Senior Software Development Engineer (Java + React)
First seen by Alion on Nov 13, 2026.
Company: Lightning Staff
Location: Remote
Employment: Full-time, B2B
About the Role
Lightning Staff is looking for an experienced Senior Java Developer for potential collaboration on international enterprise projects.
We are interested in engineers who can take ownership of backend development, work with complex integrations, optimize application performance, and contribute to frontend development when needed.
Requirements
5+ years of commercial experience with Java
Strong knowledge of Java 11/17, Spring Framework and Spring Boot
Experience with microservices architecture and REST APIs
Hands-on experience with Oracle Database and SQL
Good understanding of JVM internals, garbage collection and memory management
Experience with performance profiling, heap dumps and application optimization
Practical experience with React
Strong unit testing skills (JUnit, Mockito)
Experience with Git, Docker and CI/CD
English: Upper-Intermediate (B2) or higher
Ability to work independently and take ownership of technical tasks
Nice to Have
Experience with high-load enterprise applications
Kafka or RabbitMQ
Kubernetes
Monitoring tools (Prometheus, Grafana)
Java Flight Recorder (JFR)
Responsibilities
Develop and maintain Java/Spring Boot applications
Design and implement REST APIs and integrations
Investigate performance bottlenecks and optimize JVM applications
Write unit tests and maintain code quality
Contribute to React-based UI components when required
Participate in architecture discussions and code reviews
Collaborate with international engineering teams
What We Offer
Remote collaboration
B2B contract
Opportunities to work on international projects
Flexible working arrangements depending on the project
Technical challenges and professional growth