Senior Java Backend Engineer

Description

Job Summary: We are seeking a Senior Java Backend Engineer to develop innovative IT solutions in a collaborative and dynamic environment that values ideas and creativity. Key Highlights: 1. Collaborative, dynamic environment full of opportunities for personal growth 2. Values ideas, encourages creativity and individual contribution 3. Development of innovative IT solutions for global clients **Join Data Group!** At **Data Group**, we make technology simple and accessible by creating innovative IT solutions that support clients worldwide. We are expanding in Portugal and believe that growing alongside leading companies is only possible when we also grow alongside our talents. Here, people are at the heart of everything we do. We value ideas, encourage creativity, and believe every contribution makes a difference. If you seek a collaborative, dynamic environment full of opportunities to surpass yourself, your next challenge may be with us! ##### **Who Are We Looking For?** **Senior Java Backend Engineer.** **Mandatory Technical Skills and Knowledge:** * **8+ years of professional experience with Java**, including at least **3 years with Java 17 or Java 21**; * Solid knowledge of the latest Java features, notably **records, sealed types, pattern matching**, and, where applicable, **virtual threads**; * Proven, hands-on experience with **Spring / Spring Boot** in production environments; * Solid, proven experience with **reactive programming using Project Reactor or RxJava**, including Mono/Flux, backpressure, retry/backoff, and hot vs. cold publishers; alternatively, solid experience with asynchronous programming using **CompletableFuture and structured concurrency**; * Professional experience with **gRPC + Protobuf**, including streaming RPCs, deadlines, interceptors, and schema evolution; * Solid knowledge of **concurrency**, including thread-safety, executor sizing, lock-free patterns, and thread lifecycle management; * Solid experience with testing using **JUnit 5, Mockito and AssertJ**, including integration tests with real dependencies and contract/parity testing; * Experience with **Kafka**, including consumer/producer semantics; * Production experience with at least one of the following technologies: **Redis, PostgreSQL or MongoDB**; * Experience with **Cloud/AWS** or equivalent, notably **S3, IAM, managed Kafka and container runtimes**; * Excellent **written communication and technical documentation skills**, including design documents, postmortems and pull request documentation; * **Minimum English level C1 – mandatory and disqualifying requirement**; * **Fluent Spanish – mandatory and disqualifying requirement**. ##### **Desirable Technical Skills and Knowledge:** * Experience leading **complex migrations or refactorings** in multi-module codebases; * Experience with **container packaging and multi-arch builds**, specifically Linux/AMD64 and Linux/ARM64; * Knowledge of **Python**, with ability to understand and debug code; * Experience with **Apache Arrow** or other columnar data formats; * Experience with **TeamCity, GitHub Actions** or equivalent tools, including CI/CD pipeline management and evolution. **Work Mode:** 100% Remote. ##### **Submit your application and join us in simplifying the future!**