Resident Engineer jobs in United States

Founded in 2017, OKX is one of the world’s leading cryptocurrency spot and derivatives exchanges. OKX has adopted innovative blockchain technology to reshape the financial ecosystem by offering some of the most diverse and sophisticated products, solutions, and trading tools on the market. Trusted by more than 20 million users in over 180 regions globally, OKX strives to provide an engaging platform that empowers every individual to explore the world of crypto. In addition to its world-class DeFi exchange, OKX serves its users with OKX Insights, a research arm that is at the cutting edge of the latest trends in the cryptocurrency industry. With its extensive range of crypto products and services, and unwavering commitment to innovation, OKX’s vision is a world of financial access backed by blockchain and the power of decentralized finance.

We are seeking a talented and experienced Blockchain Developer to join X1 (zk layer2 based on Polygon CDK) or ZK-Dex (based on zkwasm) development team. As a Blockchain Developer, you will be responsible for designing, implementing, and maintaining blockchain-based solutions. Additionally, you will provide support for hackathons to encourage innovation and collaboration within the X1 community and contribute to the Polygon CDK, or participate in the design and development of ZK spot/perpetual/united account dex.

1. Blockchain Development: Design, develop, and deploy blockchain solutions, including smart contracts and decentralized applications.
2. Programming: Write clean, efficient, and maintainable code in languages such as Solidity, Go, or Rust, C++ depending on the blockchain platform being used.
3. Smart Contract Development: Create, test, and deploy smart contracts on various blockchain platforms, ensuring security and efficiency.
4. Architecture Design: Collaborate with architects and software engineers to design scalable and secure blockchain architectures that meet business and technical requirements.
5. Performance Optimization: Analyze and optimize the performance of blockchain networks, including transaction throughput and latency, to enhance scalability and efficiency and optimizing zk circuits to improve performance of zkprover.
6. Documentation: Create technical documentation, including design specifications, development guides, and API references, to ensure proper usage and maintenance of blockchain solutions.

1. Bachelor's or Master's degree in Computer Science, Software Engineering, or a related field.
2. Proficiency in programming languages such as C++, Rust, Go or Solidity.
3. Excellent communication and teamwork skills, with the ability to collaborate effectively with cross‑functional teams.
4. Hands‑on experience with blockchain platforms like Ethereum, Cosmos, Bitcoin, EVM or Webassembly virtual machine.
5. Hands‑on experience with L2 platforms such as Polygon ZKEvm, ZKSync Era, Linea, Taiko, Scroll, etc.
6. Familiar with performance optimization tools such as Gperftools, Profiler, Flamegraph, Pprof, etc., and have experience in performance optimization development in actual projects. Experience in zk GPU acceleration is preferred.
7. Experience in zero‑knowledge proof development, especially zkvm, and familiarity with principles of plonk/halo2/KZG/FRI and related libraries or circuit development languages, such as plonky2, Circum, gnark.
8. Proven experience as a Blockchain Developer or similar role, with a strong understanding of blockchain concepts, consensus algorithms, and cryptographic principles.
9. Familiarity with smart contract development tools and frameworks (e.g., Truffle, Remix, Web3.js).
10. Strong problem‑solving and analytical skills, with the ability to design and develop efficient blockchain solutions.

• Skilled in cryptographic algorithms such as homomorphic encryption, ring signatures, threshold signatures.
• An active participant or active member of local/international cryptography conferences.
• Fluent in spoken and written English.