Jobs Java

We are looking for a Senior Full Stack Engineer (Java + React) for our partner, a growing software company based in Spain.

Our partner combines product development with client-facing engineering work. They build their own products in the search and AI space while also delivering software solutions for enterprise customers.

As part of an international engineering team, you will work on a live production platform used by real customers, contributing across both backend and frontend development and playing a key role in the evolution of its architecture.

This is a full-time remote contract position with an initial commitment of at least six months and the possibility of long-term extension.

Responsibilities

• Design, develop, and maintain backend services and APIs using Java and Spring Boot.
• Develop and maintain modern frontend applications using React.
• Build and deliver end-to-end features across the backend and frontend.
• Participate in a major platform migration toward a more secure and modern architecture.
• Contribute to architectural and technical design decisions.
• Transform business requirements into scalable technical solutions.
• Improve and refactor existing systems while maintaining production stability.
• Work with AWS infrastructure and cloud-based production environments.
• Collaborate closely with QA and cross-functional teams throughout the development lifecycle.
• Participate in Agile ceremonies and planning activities.
• Use AI-assisted development tools as an integral part of the engineering workflow.

Requirements

Technical Skills

• 6+ years of professional software engineering experience.
• Strong hands-on experience with Java and Spring Boot.
• Strong hands-on experience with React and modern frontend development.
• Strong hands-on experience with AWS and building or deploying production applications in AWS environments.
• Proven experience building and maintaining production-grade APIs and web applications.
• Solid understanding of software architecture, system design, and data modeling.
• Good understanding of frontend architecture, component-based development, and API integration.
• Experience with Docker, CI/CD pipelines, and modern cloud-native development practices.
• Experience working on live products with real production workloads.

AI & Modern Engineering Expectations

• Strong hands-on experience using AI-powered development tools such as Claude Code or similar as part of the day-to-day engineering workflow.
• Up-to-date understanding of modern AI capabilities and their practical application in software development.
• Ability to use AI tools to accelerate development, improve code quality, support architectural decisions, and increase engineering productivity.
• Experience with Spec-Driven Development (SDD) or similar methodologies that enable AI-native development workflows.
• Ability to identify opportunities where AI can add meaningful value to the product and its users.
• Comfortable working in an engineering environment where AI-assisted development is an integral part of the software development lifecycle.

Communication

• English level B2 or higher.
• Ability to communicate technical concepts clearly to both technical and non-technical stakeholders.
• Strong written communication and documentation skills.
• Comfortable working within distributed international teams.

Personal Qualities

• Strong ownership mentality and proactive approach.
• Ability to identify issues early and drive solutions independently.
• Open-minded and adaptable when evaluating technologies and approaches.
• Focus on code quality, maintainability, and long-term sustainability.
• Collaborative attitude and strong teamwork skills.

Join an international engineering team building a high-performance data platform used by Fortune 500 companies. As a Middle Java Engineer, you’ll work with distributed, multithreaded systems, solve real-world production challenges, and deepen your expertise with mentorship from senior engineers. Fully remote across Europe, with long-term collaboration and the opportunity to grow in the data engineering domain.

About Our Client
Our client is a leading enterprise data platform company building an open, high-performance data lakehouse for AI and analytical workloads. The platform combines an intelligent SQL query engine, an AI-ready semantic layer, and an open catalog built on Apache Iceberg — enabling Fortune 500 companies across finance, energy, manufacturing, and logistics to unify, query, and govern data at massive scale across cloud and on-premise sources.
 

About the Role
We are looking for a Middle Software Engineer (1.5–3.5 years of experience) to join the sustaining engineering team for the data catalog and enterprise data management layer of a large-scale lakehouse platform — the services that automate data ingestion and optimize Apache Iceberg tables for existing customers. The team's mandate is to keep these services running reliably for current clients: investigating and fixing customer-reported issues, resolving defects, addressing performance regressions, and keeping dependencies and security patches current. This is a maintenance and support role, not a feature-development role.
 

This is a backend Java role in a multithreaded, distributed environment where stability and availability for production customers are the baseline expectations. You will work with hands-on mentorship from senior engineers and in daily collaboration with US-based engineering leads and support teams.

Responsibilities
 

• Investigate, reproduce, and fix customer-reported issues and defects in the catalog and data-management services (Java)
• Diagnose production problems from logs, metrics, and thread or heap dumps, and work with support teams and solution architects on customer escalations
• Address performance regressions and stability issues in multithreaded, distributed services.
• Keep the services current: dependency and library upgrades, security patches, and compatibility fixes
• Write regression tests and small supportability improvements (logging, metrics, diagnostics) so issues are easier to catch and triage next time
• Take part in code reviews and follow the team's release and hotfix process
• Track and apply relevant upstream fixes from the Apache Foundation open-source projects used by the platform

• Communicate status, root causes, and blockers clearly in daily syncs with US-based engineering leads

   

