Staff/Senior Java Engineer (Web3 Wallet)

Location: Hong Kong, Hong Kong SAR, or Singapore

Company

OKX provides a self-custody Web3 wallet for securely storing, managing, and using on-chain assets across multiple chains and asset types.

What you will do

• Own and improve core wallet backend modules, including address management, asset synchronization, transaction construction, broadcasting, confirmation, gas estimation, nonce management, and transaction-state tracking.
• Build transaction scenarios covering transfers, token approvals, contract interactions, cross-chain operations, swaps, DApp connections, and signature requests.
• Integrate EVM, Tron, Solana, Layer 2 networks, new public chains, and additional asset standards.
• Improve operational stability through monitoring, alerting, rate limiting, retries, graceful degradation, compensation, reconciliation, and incident response.
• Drive backend projects from design through launch while coordinating with product, QA, frontend, infrastructure, and other backend teams.
• Use AI coding tools for development, testing, review, troubleshooting, refactoring, and documentation, validating output for correctness, performance, and security.

Requirements

• Approximately 5–10 years of Java backend development experience.
• Strong knowledge of Java collections, concurrency, thread pools, JVM behavior, network communication, performance optimization, and Spring Boot, Spring Cloud, MyBatis, or comparable technologies.
• Experience designing complex or high-concurrency systems using idempotency, retries, compensation, caching, message queues, distributed locks, consistency controls, rate limiting, and service degradation.
• Experience with wallets, blockchain, trading platforms, on-chain data services, or related systems; knowledge of addresses, keys, mnemonics, signing, broadcasting, confirmation, gas, nonce, and at least one of EVM, Tron, or Solana.
• Strong security awareness covering private keys, signing, authentication, tamper resistance, sensitive-data protection, least privilege, replay protection, duplicate requests, and data-leak risks.
• Ability to troubleshoot production issues using logs, metrics, distributed tracing, and thread or memory analysis; willingness to work with AI coding tools and concepts such as prompts, RAG, AI agents, and MCP.

Nice to have

• Experience integrating public chains, asset standards, cross-chain protocols, WalletConnect, DApp browsers, or signature-request systems.
• Knowledge of MPC, multisig, hardware wallets, TEE-based key security, DeFi, swaps, staking, bridges, or risk-control systems.
• Experience with RPC calls, block scanning, chain reorganizations, transaction compensation, reconciliation, JVM tuning, and complex production incidents.
• Practical AI projects such as AI code review, development agents, MCP servers, intelligent troubleshooting, or knowledge bases.

Culture & Benefits

• Competitive total compensation.
• Comprehensive insurance coverage for employees and dependents.
• Additional benefits discussed after joining.