Senior Software Engineer (Java) - Optimizer Hub

Azul == Java. As the only company focused 100% on Java, Azul is building the Java platform for the modern cloud enterprise. We are reimagining how customers use Java, bringing them the tools and insight they need to deliver faster, more performant, more dependable, and less expensive Java services. It requires experts in many areas — hardcore experts in Java VM internals, application developers with deep knowledge of Java, backend and frontend developers, performance engineers, etc. Come join one of the most influential members of the Java and OpenJDK community and help influence the future of Java.

About the Product

Azul Optimizer Hub (OptHub) is a set of services external to the JVM within Azul Platform Prime that run in your cloud or on-premises environment. It consists of two major functions:

• Cloud Native Compiler separates the heavy lifting of compiling bytecode to optimized machine code from the actual running of Java applications.

• ReadyNow Orchestrator ensures consistent responsiveness and performance even as instances are brought up and down, and during critical times like a retail rush, start of the gaming day, or market open.

As a Senior Software Engineer on the Optimizer Hub team, you will design and build the server-side services that sit at the heart of our JVM performance platform. You will work closely with product managers, performance engineers, and JVM experts to deliver high-quality, scalable backend components.

• Design, develop, and maintain high-performance Java services including protocols, APIs, data storage, and real-time optimization engines.

• Build and evolve server-side OptHub components that communicate with the JVM at scale across cloud and on-premises environments.

• Debug complex distributed systems issues with limited diagnostic data and under performance constraints.

• Design and implement observability, profiling, and diagnostic tooling to support both internal development and customer-facing deployments.

• Drive performance analysis and improvement: create benchmarks, interpret profiler output, and act on findings.

• Participate in design discussions and code reviews, raising the bar for the whole team.

• 5+ years of strong professional Java development experience, with a focus on backend and server-side systems.

• Deep understanding of JVM internals: memory management, garbage collection, JIT compilation, and threading.

• Experience building and operating distributed systems and microservices in production.

• Proficiency with concurrency, low-latency design, and performance optimization techniques in Java.

• Experience with cloud platforms (AWS, Azure, or GCP) and container orchestration (Kubernetes).

• Ability to design clean APIs and protocols; comfort working close to the metal when needed.

• Strong debugging skills — you can track down hard-to-reproduce production issues with limited data.

• Familiarity with JVM-adjacent technologies: JVM agents, JVMTI, bytecode manipulation (ASM, Javassist), or OpenJDK internals.

• Experience with C/C++ or other low-level languages — helpful when reading JVM source or performance-critical native code.

• Background in performance engineering, profilers (async-profiler, JFR, YourKit), or runtime observability.

• Experience with gRPC, Protocol Buffers, or high-throughput messaging systems.

• Prior work in a Java platform, middleware, or infrastructure product company.

• Referral Program — help us grow with great people.

• Premium IT equipment — MacBook Pro or hardware of your choice.

• 5 weeks of holidays + 5 sick days.

• Flexible working hours; full remote possible.

• Prague city center offices.

• Work alongside top experts worldwide contributing to the Java ecosystem.