Senior Java Developer IoT

O projekcie: Our goal is to develop a product that integrates with the ecosystem of various eSIM services. We provide an "entry point" that is a consistent and comprehensive set of services that enable the customer easily and transparently manage his eSIM devices. Our clients include mobile network operators, car manufacturers, payment terminal providers and many others. From a technical point of view, we put a lot of effort into 3 elements: - code quality - code review culture, static code analysis, various types of tests,- automation - CI with code scans and automatic tests,- everything as code - infrastructure as code, tests as code, and even code as code. As a team, we place great emphasis on sharing knowledge. We try to be as multifunctional as possible. In addition to your standard duties, you will take part in the requirements technical analysis, support QA team in their activities and many more. You will be working on a real IoT platform, where backend services communicate with devices and cloud components. The system processes asynchronous, event-driven data flows, handles unstable connectivity, and runs in a cloud-native, containerized environment. The project includes: - device ↔ backend ↔ cloud communication,- event-driven and asynchronous processing,- cloud-native deployment,- scalability, reliability and observability,- security mechanisms based on encryption, certificates and credentials,- containerized environments. Wymagania: Necessary Skills: - strong, hands-on experience with Java 17 / Java 21,- commercial experience with Kotlin- proven experience in designing and developing backend systems for distributed environments,- deep understanding of asynchronous and event-driven architectures,- ability to design clean, maintainable and testable codebases,- experience working with code reviews, technical leadership and mentoring,- strong understanding of system reliability, scalability and fault tolerance. Required Experience (Hands-on): You are expected to work independently and lead by example in: - Spring ecosystem (Spring Boot, WebFlux),- Docker and containerized applications,- Kubernetes (designing and operating services in k8s),- Git / Bitbucket workflows,- CI/CD pipelines (Jenkins),- Azure cloud environment,- cloud-native application design principles (12-factor app),- relational databases (MySQL, MariaDB),- security fundamentals (TLS, symmetric / asymmetric cryptography, secrets management). Nice to Have: - experience with IoT platforms or large-scale distributed systems,- experience with messaging systems (Kafka, RabbitMQ, MQTT),- experience designing event-driven and eventually consistent systems,- knowledge of cloud architecture patterns,- experience with Camunda or other BPMN / workflow engines,- experience collaborating closely with QA and DevOps on quality and automation. Codzienne zadania: - design and evolve backend architecture for IoT systems, - implement complex, business-critical backend components, - make architectural and technical decisions within the team, - ensure system scalability, reliability and security, - review code and mentor Regular and Junior developers, - collaborate closely with QA engineers on test strategies and E2E scenarios, - actively contribute to CI/CD and deployment strategies, - support troubleshooting of production issues and root-cause analysis, - work closely with architects, product owners and team leader