Backend Software Engineer – EV Charging Systems

About the Role

Dropcases Limited is developing technology solutions for the electric vehicle charging ecosystem, covering EV charging hardware, connected charging platforms, mobile applications and cloud-based services.

We are seeking a Backend Software Engineer – EV Charging Systems to conduct research and experimental development on server-side systems supporting EV charger communication and charging-session processing.

The role will focus on investigating and validating reliable backend mechanisms for handling concurrent charging sessions, asynchronous charger events, data consistency, system performance and recovery from partial network or service failures. The position is focused on backend R&D rather than routine software maintenance or mobile application development.

Key Responsibilities

●      Review backend transaction flows and identify technical issues involving charger-event processing, concurrent requests, data consistency and service recovery.

●      Research, develop and test Java-based backend prototypes for charger-event ingestion and charging-session state management.

●      Investigate and compare approaches for event ordering, idempotency, deduplication, retries and transaction reconciliation.

●      Conduct controlled load, concurrency and fault-recovery testing to assess response time, throughput, processing stability and transaction integrity.

●      Investigate performance bottlenecks involving JVM processes, databases, caches, message queues and service-to-service communication.

●      Develop and validate server-side recovery mechanisms for temporary network, service, database, cache or message-queue interruptions.

●      Refine backend mechanisms based on test evidence and validate server-side API behaviour against defined system and interface requirements.

●      Prepare prototype specifications, test records, benchmark results, technical findings and backend reliability recommendations.

●      Participate in regular technical reviews and R&D milestone assessments.

●      Collaborate with system architecture, mobile application, hardware and product teams on interface and integration requirements while maintaining responsibility for backend R&D deliverables.

Required Qualifications

●      Bachelor’s degree or above in Computer Science, Software Engineering or a related discipline.

●      At least five years of professional experience in Java backend or distributed-system development.

●      Strong knowledge of Java, including concurrency, multithreading, input/output processing and JVM behaviour.

●      Practical experience with Spring Boot, Spring Cloud or similar Java-based microservice frameworks.

●      Experience with distributed systems, microservices and high-availability backend services.

●      Experience with relational or distributed databases, caching systems and message queues.

●      Familiarity with technologies such as MySQL, Redis, RabbitMQ or Kafka.

●      Experience designing or testing APIs and service-to-service communication.

●      Ability to investigate backend performance and reliability issues through structured testing and technical analysis.

●      Strong problem-solving, documentation and cross-functional communication skills.

Preferred Qualifications

●      Experience with EV charging, IoT, connected devices or device-to-cloud platforms.

●      Familiarity with EV charging communication protocols such as OCPP.

●      Experience with Kubernetes, Docker or cloud-native deployment environments.

●      Experience conducting load testing, performance benchmarking or fault-injection testing.

●      Experience developing high-concurrency or fault-tolerant backend platforms.

●      Experience participating in projects developed from initial concept or prototype stage.

Expected R&D Outputs

The successful candidate will contribute to the preparation of:

●      Backend prototype modules;

●      Charging-session processing and recovery mechanisms;

●      Load, concurrency and fault-recovery test reports;

●      Backend performance and reliability findings;

●      Backend mechanism and reliability specifications;

●      Technical documentation and internal knowledge-transfer materials.

Work Arrangement

The position will be based at Dropcases Limited’s Hong Kong office. The successful candidate will be provided with a dedicated workstation and access to the required backend development, cloud-computing, testing, source-control and performance-analysis environments.