Staff/Senior Java Engineer, OKX Web3 Wallet

As a Staff or Senior Java Engineer at OKX, you own core modules of OKX Wallet, a self-custody wallet operating in a multi-chain, multi-asset, high-concurrency environment. You'll work on address management, asset synchronization, transaction construction and broadcasting, on-chain confirmation, and transaction-state tracking, combining the complex-systems challenges of traditional internet backends with the unique demands of blockchain transactions and signing.

What you'll do

• Own core wallet backend modules, building and continuously improving address management, asset synchronization, transaction construction, broadcasting, on-chain confirmation, gas estimation, nonce management, and transaction-state tracking, keeping stability, performance, and maintainability front of mind.
• Build transaction and on-chain interaction scenarios including transfers, token approvals, contract interactions, cross-chain swaps, DApp connections, and signature-request handling, understanding the full transaction lifecycle from initiation through construction, signing, broadcasting, on-chain confirmation, and final state update.
• Support multi-chain and new-chain integration across EVM, Tron, Solana, and continuously onboarded public chains and Layer 2 networks, contributing to technical research, integration design, and feature development while accounting for differences in address models, account systems, transaction structures, signing methods, fees, and confirmation mechanisms.
• Ensure stable operation by contributing to monitoring, alerting, rate limiting, graceful degradation, retries, compensation, data reconciliation, and troubleshooting, and driving systemic fixes for recurring issues such as added monitoring, stronger fallbacks, or design improvements.
• Own your projects end to end from design through development, testing, and launch, proactively syncing information across product, QA, frontend, infrastructure, and backend teams to surface dependencies, risks, and drive issues to resolution.
• Continuously raise engineering quality by participating in design discussions, code reviews, and system optimization, spotting unreasonable designs and latent risks, documenting technical decisions and post-incident learnings, and helping less-experienced teammates.
• Use AI coding tools such as Claude Code, Cursor, and Codex to assist with code comprehension, scaffolding, unit tests, code review, troubleshooting, refactoring, and documentation, validating AI output for correctness, project conventions, performance, and security.

What you bring

• Approximately 5-10 years of Java backend experience with a strong grasp of collections, concurrency, thread pools, the JVM, network communication, and common performance issues.
• Proficiency with Spring Boot, Spring Cloud, MyBatis, or comparable frameworks, able to independently design and build medium-to-large backend modules.
• Strong system design ability with experience in complex or high-concurrency systems, comfortable with idempotency, retries, compensation, caching, message queues, distributed locks, data consistency, rate limiting, and service degradation.
• Ability to understand context and goals on ambiguous problems, separate symptom from root cause, and choose solutions based on business value, user experience, stability, cost, and security.
• Independent ownership of modules and projects end to end, proactively communicating and resolving dependencies, risks, and blockers through to launch outcomes.
• Experience with wallets, blockchain, trading platforms, on-chain data services, or related systems, understanding addresses, public/private keys, mnemonics, transaction signing, broadcasting, on-chain confirmation, gas, and nonce mechanics of at least one of EVM, Tron, or Solana, and token standards such as ERC-20 and TRC-20.
• High security awareness regarding private-key, signing, permission, and user-asset security, familiar with replay protection, API authentication, tamper resistance, sensitive-data protection, and least-privilege principles.
• Ability to diagnose live issues via log analysis, metrics monitoring, distributed tracing, and thread/memory analysis with hands-on experience in performance degradation, timeouts, message backlogs, data inconsistencies, or unstable third-party services.
• Willingness to use AI coding tools to improve daily efficiency and ability to judge whether AI output meets real business requirements before shipping it.

Nice to have

• Integration work on new public chains, new asset standards, or cross-chain protocols
• Familiarity with WalletConnect, DApp Browser, or signature-request handling
• Knowledge of MPC, multisig, hardware wallets, or TEE-based key-security schemes
• Experience with Swap, staking, cross-chain bridges, or DeFi aggregation
• Address risk detection, allow/deny lists, anti-fraud, or wallet risk-control experience
• High-concurrency transaction systems, blockchain node services, on-chain data indexing, or transaction-state-tracking systems
• Familiarity with RPC calls, block scanning, chain reorgs, transaction compensation, and reconciliation mechanisms
• JVM performance tuning, stability governance, or complex production-incident experience
• Track record of cross-team collaboration and driving projects to delivery
• Real projects built with AI such as AI code review, development agents, MCP servers, intelligent troubleshooting, or knowledge bases
• Active engagement with developments in AI coding assistants and LLM applications, sharing practical takeaways with the team

What we offer

• Competitive total compensation
• Comprehensive insurance coverage for you and your dependents

About OKX

OKX Wallet is OKX's self-custody wallet, built for users worldwide to securely and conveniently store, manage, and use their on-chain assets across multiple blockchains and asset types.