Required Qualifications

• B.S. or M.S. in Computer Science or a related field 
• 1.5–3.5 years of professional software engineering experience, preferably in backend or data-intensive systems
• Strong Java programming skills: solid command of the language, the JVM ecosystem, and standard tooling (Maven or Gradle, JUnit)
• Comfortable debugging and supporting production systems — reading logs and stack traces, reproducing issues, and finding root causes
• Good grounding in data structures and algorithms
• Working knowledge of multithreaded and asynchronous programming in Java (java.util.concurrent, executors, futures) and the motivation to go deeper
• Care for engineering quality — tests, code reviews, and an understanding of why availability, resiliency, and zero-downtime upgrades matter 
• Comfort with a fast-moving environment, ownership of your work, and an eagerness to learn from and be mentored by senior teammates
• Comfortable with AI-assisted development workflows — using modern AI tools productively while critically validating their output
• English Upper-Intermediate or higher (B2+) — daily written and verbal communication with a US-based engineering team

• Availability to work EU business hours shifted 2–3 hours later for daily overlap with US West Coast mornings
   

  Desired Skills

• C++ experience — reading or writing performance-sensitive native code
• Exposure to database internals or query planning
• Familiarity with distributed systems concepts: concurrency control, data replication, storage systems 
• Middle Software Engineer – Catalog, EDM
• Apache Iceberg or other open table formats (Delta Lake, Hudi)

• Messaging systems: Kafka, NATS, or cloud pub/sub servicesи Contributions to open-source projects (Apache projects especially valued)
   

  Details

• Engagement: Long-term contract
• Location: Europe (EU / EEA / UK), remote
• Working hours: EU business hours, shifted 2–3 hours later for daily overlap with the US West Coast team

We are extending our Integrity teams and seeking for several Senior/Principal Backend Engineers for IC (Individual Contributor) and Tech Lead roles with strong expertise in Java, backend technologies and AWS serverless. This role is ideal for engineers passionate about designing and delivering intuitive, high-performing, and reliable user interfaces that support our award-winning educational platform.

This role is ideal for engineers passionate about building scalable distributed systems, data modeling, and delivering high-performing, reliable software solutions for our award-winning educational platform.

As a core contributor to our shared services team, you will play a key role in developing and enhancing the foundational systems that power both existing and new applications. This role is fully hands-on, requiring active involvement in coding, development, and implementation of technical solutions.

Responsibilities: 

• Lead and design, development, and optimization of scalable backend services using Java and serverless technologies (e.g., AWS Lambda, DynamoDB, etc).
• Architect and implement RESTful APIs and event-driven systems to support high-performance, distributed applications.
• Provide technical leadership to the team, ensuring alignment with architectural standards and best practices.
• Contribute to the development and integration of user-facing frontend components when needed.
• Analyze and optimize existing services to enhance performance, scalability, and cost-efficiency.
• Collaborate with cross-functional teams, including Architects, Product Managers, and engineering leads, to deliver innovative and impactful solutions.
• Mentor and guide junior developers, fostering a culture of continuous learning and knowledge sharing.
• Oversee the implementation and maintenance of CI/CD pipelines to ensure efficient and reliable software delivery.
• Maintain high standards of code quality through rigorous peer reviews, comprehensive testing, and adherence to industry best practices.
• Create comprehensive documentation for the developed shared components, including usage guidelines and examples.

Requirements:

• Over 10 years of experience in backend development with deep proficiency in Java and extensive hands-on experience with serverless frameworks (e.g., AWS Lambda, Google Cloud Functions).
• Solid understanding of frontend technologies, including React and Web Components, with the ability to contribute when needed.
• Expertise in designing and managing distributed systems, ensuring scalability, and advanced data modeling techniques.
• Demonstrated ability to lead and collaborate effectively with cross-functional teams and stakeholders across multiple locations, including distributed teams in Europe and the USA, to deliver impactful, high-quality solutions.
• Practical expertise in cloud technologies, specifically developing serverless applications on AWS using services such as Lambda, DynamoDB, API Gateway, SNS/SQS, and EventBridge.
• Deep understanding of software development best practices, including design patterns, test-driven development (TDD), and clean code principles.
• Experience implementing and managing CI/CD pipelines for automated build, deployment, and testing.
• Familiarity with modern DevOps practices and infrastructure-as-code (IaC).
• Proven ability to conduct comprehensive system design reviews, ensuring architectural alignment, scalability, performance, and adherence to best practices.
• Proven experience as a Tech Lead, with a strong track record of mentoring and coaching junior engineers, promoting skill development, and driving adherence to best practices to ensure team growth and technical excellence.
• Exceptional collaboration skills, working effectively across cross-functional teams, including Product Managers, Architects, and other engineering leads.
• Ability to communicate complex technical concepts clearly to both technical and non-technical stakeholders.
• Strong problem-solving skills, with a track record of troubleshooting and optimizing existing systems for performance, scalability, and cost efficiency.
• Ability to make strategic technical decisions while balancing project deadlines and business goals.

