (Luxmed) MyBenefit platform with Multisport option Internal psychological support service English language classes from the first working day Access to external learning platforms : O’Reilly, LinkedIn Learning, Udemy, and a wide catalog of diverse internal training Flexible workplace : work from the office, from home, or choose a hybrid option Tech Skills Mentoring Program Opportunities to develop as a public speaker, mentor, or technical interviewer Fully paid idle (bench) when not involved in a project Certification reimbursement (AWS, GCP, Microsoft, etc.)
Technology
AgileEngine
Software Engineer
Senior
Remote
Krakow, Poland
5,600 - 7,400 USD
🏢 Summary: Senior Backend Engineer role focused on designing and building scalable serverless middleware services for digital ordering, payments, loyalty, and third-party integrations on a major consumer platform using AWS and Node.js/TypeScript. The position emphasizes event-driven architecture, infrastructure as code, secure authentication, and active use of AI-assisted development tools. It involves API development at scale, cloud-native deployments, and collaboration on high-quality, secure backend systems. 🗂️ Requirements: 4+ years of backend development experience, Experience building and operating RESTful and/or GraphQL APIs at scale, Proficiency in JavaScript or TypeScript, Experience with serverless architectures on AWS (Lambda, API Gateway, DynamoDB, SQS/SNS), Experience with CI/CD pipelines and Git-based source control workflows, Familiarity with Infrastructure as Code (Terraform or CloudFormation), Understanding of event-driven architecture, webhooks, async messaging, pub/sub, Experience integrating with third-party and vendor APIs, Strong debugging and production incident management skills, Upper-intermediate English level 📃 Skills: JavaScript, TypeScript, Node.js, AWS, Lambda, API Gateway, DynamoDB, SQS, SNS, Terraform, CloudFormation, Git, GitHub, Azure, REST, GraphQL, Cognito, OAuth2, OpenID, Datadog, Dynatrace, CloudWatch, Akamai, CloudFront, CI/CD 🏢 Description: ID72455 AgileEngine is an Inc. 5000 company that creates award-winning software for Fortune 500 brands and trailblazing startups across 17+ industries. We rank among the leaders in areas like application development and AI/ML, and our people-first culture has earned us multiple Best Place to Work awards. Why join us If you're looking for a place to grow, make an impact, and work with people who care, we'd love to meet you! :) About the role We are looking for a Senior Backend Engineer to design and build scalable middleware services powering digital ordering, payments, loyalty, and third-party integrations across a major consumer platform. You will develop serverless applications using AWS Lambda and API Gateway, build Node.js/TypeScript microservices, design event-driven architectures with SQS/SNS, and implement infrastructure as code with Terraform. The role includes active use of AI-assisted development tools as a core part of the daily engineering workflow. What you will do Develop serverless applications using AWS Lambda and API Gateway; Build and maintain Node.js/TypeScript microservices; Design event-driven architectures using SQS/SNS; Build infrastructure as code using Terraform; Leverage AI-assisted development tools (GitHub Copilot, Claude, and similar) as a core part of daily engineering work — from code generation and refactoring to test coverage and documentation. Champion AI tooling adoption across the team; Create integrations with delivery providers and payment platforms; Collaborate with business stakeholders and product teams to understand functional and technical requirements; translate those into scalable, maintainable architecture and implementation plans; Conduct constructive code reviews and provide technical design guidance to peers and junior engineers, raising the overall quality and consistency of team output; Enforce data governance, security policies, and compliance standards throughout the software development lifecycle; Implement secure authentication and identity flows using Amazon Cognito. Must haves 4+ years of backend development experience ; Demonstrated experience building and operating RESTful and/or GraphQL APIs at scale; Strong proficiency in one or more of: JavaScript/TypeScript (Node.js, Java, or C#) ; Experience with serverless architectures on AWS ( Lambda , API Gateway , DynamoDB , SQS/SNS ); Demonstrated experience building and operating RESTful and/or GraphQL APIs at scale; Experience with CI/CD pipelines and source control workflows (Git, GitHub Actions, Azure DevOps); Familiarity with Infrastructure as Code ( Terraform or CloudFormation); Solid understanding of integration patterns: event-driven architecture, webhooks, async messaging, and pub/sub; Experience integrating with third-party platforms and vendor APIs (e.g., delivery aggregators, POS systems, loyalty platforms, or similar ecosystem partners); Ability to translate ambiguous business