Senior Backend Engineer - Java Payments

Job description: Why We're Hiring Now We're a game development studio launching our own gaming platform, and the platform team is building against a live launch date. The wallet/ledger system and the partner-facing APIs need to be production-ready before our first third-party integrations go live. We're adding engineers to that team now — not next quarter. If you're the kind of engineer who sweats the details — the race condition nobody else noticed, the retry that could double-charge a user, the edge case hiding in a timeout — we'd like to talk this week. About the Role This is a greenfield build. There's no legacy system to babysit, but there is a deadline and real money moving through the code. You'll own a core piece of the platform end to end — most likely the wallet/ledger or the real-time transaction path — working directly with the senior engineers shaping the rest of it. The APIs you design become long-term contracts for third-party integrators. The accounting code you write has to balance. What You'll Do Build and own core components of the wallet/ledger system — transactional correctness, idempotency, and reconciliation across the full transaction lifecycleImplement partner-facing APIs — authentication and request signing, error code conventions, versioning, callback and retry semanticsBuild high-concurrency real-time services — persistent connection management, low-latency transaction pipelines, load testing and capacity planningOwn observability for what you ship — metrics, alerting, distributed tracing, plus a share of on-call and incident postmortemsWeigh in on architecture — we expect you to challenge designs you disagree with, and to argue from reasoning rather than rankWhat We're Looking For 4+ years building and operating backend services in production, ideally distributed or real-timeStrong relational database fundamentals: transactions, isolation levels, locking, and indexing under concurrent loadSolid grasp of multi-threaded and asynchronous processing — you know where the races hideShipped or operated at least one transactional system: payments, wallets, ledgers, or in-game economiesStrong Java (we use Java 17 / Spring Boot 3.4), or strong fundamentals in a comparable language and ready to switchWorks well in a small, opinionated, collaborative teamChinese mandarin fluentNice to Have Prior experience with game servers, in-game economies, or live opsComfortable with on-call rotations and owning incidents end to endAble to assess what a system or codebase needs and make the case to prioritize itSelf-directed; willing to pitch in beyond your direct scopeBenefits 401(k) plan eligibilityMedical, dental, and vision coverageLife insurance13 paid holidays per calendar yearPaid vacation: 10–20 days per calendar yearUp to 5 paid sick days per calendar yearJob Type: Full-time Benefits: 401(k)401(k) matchingDental insuranceFlexible scheduleHealth insurancePaid sick timePaid time offVision insurance