About Our Client

Our client is a leading enterprise data platform company building an open, high-performance data lakehouse for AI and analytical workloads. The platform combines an intelligent SQL query engine, an AI-ready semantic layer, and an open catalog built on Apache Iceberg — enabling Fortune 500 companies across finance, energy, manufacturing, and logistics to unify, query, and govern data at massive scale across cloud and on-premise sources.

About the Role

We are looking for a Senior Software Engineer for the team that owns the reliability and operational excellence of a large-scale data platform, delivered both as a cloud service and as self-managed software. You will work across the full platform — observability, security, control plane, and core services — diagnosing complex issues and delivering durable fixes across cloud, hybrid, and on-premises environments, in close collaboration with product engineering, SRE, support, and field teams.

This is a backend platform engineering role focused on distributed systems reliability — not application development or CRUD services.

Responsibilities

• Investigate, diagnose, and resolve complex issues across cloud and self-managed deployments — distributed systems failures, performance degradation, and reliability incidents
• Own bug fixes and targeted improvements across core services, control plane, security, and observability infrastructure
• Support automated deployment and integration frameworks that enable consistent, repeatable delivery across cloud, hybrid, and on-premises environments
• Contribute to cluster lifecycle management, observability, and operational supportability capabilities
• Partner with SRE, support, and field teams to triage and resolve escalated customer issues
• Build runbooks, root cause analyses, and internal tooling that reduce time-to-resolution over time

• Collaborate with product engineering so that fixes are integrated back into the main codebase effectively

   

Required Qualifications

• Bachelor's or Master's degree in Computer Science or a related field, or equivalent experience
• 5+ years of software engineering experience with strong hands-on Java development at production scale
• Proficiency in Python and Bash for scripting, automation, and tooling
• Solid foundation in data structures, algorithms, and multi-threaded / asynchronous programming models
• Experience designing, debugging, and operating large-scale distributed systems or microservices
• Hands-on experience with Kubernetes and Docker across cloud, hybrid, or on-premises deployments
• Cloud-native development experience on one or more of AWS, Azure, or GCP
• Strong understanding of networking fundamentals (TCP/IP, DNS, HTTP)
• Clear communicator — able to explain problems, root causes, and solutions to technical and non-technical audiences
• Comfortable with AI-assisted development workflows — using modern AI tools productively while critically validating their output
• English Upper-Intermediate or higher (B2+) — daily written and verbal communication with a US-based engineering team
• Availability to work EU business hours shifted 2–3 hours later for daily overlap with US West Coast mornings

Desired Skills

• Observability platforms: OpenTelemetry, distributed tracing, metrics, logging
• Background in data processing, data warehouse, data lake, or analytics systems
• Distributed file and object storage: S3, ADLS, or HDFS
• Infrastructure-as-code (Helm, Terraform) and CI/CD tooling (Jenkins, ArgoCD)
• Identity, authentication, and authorization systems: SSO, OAuth, SAML, RBAC
• NoSQL databases (MongoDB, RocksDB), Redis, or partner/OEM integration patterns

• Query processing, concurrency control, data replication, or storage systems

   

Details

• Engagement: Long-term contract
• Location: Europe (EU / EEA / UK), remote
• Working hours: EU business hours, shifted 2–3 hours later for daily overlap with the US West Coast team

Experience: 10+ years
Project Duration: November 2, 2026 – March 31, 2027
Location: Hybrid, Kraków, Poland

About the Project

We are looking for a Senior Java Developer to build and maintain backend services and microservices using Java and Spring Boot. The role involves working with relational databases, containerization technologies, and Azure-based solutions in a collaborative development environment.

Responsibilities

• Develop backend services using Java and Spring Boot.
• Build, maintain, and support microservices.
• Work with relational databases, including PostgreSQL, Oracle, or Sybase.
• Deploy and manage applications using Docker and Kubernetes.
• Support solutions hosted on Microsoft Azure.
• Work in Unix/Linux environments.
• Collaborate with the development team to deliver project objectives.

Requirements

• 10+ years of professional experience.
• Strong knowledge of Core Java and Spring Boot.
• Hands-on experience with microservices architecture.
• Experience working with PostgreSQL or Oracle databases.
• Experience with Docker and Kubernetes.
• Experience with Microsoft Azure.
• Good understanding of Unix/Linux environments.
• Ability to collaborate effectively with other developers.

Tech Stack

• Java / Core Java
• Spring Boot
• Microservices
• PostgreSQL
• Oracle / Sybase
• Docker
• Kubernetes
• Microsoft Azure
• Unix/Linux

Senior Java Engineer 

About the Project

We are looking for a Senior Java Engineer to join a FinTech project based in Finland, where technology is used to solve complex business challenges in the financial sector.

This role involves more than software development. It requires active participation in finding effective business solutions. We are looking for an engineer who is eager to understand client needs, work with incomplete requirements, propose practical ideas, and take ownership of the final outcome.