requirements into clear technical specifications; Collaborative mindset with a willingness to give and receive candid code review feedback; Strong debugging, root-cause analysis, and production incident management skills. Upper-intermediate English level. Nice to haves DoorDash, Uber Eats, or similar delivery integrations; Payment platform integrations; Restaurant, retail, or QSR experience; Amazon Cognito expertise; Experience with multi-region AWS deployments and global traffic management (Akamai, CloudFront); Familiarity with identity and authentication patterns: OAuth 2.0, OpenID Connect, AWS Cognito; Hands-on experience with observability platforms (Dynatrace, Datadog, CloudWatch); Experience prompting, fine-tuning, or orchestrating LLMs/AI agents as part of a software delivery workflow; Experience in QSR, retail, or e-commerce domains; AWS Certified Developer – Associate or higher; Exposure to React Native or cross-platform mobile app integration patterns. The benefits of joining us Professional growth: Accelerate your professional journey with mentorship, TechTalks, and personalized growth roadmaps Competitive compensation: We match your ever-growing skills, talent, and contributions with competitive USD-based compensation and budgets for education, fitness, and team activities A selection of exciting projects: Join projects with modern solutions development and top-tier clients that include Fortune 500 enterprises and leading product brands Flextime: Tailor your schedule for an optimal work-life balance, by having the options of working from home and going to the office – whatever makes you the happiest and most productive. Meet Our Recruitment Process Asynchronous stage – An automated, self-paced track that helps us move faster and give you quicker feedback: Short online form to confirm basic requirements 30–60 minute skills assessment via Codility – a platform founded in Poland that helps us provide quicker feedback and streamline this stage of the process. 5-minute introduction video Synchronous stage – Live interviews Technical interview with our engineering team (scheduled at your convenience) Final interview with your future teammates If it’s a match — you’ll get an offer!
Technology
Awareson Sp. z o.o.
Senior Backend Developer with Python
Senior
Remote
Warsaw, Poland
170 - 210 PLN
🏢 Summary: Senior Backend Engineer role focused on designing and scaling a high-throughput, event-driven platform. The position centers on building and optimizing large-scale event processing services and APIs in distributed systems. It involves solving complex scalability and reliability challenges in a massive-scale environment. 🗂️ Requirements: Senior-level experience in backend development, Strong Python expertise, Experience scaling message queue systems, Experience with distributed systems and microservices architecture, Proven track record building high-throughput backend services, Experience designing scalable and fault-tolerant systems, Ability to implement and optimize APIs 📃 Skills: Python, Azure, ServiceBus, StorageQueues, EventHubs, Microservices, DistributedSystems, APIs, EventDriven, EventSourcing, Streaming, Observability, Monitoring 🏢 Description: Location: Remote Type: Full-time Level: Senior Duration: 4 months Start: ASAP We are looking for an experienced Senior Backend Engineer to join a team responsible for building and scaling a high-throughput, event-driven platform operating at massive scale. Your primary focus will be the event processing backbone — designing, developing, and optimizing services that handle large volumes of messages reliably and efficiently. You will work closely with architects and other senior engineers to implement APIs that expose data and support advanced triage and processing workflows. This role is ideal for someone who enjoys solving hard scalability problems , working with distributed systems, and building resilient backend services that operate under real-world load. Responsibilities Design and build backend services responsible for large-scale event processing Optimize and scale message-based systems to handle high throughput and reliability requirements Implement APIs defined by system architects to expose data and collect processing results Collaborate with cross-functional teams to improve platform performance and resilience Contribute to architectural decisions around scalability, fault tolerance, and observability Core Skills Strong experience with Python as a primary backend language Deep expertise in scaling message queue systems (e.g. Azure Service Bus, Storage Queues, Event Hubs or similar) Solid understanding of microservices architecture and distributed systems Proven experience building high-throughput, resilient backend services Strong problem-solving skills and ability to work with complex systems Highly Desirable Experience with event-driven or event sourcing architectures Background in data processing frameworks or streaming systems Experience building platforms related to observability, monitoring, or large-scale event management Familiarity with designing systems for fault tolerance and graceful degradation What we offer Work on technically challenging systems operating at very large scale High level of autonomy and real influence on system architecture Collaboration with experienced engineers in a mature engineering environment Competitive compensation and flexible working model Project with strong technical ownership
