Job Description

OneAPPS GmbH is a Technology consulting firm based out of Germany and offices across Europe. We are working on various projects involving diverse, multicultural teams with clients across the Germany & Europe. We are an invaluable partner and our teams have collaborated to support the growth of our clients. With more than 7 locations worldwide we help our clients to deliver their projects smoothly. We look forward to getting to know you and working with you.

Java Developer

Location: Germany

Key Responsibilities:

Design, develop, and maintain scalable Java applications for energy trading solutions. Work primarily with Spring Boot, Project Reactor, and Apache Kafka to build robust, event-driven systems. Collaborate closely with cross-functional teams to define, design, and ship new features. Write clean, efficient, and testable code, following industry best practices. Participate in code reviews and contribute to continuous improvement of our development processes. Stay up to date with emerging trends and technologies, share knowledge within the team
Requirements:

Proven experience as a Java developer in a professional environment. Strong expertise in Spring Boot and knowledge of developing RESTful APIs. Experience with Time Series data, especially with time zone handling and DST. Hands-on experience with messaging systems, especially Apache Kafka. Familiarity with reactive programming (ideally with Project Reactor). Experience in building and maintaining production-grade, distributed systems. Excellent problem-solving skills, with a proactive and self-driven approach. Effective communicator in English; German is a plus. Willingness and ability to join onsite meetings in Essen, Germany 1/2 days per month.
Job Types: Full-time, Temporary, Contract

Application Question(s):

How many years of experience do you have as Java Developer? How many years of experience do you have in Project Reactor? How many years of experience do you have in Apache Kafka? How many years of experience do you have in RESTful APIs? How many years of experience do you have in Time Series data, especially with time zone handling and DST?
Language:

* German (Required)