An important part of the role is using modern AI tools in software development, including Claude Code, while maintaining high standards of software quality and security.

Responsibilities

• Develop and maintain software solutions using Java and Spring Boot.
• Analyze client business needs and translate them into effective technical solutions.
• Work with requirements, ask clarifying questions, and improve technical specifications in collaboration with product and domain experts.
• Participate in prioritization and identify the best approaches to implementing tasks.
• Use AI tools, including Claude Code, to improve development efficiency.
• Review, refine, and deploy AI-generated code while ensuring quality, reliability, and security.
• Write unit and integration tests and maintain high code quality standards.
• Work with PostgreSQL, Vue.js, Bitbucket, and CI/CD processes.
• Follow information security and code security requirements and maintain the necessary documentation.
• Organize work independently, identify risks early, and seek help when necessary to maintain quality.
• Take ownership of the final deliverables and their business value.
•  

Requirements

• Commercial experience with Java and Spring Boot.
• Hands-on experience with PostgreSQL.
• Knowledge of unit and integration testing principles.
• Experience with CI/CD and version control systems, particularly Bitbucket.
• Practical experience using AI tools in software development and an understanding of the challenges associated with AI-generated code.
• Understanding of secure software development principles.
• Strong analytical and systematic thinking skills and the ability to solve complex problems.
• Ability to work with incomplete requirements, ask the right questions, and propose well-reasoned solutions.
• Proactive mindset, strong sense of responsibility, and ability to drive tasks to completion.
• Ability to work effectively under tight deadlines without compromising quality.
• Fluent English.
•  

Nice to Have

• Experience in FinTech or another financial domain.
• Understanding of accounting principles.
• Experience with investment fund accounting.
• Knowledge of asset management.
• Understanding of lending and private credit.
• Experience with Vue.js.
• Experience integrating AI tools into development workflows and CI/CD processes.
•  

Tech Stack

• Backend: Java, Spring Boot
• Database: PostgreSQL
• Frontend: Vue.js
• Version Control & CI/CD: Bitbucket, CI/CD
• AI-Assisted Development: Claude Code

Project Description:

Join our Development Centre in Bucharest and become a member of our open-minded, progressive and professional team. In this role you will be working on projects for one our world famous clients. You will have a chance to grow your technical and soft skills, and build a thorough expertise of the industry of our client. On top of attractive salary and benefits package, Luxoft will invest into your professional training, and allow you to grow your professional career.

As a Senior Backend Engineer you will be specifically responsible for developing backend services, supporting various applications and business requests as part of a global team.

We are seeking a skilled and collaborative Java Developer to join our engineering team. In this role, you will contribute to the design, development, and maintenance of our high-performance securitization platform. You will work within a modern microservices architecture, leveraging Spring Boot, robust messaging systems, and relational databases to deliver scalable and secure financial technology solutions
For this role, office attendance is 3 days per week.

Responsibilities:

· Feature Development: Design, build, and maintain efficient, reusable, and reliable Java code within a microservices architecture.

· Database Management: Write optimized queries and design schemas utilizing PostgreSQL.

· System Integration: Implement messaging and event-driven patterns using Pub/Sub systems.

· Code Quality: Adhere to clean code principles, conduct thorough code reviews, and write comprehensive unit/integration tests.

· Collaboration: Work closely with cross-functional team members to refine requirements, estimate tasks, and deliver features in an Agile environment.

· Develop new technology applications in partnership with Business and Operations stakeholders to transform the Issuance business

· Working in a global environment with distributed delivery teams developing micro services to meet the functionalities required by the business

· Participate in full development cycle

· Work with QAs and BAs on functional and non-functional requirements

· Collaborate with other teams to build systems and integrate them together

· Collaborate with the architects and engineering community to help define an architectural roadmap and individual solution designs that fit within that roadmap

· Support and enforce automated unit/integration testing as a standard development practice

· Ensure that the software built is reliable and easy to support in production

· Structure the delivery of program elements into epics & stories, and facilitate integration between various teams’ output for production releases, with support from BA, Architects, and Scrum Masters / Product Owners

Mandatory Skills Description:

· Java 21+: Strong proficiency in modern Java (Java 21 or higher), utilizing its latest language features and performance enhancements.
· Spring Framework: Hands-on experience with the Spring Boot ecosystem (Spring Boot 3.x, Spring MVC, Spring Data).
· Architecture: Proven experience building and deploying scalable microservices.
· Database: Solid experience with PostgreSQL (schema design, query optimization, and indexing).
· Messaging: Familiarity with event-driven architecture and Pub/Sub messaging patterns (e.g., Google Cloud Pub/Sub, Kafka, or RabbitMQ).
· Software Craftsmanship: Strong commitment to clean code, SOLID principles, and automated testing (JUnit/Mockito).
· Experienced in designing and developing Microservices systems using the following Tech Stack: Java, Spring Boot, Hibernate, Kubernetes, Helm, Maven, Git, Jenkins/TeamCity.
· Experienced in developing and deploying microservices leveraging cloud technologies. GCP knowledge.
· Strong technical vision and hands-on experience in software development and test automation, including BDD and TDD
· Experience building message-driven applications
· Prior experience working with Scrum practices and Agile software methodologies and tools (Jira, Confluence)
· Ability to develop reusable and performant clean code aligned with good architectural and design principles.