Technology
Starbridge
Senior Backend Software Engineer | Java/Kotlin | EMEA/LATAM
Senior
Remote
Warsaw, Poland
8,000 - 11,500 USD
🏢 Summary: Senior Backend Engineer role focused on building and scaling backend systems for an AI-driven product that transforms complex government data into actionable insights. The position involves designing data ingestion, processing pipelines, and distributed infrastructure from scratch, with full ownership from architecture to production. You will work closely with a small senior team to deliver scalable, production-ready systems. 🗂️ Requirements: 6+ years of Backend Engineering experience, Experience in JVM ecosystem, Experience in product companies (B2B SaaS preferred), Experience designing and owning backend systems in production, Strong knowledge of system design and scalability, Experience building asynchronous or distributed systems, Ability to make and justify technical decisions, Fluency in English, Valid work authorization in Europe or LATAM 📃 Skills: Kotlin, Java, JVM, SQL, GCP, Messaging, Queues, DistributedSystems, SystemDesign, DataPipelines, LLMs, AI 🏢 Description: About the role We’re looking for a Senior Backend Engineer to join our early team and help build our product from zero to one. You’ll work on a product that helps companies navigate complex government data, from contracts and grants to market signals and turn it into actionable insights using AI. On the backend side, this means working on data ingestion, processing, and the infrastructure that powers search and AI-driven workflows at scale. You’ll collaborate closely with a small, senior team and have real ownership, from shaping solutions to shipping them to production and improving them over time. You might be a fit if you: Must have: 6+ years of experience as a Backend Engineer, preferably in the JVM ecosystem (we use Kotlin on the backend) Experience working in product companies (B2B SaaS preferred) with direct impact on shipped features Experience working in small companies or startups would be a strong advantage Experience designing and owning backend systems in production (from initial design to deployment and ongoing improvements) Strong understanding of system design, including scalability, failure handling, and trade-offs Experience building asynchronous or distributed systems (e.g. messaging, queues, event-driven systems) Ability to make and justify technical decisions, not just implement given solutions Fluency in written and spoken English Nice to have: Experience with large-scale data processing, scraping, or data pipelines Experience working with LLMs / AI-related systems Experience with GCP or similar cloud environments How We Work Build Bridges to Help Customers Win - We pride ourselves on being obsessively customer-centric. Shooting Star Speed - We move with extreme speed. We value momentum, decisiveness, and the ability to accelerate when it matters. Fun Is a Feature - Fun is a Feature means we intentionally design Starbridge to be an energizing place to do hard work. Joy, humor, and camaraderie make great teams faster, sharper, and more resilient. In the Arena - We believe the best ideas come from living close to the work, feeling the friction, hearing the nuance, and experiencing the details firsthand. Benefits include: Competitive salary + early-stage equity Unlimited PTO Regular off-sites (NYC + global locations) Interview Process We move fast — really fast. Getting back to someone today beats tomorrow, and our interview process reflects that mindset. Please keep us posted on your timeline so we can move quickly and speed things up where needed. After submitting your application, the team reviews your CV and statement of exceptional work. If your application passes this stage, you will be invited to a 30-minute interview during which a member of our team will make sure you're a good fit for the role. You will have the opportunity ask questions and learn more about the role as well. We'll then send you a programming challenge that consists of two parts: LeetCode and SQL. Beyond that step, you will enter the main process, which consists of three interviews: System design exercise hands-on. Live coding in Java/Kotlin. Product thinking and past work. All interviews will be conducted via Google Meet. Eligibility to Work in Europe or LATAM: Candidates must hold valid authorization to work in the country where they will be based. At this time, we are unable to offer visa sponsorship or assist with work permit applications.
