Jobs Java

Level: Senior Engagement: Long-term contract Location: Europe (EU / EEA / UK), remote Working hours: EU business hours, shifted 2–3 hours later to ensure daily overlap with US West Coast (PST/PDT) mornings

About the 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 to design, build, and own significant components of the core query engine of a large-scale distributed data platform. You will lead work across query planning, optimization, and execution — driving architectural decisions, mentoring middle engineers, and pushing the platform's performance and scalability boundaries across all major clouds.

This is a systems-level, backend engineering role focused on distributed data processing internals — not application development or CRUD services.

Responsibilities

• Architect, design, and implement significant components of the query engine — planner, optimizer, execution operators, memory management, and data access layers.
• Write and review high-quality, performance-critical code in Java and/or C++.
• Own end-to-end delivery of features from technical design through production rollout.
• Drive performance optimization work — profiling, benchmarking, and eliminating bottlenecks in latency- and throughput-sensitive paths.
• Integrate deeply with columnar formats, open table formats, and connectivity drivers.
• Mentor middle engineers, lead code reviews, and set technical standards for the team.
• Contribute to CI/CD architecture and quality processes across Jenkins, containerization, and multi-cloud deployment (GCP, AWS, Azure via Kubernetes / Docker).
• Debug complex, cross-layer issues spanning query planning, distributed execution, memory management, and I/O.
• Partner with US-based engineering leads on design reviews, architectural decisions, and roadmap execution.

Required Qualifications

• Education: B.S. or M.S. in Computer Science, Computer Engineering, or a related technical field.
• Programming: Strong proficiency in Java or C++, with deep understanding of OOP, systems design, memory management, and concurrency. Candidates strong in both are especially valued.
• SQL & Data: Advanced SQL skills and strong understanding of query execution internals — planning, optimization, and operator implementation.
• Data processing systems experience: Demonstrated experience building or extending data processing systems — query engines, distributed databases, ETL/ELT frameworks, or analytical platforms.
• Engineering experience: 5+ years in backend/systems software engineering, with a track record of owning significant components.
• CI/CD & DevOps: Solid experience with Jenkins and modern engineering workflows.
• Containers & Orchestration: Strong working knowledge of Docker and Kubernetes.
• Cloud: Hands-on experience with at least one major cloud (GCP, AWS, or Azure); exposure to more than one is a strong plus.
• Version Control: Confident with Git / GitHub workflows and rigorous code review practices.
• English: Upper-Intermediate or higher (B2+) — daily written and verbal communication with a US-based engineering team.
• Availability: Able to work EU hours with a 2–3 hour shift toward US West Coast time to ensure daily overlap with the client team.
• Leadership: Prior experience mentoring engineers, leading technical designs, or owning components end-to-end.

Desired Skills

• Deep experience with Apache Arrow (columnar in-memory format).
• Hands-on experience with Apache Calcite (SQL parsing, planning, optimization framework).
• Experience with Gandiva or LLVM-based expression compilation and code generation.
• Experience with open table formats — Apache Iceberg, Delta Lake, or Hudi.
• Deep familiarity with distributed computing frameworks (e.g., Apache Spark, Kafka) and MPP SQL query engines (e.g., Presto, Trino, or similar).
• Deep understanding of query planning, optimization (cost-based, rule-based), and execution internals.
• Experience with data connectivity drivers: JDBC, ODBC, Arrow Flight.
• Kubernetes on managed services (GKE / EKS / AKS) and multi-cloud exposure.
• IaC tools such as Terraform.
• Track record of performance optimization at the systems level — profiling, vectorization, cache/memory-conscious design.
• Prior experience contributing to open-source data infrastructure projects.

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.

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.

YASNO – бренд енергопостачальних компаній України, що забезпечують електроенергією, газом та енергоефективними рішеннями 2,5 млн сімей і понад 64 тис бізнесів.
Ми бачимо український енергоринок як активного учасника, що може створювати цінність, тому формуємо екосистему продуктів для енергонезалежності, ефективності та стійкості бізнесу.
Наша мета – розвивати рішення, які підтримують економіку та наближають країну до енергетичної незалежності, забезпечуючи українцям світло сьогодні й можливості для розвитку завтра.

Java Developer

Ключові навички:

• Досвід роботи від 5-х років на аналогічній посаді;
• Досвід роботи з Java Core, Java EE та/або Spring Framework;
• Відмінні знання сервісної, multy-tier та client-server архитектур;
• Досвід в роботі з великими JSON та XML файлами;
• Знання реляційних БД (Oracle/Azure SQL/PostgreSQL або інщі), навички написання складних SQL запитів;
• Практичний досвід роботи з async programming;
• Досвід роботи з ELK або Grafana та навички troubleshooting;
• Досвід написання Unit- та Functional-тестів;
• Досвід роботи з Jira, Confluence, Azure DevOps або подібними інструментами;
• Знання JavaScript буде плюсом.

Твоїми задачами будуть:

• Реалізація беклогу з розробки білінгової системи та її надбудов;
• Розробка інтеграцій з існуючими системами компанії;
• Проектування та реалізація архітектури;
• Забезпечення безпеки додатків використовуючи автуальні техніки, технології та методології написання коду;
• Автоматизація процесів;
• Написання та актуалізація Unit- та Functional-тестів;
• Аналіз проектної документації для повного розуміння вимог бізнесу та технічних вимог;
• Ведення документації про продукт;
• Пошук проблем за допомогою аналізу логів ті інших доступних методів.

Ми цінуємо в кандидатах:

• Відмінні навички вирішення проблем;
• Добре розвинені аналітичні здібності;
• Відповідальність;
• Вміння працювати в команді на спільний результат.

На тебе чекає:

• Команда професіоналів;
• Цікаві проєкти;
• Професійний розвиток та можливість кар’єрного зростання;
• Навчання та командоутворюючі заходи; 
• Психологічна та юридична підтримка;
• Подарунки на знакові та важливі події; 
• Сучасний офіс в UNIT.City, безкоштовний паркінг та шатл від найближчих станцій метро; 
• І звісно: офіційне працевлаштування, конкурентний рівень оплати (завжди вчасна та прозора винагорода), медичне страхування.

Якщо твій досвід є релевантним, ми з тобою зв’яжемось.