Nice-to-Have Skills Description:

· Cloud Platform: Hands-on experience with Google Cloud Platform (GCP) services (e.g., GKE, Cloud SQL, BigQuery).

Project Description:

Join our Development Center in Bucharest, and become a member of our open-minded, progressive and professional team. In this role you will be working on projects for one our world famous clients.
You will have a chance to grow your technical and soft skills, and build a thorough expertise of the industry of our client. On top of attractive salary and benefits package, Luxoft will invest into your professional training, and allow you to grow your professional career.

Responsibilities:

Implement highly scalable, secure, and resilient backend solutions using Java and Spring Boot.
Develop, test, and document software components in accordance with requirements, actively contributing to all stages of the software development lifecycle.
Maintain high standards of software quality by adhering to good practices and habits, including thorough code reviews and contributing to technical standards.
Identify and resolve complex technical issues, ensuring system stability and performance.
Leverage Google Cloud Platform (GCP) services to build, deploy, and manage robust scalable software solutions.
Collaborate with BAs, QAs, and stakeholders to jointly develop effective solutions.
Provide support to ensure high-quality releases.

Mandatory Skills Description:

Extensive Java and Spring Framework (Spring Boot, Spring Data JPA, Spring Security, and Spring Cloud) experience.
Deep JPA & Hibernate expertise with strong SQL knowledge.
Proven hands-on experience with GCP (Cloud Run, GKE, Cloud SQL, Pub/Sub, etc.).
Experience with building and consuming RESTful APIs.
Solid understanding of software design patterns and architectural principles.
Experience building containerized services (Docker, Kubernetes).
Working knowledge of Maven, Webpack, Postman, OpenAPI specifications, and testing frameworks for unit/integration testing.
Familiarity with OAuth2 flows and secure API practices.

We are a Norwegian logistics-tech company that negotiates freight agreements and manages carrier relationships for e-commerce businesses of every size, from new startups to established brands. 

Profrakt negotiates freight agreements for more than 1,500 Norwegian online stores and businesses, from new startups to established brands. It pools their combined volume to get better prices than they could get alone. Customers deal with one partner and one agreement instead of many, while still getting access to carriers such as Bring, PostNord, Helthjem, Porterbuddy, Instabox and UPS. 

The Profrakt Portal is the customer’s daily workspace. Through it, businesses can:

• Book B2C and B2B shipments, from small parcels to pallets and heavy goods
• Have the system pick the best carrier for each shipment based on price, speed and service
• Print shipping labels, including cloud printing directly to connected label printers
• Track shipments and search, filter and export their shipment history
• Create return shipments and book pickups
• Manage a customer register, their account and a customizable dashboard
• Handle invoicing, shipment inquiries and support requests

As the platform grows, the team is moving selected backend services from Python to Java/Spring Boot. You’ll take part in that migration without disrupting customers.

You’ll also turn quickly built features into reliable production services and improve the data layer behind pricing, booking, tracking and invoicing.

Main Responsibilities:

- Design, build, and maintain scalable backend services and REST APIs using Java 17+ and Spring Boot

- Rewrite selected services from Python to Java, keeping behavior consistent and making sure nothing breaks during the transition

- Review AI-generated and rapidly prototyped code for correctness, security, performance, and maintainability, and turn it into production-grade software

- Design and optimize relational database schemas and queries (PostgreSQL/MySQL), with attention to performance and data integrity

- Improve the existing codebase through refactoring and test coverage.

Requirements:
- 5+ years of experience in Java development (Java 17+)
- Strong hands-on experience with Spring Boot (Spring Web, Spring Data JPA, Spring Security)
- Deep knowledge of PostgreSQL and/or MySQL: schema design, indexing, query plans, transactions, and migrations (Liquibase)
- Knowledge of object-oriented programming (OOP), design patterns
- Git, GitHub/Gitlab proficiency
- Problem-solving and communication skills
- Frontend development with React will be a big plus
- Experience with distributed systems and message brokers (Kafka, RabbitMQ)
- Familiarity with AI coding assistants and their typical failure modes is mandatory

We offer:
— Competitive salary;
— Experience with EU markets/clients;
— Health insurance;
— Fully Remote work;
— Long-term contracts;
— Highly qualified team;
— Paid vacation (22 working days) and sick leave ( 19 days);
— Partial reimbursement of courses, training, or seminars.

🚀 AIMPROSOFT is looking for a Java Tech Lead / Solution Architect (React , Telecom) 

Aimprosoft, a fast-growing IT company, is looking for a Java Tech Lead / Solution Architect (React , Telecom) on a contract basis (≈ 4+ months) an international project in the Telecommunications / BSS-OSS domain. 