Technology
ITDS
Senior Java Spring Boot Backend Developer – Cloud and Microservices
Senior
Hybrid
Krakow, Poland
24,150 - 30,450 PLN
🏢 Summary: Senior Java Spring Boot Backend Developer role focused on building and modernizing a cloud-native Messaging Delivery Platform in the financial sector. The position involves developing scalable microservices, APIs, and containerized applications deployed on AWS using Kubernetes. It combines hands-on backend engineering with DevOps practices in an Agile environment. 🗂️ Requirements: Minimum 6 years of Java development experience, Strong hands-on experience with Spring Boot, Experience with microservices architecture, Practical experience with Kubernetes, Experience with AWS cloud environment, Experience with CI/CD tools (Jenkins, GitHub, Maven, Groovy), Strong knowledge of API design (REST, Swagger, OpenAPI, JSON), Experience with OAuth2 and API Gateway solutions, Experience working in Agile (Scrum, TDD), Legal right to work in the European Union 📃 Skills: Java, Spring, SpringBoot, Microservices, Kubernetes, AWS, Jenkins, GitHub, Maven, Groovy, REST, Swagger, OpenAPI, JSON, OAuth2, Kong, CI/CD, TDD, Scrum 🏢 Description: Unleash innovation at scale — drive the future of cloud-native, microservices architectures! Krakow-based opportunity with hybrid work model (3 remote days per week). As a Senior Java Spring Boot Backend Developer , you will be working for our client in the financial industry, focusing on the Messaging Delivery Platform—centralizing and modernizing message delivery to bank customers across multiple channels. Join a cutting-edge project that shapes the future of client communication through advanced distributed systems and cloud technology. Your main responsibilities: Develop high-quality, scalable backend applications using Java and Spring Boot, ensuring adherence to technical requirements and standards. Collaborate within a multidisciplinary Agile team to design, build, and enhance distributed microservices architectures. Implement and monitor API solutions using Swagger, OpenAPI, REST, and JSON standards, ensuring best practices. Deploy and manage containerized applications on Kubernetes, leveraging AWS cloud infrastructure. Integrate authentication and authorization mechanisms such as OAuth 2 and API Gateway solutions. Write and execute unit tests, contribute to automation testing efforts, and uphold quality benchmarks. Participate in code reviews, challenge implementations to maintain highest quality standards, and promote innovation. Keep abreast of current technologies, tools, and industry best practices, continuously enhancing your expertise. Support and mentor team members to foster a culture of technical excellence and knowledge sharing. You're ideal for this role if you have: Minimum 6 years of experience in Java development within a senior or expert capacity. Strong hands-on expertise with Spring Boot framework and microservices architecture. Practical experience with Kubernetes and Cloud environments, particularly AWS. Proficiency with CI/CD tools such as Jenkins, GitHub, Maven, and Groovy scripting. Deep understanding of API design principles, including Swagger, OpenAPI 3.0, REST, and JSON. Familiarity with authentication protocols like OAuth 2 and API Gateway solutions such as Kong. Robust knowledge of Agile practices, especially TDD and Scrum methodologies. Ability to work fluently in English, with excellent communication skills. It is a strong plus if you have: Certifications or additional experience with AWS services. Knowledge of automation testing frameworks. Experience with messaging systems or middleware. Eligibility for the role: Only candidates with an existing legal right to work in the European Union will be considered for this role. #MAKEYourCareerBETTER Interested? Apply now and include your CV (preferably in English) along with a statement confirming your consent to the processing and storage of your personal data.