4Bell Technology

Job Description

Key Responsibilities

•     Design and implement net-new Spring Boot microservices per approved OpenAPI 3.1 specifications — each service independently deployable, fully tested, and integration-ready

•     Enhance and upgrade existing legacy Java services to Spring Boot 3.x / Spring Framework 6.1 baseline, including javax.* → jakarta.* namespace migration

•     Write comprehensive unit and integration tests targeting ≥80% code coverage using JUnit 5 and Mockito

•     Participate actively in code reviews — both receiving and providing feedback to peers to maintain team-wide quality standards

•     Confirm implementations align to OpenAPI 3.1 contract specifications before SIT handoff

•     Document non-standard patterns or legacy findings encountered during development and escalate to the Tech Lead

•     Contribute to service retirement analysis when assigned — impact assessment, dependency mapping, and decommission documentation

•     Deliver consistently to wave-level schedules, maintaining SIT-readiness at dev close for each delivery cycle

•     5+ years of professional Java development with hands-on Spring Boot microservices experience in production environments

•     Strong working knowledge of Spring Boot 3.x, Spring Framework 6.1, and Java 17

•     Solid understanding of the jakarta.* namespace migration and Spring Boot 3.x upgrade patterns

•     Experience implementing REST APIs from OpenAPI / Swagger specifications in a contract-first workflow

•     Working experience with Apache Kafka and RabbitMQ — producing and consuming messages, configuring topics/queues, and implementing event-driven patterns in Spring Boot applications

•     Solid SQL skills and hands-on experience with Oracle and PostgreSQL in a Spring Data / JPA context — writing queries, mapping entities, and optimizing data access patterns

•     Practical knowledge of enterprise caching — Redis (cache-aside patterns, TTL management, distributed invalidation) and Spring Cache abstraction (@Cacheable, @CacheEvict, @CachePut); understands when to cache, what to evict, and how to avoid stale data issues

•     Strong understanding of Java multithreading and concurrent programming — comfortable using ExecutorService, CompletableFuture, and synchronized constructs; able to write thread-safe code and recognize common concurrency pitfalls

•     Proficient with JUnit 5, Mockito, and integration testing patterns for Spring Boot applications

•     Comfortable working in a structured offshore delivery model with code-review gates and defined acceptance criteria