This is a senior hands-on role for an experienced Java engineer who combines solution architecture, technical leadership, and production development. You will join the project first, shape the technical foundation during discovery, and then lead a team of three Full-Stack Java Developers through the MVP delivery. 

The role is approximately 50% architecture and technical leadership / 50% hands-on production coding. 

🎯 About the project & role: 

The client is a UK wholesale internet service provider supplying broadband, Ethernet, and connectivity services to resellers and partners. 

The project is Phase 1 of a new customer and admin portal and integration platform (BSS/OSS) designed to replace manual and legacy processes and become the first production slice of the client's target platform. 

The technical environment includes: 

• Java & Spring Boot 
• React & TypeScript 
• Microservices and event-driven architecture 
• PostgreSQL 
• BPMN / workflow orchestration 
• OAuth2 / OIDC and Auth0 
• AWS 
• Docker and Kubernetes 
• CI/CD 
• TM Forum Open APIs 

🎯 Your key responsibilities will include: 

• Owning the solution architecture for the client portal and integration platform 
• Leading the initial technical discovery and helping define the MVP implementation approach 
• Designing domain models, APIs, integration flows, and event-driven components 
• Writing production Java / Spring Boot code, particularly for technically complex parts of the platform 
• Leading and mentoring a team of three Full-Stack Java Developers 
• Reviewing code and establishing engineering standards and quality gates 
• Guiding the React portal architecture and UI standards 
• Designing integrations with external and legacy systems 
• Making and documenting architecture decisions using ADRs and C4 diagrams 
• Working closely with DevOps and QA on AWS environments, CI/CD, contract testing, and integrations 
• Communicating directly with the UK client and third-party technical teams 
• Presenting technical progress through regular live demos 

🔥 What We Need From You: 

• Hands-on experience in the Telecommunications domain, ideally with ISP, BSS/OSS, broadband, order management, product catalogues, or service qualification 
• Experience with TM Forum Open APIs 
• 8+ years of commercial Java development experience 
• 2+ years as a Tech Lead, Solution Architect, or in a similar technical leadership role 
• Strong hands-on experience with Spring Boot 
• 3–4+ years of hands-on experience with React / ReactJS and TypeScript 
• English: Upper-Intermediate (B2+) / Advanced (C1) for direct communication with a UK client 
• Experience designing and delivering microservice and integration-heavy systems 
• Strong understanding of Domain-Driven Design (DDD) and event-driven architecture 
• Ability to review frontend code, guide React application architecture and contribute to frontend development when needed 
• Practical experience with reliability and integration patterns such as Transactional Outbox, idempotency, retries, and asynchronous processing 
• Experience designing REST APIs and OpenAPI-based contracts 
• Experience integrating with multiple external systems and third-party APIs 
• Practical experience with Camunda, Flowable, or a similar workflow / orchestration engine 
• Practical experience with OAuth2 / OIDC, Spring Security, and RBAC 
• Hands-on experience with AWS and containerized environments (EKS or ECS, Docker) 
• Understanding of CI/CD and modern software delivery practices 
• Experience with AI-assisted development tools such as Claude Code or Cursor 
• Experience leading developers through technical planning, code reviews, mentoring, and delivery 

📌 Nice to have: 

• Experience with PostgreSQL, Flyway, or Liquibase 
• Experience with Kafka or AWS SQS 
• Experience with Terraform or AWS CDK 
• Understanding of multi-tenant architectures 
• Experience with Auth0 
• Experience with telecom/network systems such as RADIUS, NetBox, or IPAM 
• Experience with UK broadband ecosystems such as Openreach, PXC, or CityFibre 
• Experience leading technical discovery phases or architecture spikes 

💼 What We Offer: 

• Official military deferment (reservation); 
• A competitive salary that appreciates your skills and experience; 
• Opportunity to join a strategically important pilot team with long-term project prospects 
• Work on modern cloud-native products that deliver real-world impact 
• Exposure to AI-powered development practices and enterprise-scale engineering 
• Open environment where your ideas, technical expertise are valued 

This role focuses on executing critical migration projects within the backend infrastructure. The Backend Infrastructure team is undertaking several large-scale migrations to modernize its systems, improve reliability, and reduce maintenance overhead. This TVC position will be instrumental in performing the hands-on work required for these migrations, working closely with the infrastructure team and other BackEnd teams.

Required Qualifications:

• Ability to work from our Warsaw office
• 5+ years of hands-on experience in Java programming.
• Strong communication and interpersonal skills, with the ability to collaborate effectively within a technical team environment.
• At least Upper-Intermediate level of both spoken and written English

• Bachelor’s degree in Computer Science, Software Engineering, or a related technical field, or equivalent practical experience.

   

Nice-to-Haves:

• Experience with build tools such as Gradle, Maven, or Bazel.
• Experience with building data pipelines.
• Knowledge of Google Cloud Platform (GCP) services.

