Senior Backend Developer (Java) - Mobile Game Platform

We are hiring a Senior Backend Developer to maintain and extend the backend for a live mobile game (Cocos C++ client + Java services). You will work on gameplay APIs, player data integrity, ranking systems, payments, and platform services in a high-traffic production environment.

Build and maintain Java backend services that power core gameplay and account flows.

Implement and evolve request handlers behind the game protocol endpoint (`/bnb/operation`) using `requestKey` dispatching.

Own data consistency across MySQL + Redis, including transactional and partial-failure edge cases.

Extend ranking, activity, and account transfer systems used by live players.

Integrate and support payment verification flows (Google Play / iOS / PayPal).

Collaborate with client engineers by tracing C++ network behavior and shared JSON contracts.

Strong Java 11 experience in production systems.

Spring MVC (XML-based configuration), Spring Security, Spring JDBC/Tx.

MyBatis (annotation-driven DAO patterns), not JPA/Hibernate.

Maven multi-module project experience.

Deep understanding of HTTP/HTTPS API design and production debugging.

Experience with JSON-based messaging (Fastjson/Jackson/Gson interoperability).

Ability to work with command-style API routing (single endpoint + operation key) rather than conventional REST resource routing.

Familiarity with gzip-compressed request/response handling.

MySQL schema design and performance tuning.

Redis (Jedis), including sorted sets, TTL patterns, and cache invalidation.

Confidence handling consistency between relational DB writes and Redis updates.

Leaderboards, player progression data, event systems, and anti-cheat validation logic.

Handling high-frequency state updates and large player-state payloads safely.

Idempotency, concurrency control, and rollback strategy for critical flows.

Ability to read C++ code to understand client request construction and field contracts.

Comfortable debugging cross-language issues between Cocos C++ client and Java backend.

Experience with legacy Spring MVC modernization.

Prior migration of old connection pools (e.g., BoneCP) to HikariCP.

Experience with Google App Engine or similar cloud runtimes.

Experience with distributed locking (Redis / ZooKeeper/Curator).