Responsibilities

• Execute Migrations: Actively participate in and drive the execution of large-scale code and system migrations across various backend services. Some examples include: 
  • Importing or upgrading third-party dependencies.
  • Building projects on GoB(Gerrit-on-Borg).
  • Performing necessary code and dependency changes in backend projects
• Code Modification and Updates: Update and refactor existing codebases (primarily Java) to align with new libraries, platforms, and infrastructure.
• Testing: Work with the Infrastructure team to create a testing plan for migrations to ensure that changes do not break running services and execute the test plans.  
• Collaboration: Work closely with the  Backend Infrastructure team and other BE software engineers to understand migration requirements, plan execution strategies, and ensure smooth transitions with minimal disruption.
• Problem Solving: Investigate, debug, and resolve technical issues and complexities encountered during the migration processes.
• Documentation: Maintain clear and concise documentation for migration plans, processes, changes made, and outcomes.
• Best Practices: Adhere to software development best practices, ensuring code quality, and follow established guidelines for infrastructure changes.

We offer:

• Opportunity to work on a global product used by 100+ million users worldwide.
• Competitive compensation package, including 20 paid vacation days and paid sick leave.
• Full-time office-based work (5 days per week) in a modern, comfortable office in Warsaw.
• Flexible working hours with a healthy work-life balance.
• Private medical insurance.
• English classes with a native speaker and wellness activities, including online yoga.
• Paid tech training and other activities for professional growth;
• Modern, comfortable office and a friendly, supportive engineering culture.
   
  If your qualifications and experience match the requirements of the position, our recruitment team will reach out to you in a week maximum. Please rest assured that we carefully consider each candidate, but due to the amount of applications, the review and further processing of your candidacy may take some time.

We’re looking for a Senior Back End Engineer to join a B2B SaaS platform powering 1M+ live websites for tens of thousands of businesses worldwide.

The product combines a large-scale distributed architecture with AI-powered tools for content generation, SEO, translations, image descriptions, and automated website updates. You’ll work on core services where performance, concurrency, reliability, and scalability are critical.
 

What you’ll do:

Build and scale core backend services with Java and Spring Boot.

Design distributed microservices and high-performance APIs.

Solve complex multithreading, concurrency, and performance challenges.

Work with relational and NoSQL databases and optimize data models.

Own features end-to-end, from requirements to production.

Use AI-powered development tools to improve engineering productivity.

Influence architecture and infrastructure decisions and mentor other engineers.

What we’re looking for:

5+ years of backend development experience.

Strong Java, Spring, and Spring Boot skills.

Deep understanding of multithreading, concurrency, and performance optimization.

Experience with distributed systems, microservices, and API design.

Strong database and SQL skills.

Experience with unit and integration testing.

Ability to take ownership and work independently in a cross-functional team.

Fluent English.

Nice to have: TypeScript/React, Generative AI development tools, CI/CD, or experience in high-growth B2B SaaS.

Project description

We are building the platform, which supports various information gathering and processing across the bank. The PMC application, Price Master Central (PMC) is a global reference data management application - responsible for sourcing securities/Pricing data from market vendors and internal sources and providing it to downstream clients after applying client specific rules.

Responsibilities

Manage a team

Intensive communication with project stakeholders and other teams

Evaluate and adopt new development tools, libraries and approaches to improve delivery quality

Continuous quality improvement (code reviews, fixing Sonar issues, unit/integration/E2E test coverage)

Integrate our components with different internal and external client's systems

Configure, monitor, and troubleshoot Application servers

Monitor applications, processes, scheduled jobs, collect different types of logs and metrics

Setup and improve CI/CD

Automate routine with scripting languages

Write all types of tests: unit, integration, end-to-end

Design distributed applications

Skills

Must have

Technically strong energetic individual, who can bring innovation to the group

Team lead experience from 3 years, IT experience from 7 years

Java (Core, JDBC, MT, Collections, I/O), Spring Boot

SQL.PL-SQL on Oracle DB

Container platform based on Kubernetes

REST web services, Kafka, Redis

Unix Commands and shell scripting.

Familiarity with standard data structures and algorithms.

Experience using the following tools

JIRA, Harness/uDeploy, SonarQube, TeamCity, Artifactory, Git (GHE & Bitbucket)

Logical thinking, strong analytical and problem-solving skills; innovate and solutions oriented

Effective time management skills to manage multiple priorities with flexibility on time zones and timelines

Excellent verbal and written communication skills

Bachelor's degree in computer science or equivalent work experience

Nice to have

Master's degree in computer science or equivalent work experience

Experience working with the Scrum methodology

Experience working with a NoSQL database

Experience designing and implementing microservices

Financial services technology experience preferably in reference data

Languages

English: C1 Advanced

• Project Description:

  You will join a Regulatory Reporting Platform within a large US investment bank. The platform is responsible for collecting, processing, and transforming large volumes of data from multiple internal systems to produce regulatory reports for 240 jurisdictions worldwide. In total, the platform supports around 10,000 reports across a wide range of regulatory, compliance, financial, and risk reporting areas.
  This is a large-scale, business-critical data platform operating in a highly regulated environment, where data accuracy, quality, traceability, and timely delivery are essential. The team works on building and enhancing data pipelines, implementing reporting logic, ensuring data validation and reconciliation, and supporting the generation of complex regulatory outputs.
  The project is delivered by a global distributed team with colleagues located in Ukraine, Poland, and the US, offering close collaboration with engineers, analysts, and business stakeholders across multiple regions.

• Responsibilities:

  - Design, develop, and maintain solutions for a large-scale Regulatory Reporting Platform
  - Build and enhance data processing pipelines using Java and Apache Spark
  - Implement scalable logic for data ingestion, transformation, aggregation, and enrichment from multiple internal data sources
  - Develop and optimize batch processing jobs to support the generation of regulatory reports across multiple jurisdictions
  - Ensure high standards of data quality, validation, reconciliation, and consistency throughout the reporting lifecycle
  - Translate business and regulatory requirements into robust technical solutions
  - Collaborate with business analysts, QA engineers, and cross-functional teams to deliver reporting functionality
  - Investigate and resolve data and application issues in development, test, and production environments
  - Improve application performance, scalability, and reliability for high-volume data processing workloads
  - Contribute to the design and implementation of reusable components and engineering best practices
  - Participate in code reviews, testing, and release activities to ensure high-quality deliverables
  - Work closely with distributed teams across Ukraine, Poland, and the US in an agile delivery model
  - Support continuous improvement of the platform, including monitoring, troubleshooting, and operational stability

• Mandatory Skills Description:

  - 6+ years of commercial experience with Java
  - Experience in designing and developing scalable, high-performance backend applications
  - Good knowledge of SQL and working with large datasets from multiple data sources
  - Strong problem-solving skills and ability to work effectively in a global distributed team

• Nice-to-Have Skills Description:

  - Experience in financial services, investment banking, or regulatory reporting projects
  - Familiarity with data quality, reconciliation, and control frameworks
  - Experience working with large-scale enterprise data platforms
  - Knowledge of cloud environments and modern data platform architectures
  - Understanding of CI/CD practices and automated deployment pipelines
  - Experience working in Agile / Scrum teams within a distributed global setup

• Languages:
  • English: C1 Advanced

About Flamingo

Flamingo is revolutionizing the Managed Service Provider (MSP) industry with an AI-driven, open-source platform for IT and security. Our goal is to empower MSPs with automation, optimization, and scalability tools to enhance their operations. 

Role Overview

As a Senior Back-end Engineer (Java) at Flamingo, you will design and develop scalable, high-performance back-end services and APIs using Java and Spring Boot. You will be responsible for implementing event-driven microservices, optimizing system performance, and ensuring high availability as we scale our platform. Your expertise in processing high-volume logs and integrating multiple data sources will be critical to building a robust and efficient system.

Key Responsibilities

• Design and develop scalable backend services and APIs using Java (Spring Boot).
• Architect and implement event-driven microservices with Kafka and RabbitMQ.
• Process and analyze high-volume logs efficiently to ensure scalability and real-time insights.
• Integrate and manage multiple data sources, including SQL, NoSQL, and streaming data.
• Optimize database performance using PostgreSQL, Redis, and Elasticsearch.
• Implement authentication and authorization mechanisms with OAuth, JWT, and Keycloak.
• Collaborate with front-end and DevOps teams to build a seamless and resilient system.
• Ensure code quality through automated testing, CI/CD pipelines, and best engineering practices.

Qualifications

Must-Have:

• 5+ years of experience in backend development with Java and Spring Boot.
• Experience in microservices architecture, including event-driven systems (Kafka, RabbitMQ).
• Strong knowledge of RESTful APIs, GraphQL, and WebSockets.
• Experience processing high-volume logs and working with log management tools (ELK stack, Loki, Fluentd, OpenTelemetry).
• Experience working with multiple data sources, including relational (PostgreSQL) and non-relational (Redis, Elasticsearch) databases
• Experience with containerization (Docker, Kubernetes) and cloud platforms (AWS/GCP).
• Understanding of security best practices in backend development.

Nice-to-Have:

• Experience with functional programming in Java or Scala.
• Familiarity with distributed tracing (e.g., Jaeger, Zipkin) for microservices.
• Knowledge of cloud-native architectures and serverless frameworks.
• Exposure to message queues and event sourcing.

Why Join Flamingo?

• High-impact role: As a back-end engineer, your contributions will directly shape Flamingo’s product and technology.
• Innovative Tech Stack: Work with cutting-edge open-source technologies in AI, automation, and security.
• Remote-first Culture: Flexibility to work from anywhere while collaborating with a top-tier team.
• Mission-Driven Company: Join a team passionate about disrupting the MSP industry and making enterprise-grade security and IT automation accessible to all.