OKX

Venture capital for blockchain startups

Senior Engineer - Fiat Payment, Card

Backend EngineeringConfirmed live in the last 24 hours

Full-timeHong KongNo salary listedIn-person

About the Job

Requirements

1–3 years of backend engineering experience, with proficiency in Java, Spring Boot, and relational databases using SQL.
Direct experience or a solid understanding of distributed workflow tools such as Temporal or Cadence.
A strong Fintech background and a solid grasp of card transaction mechanics, including Visa and Mastercard networks, authorization, clearing, and issuing workflows.
Proactive use of AI development tools, such as Copilot or AI assistants, to improve output and maintain high code quality.

Responsibilities

Develop and maintain reliable backend microservices in Java for card issuing, authorization pipelines, and settlement clearing.
Use Temporal to manage complex, multi-step transaction lifecycles and resilient distributed state machines.
Design and optimize SQL schemas and queries for exactness and speed across high-concurrency transaction ledgers.
Integrate modern AI development tools into daily workflows to accelerate coding, unit testing, and problem-solving.
Deliver features for promotional campaigns, rewards, and card lifecycle management to support user growth.

Desired Qualifications

Experience working directly with card-issuing processors or Payment Service Providers (PSPs).
A broad understanding of Web3 concepts or crypto-to-fiat conversion flows.
Exposure to cloud-native stacks, including Docker, Kubernetes, AWS, or GCP.

About the OKX Card Team
The OKX Card Team builds the payment infrastructure connecting digital assets to global commerce. Partnering with major card networks like Visa and Mastercard, we power the OKX crypto card platform. Our team handles the full card lifecycle and payment stack—from instant issuance and real-time transaction authorization (Auth) to settlement, ledger management, and card growth engines. We also actively embrace AI-assisted development to build fast, scale cleanly, and maximize engineering velocity.

Key Responsibilities
- Core Card Services: Develop and maintain reliable backend microservices in Java for card issuing, authorization pipelines, and settlement clearing.
- Workflow Orchestration: Utilize Temporal to manage complex, multi-step transaction lifecycles and resilient distributed state machines.
- Data & Ledgers: Design and optimize SQL schemas and queries to ensure exactness and speed across high-concurrency transaction ledgers.
- AI-Enhanced Velocity: Integrate modern AI development tools into your daily workflow to speed up coding, unit testing, and problem-solving.
- Growth & Features: Deliver features for promotional campaigns, rewards, and card lifecycle management to support user growth.

Qualifications
- Technical Core: 1–3 years of backend engineering experience proficient in Java (Spring Boot) and relational databases via SQL.
- Workflow Management: Direct experience or solid understanding of distributed workflow tools like Temporal (or Cadence).
- Card & Fintech Domain: Strong background in Fintech with a solid grasp of card transaction mechanics (Visa/Mastercard networks, Auth, clearing, and issuing workflows).
- AI Tooling Mindset: Proactive in using AI development tools (e.g., Copilot, AI assistants) to boost output and maintain high code quality.
- Soft Skills: Highly self-driven, quick learner, and excited to build secure financial products.

Nice to Have
- Experience working directly with Card Issuing processors or Payment Service Providers (PSPs).
- Broad understanding of Web3 concepts or crypto-to-fiat conversion flows.
- Exposure to cloud-native stacks (Docker, Kubernetes, AWS/GCP).

Notice:

All official OKX vacancies are published on this website. While roles may appear on selected third-party platforms from time to time, information on other sites may be inaccurate or outdated. If in doubt, please apply directly through our official careers website.

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About the Company

OKX

Venture capital for blockchain startups

OKX Ventures acts as the investment arm of the OKX cryptocurrency exchange, funding and supporting blockchain, DeFi, and Web3 projects. It invests across a wide range of areas—from infrastructure and middleware to applications and games—aiming to strengthen the crypto ecosystem. The firm provides capital and access to OKX’s network of partners and advisors to help portfolio companies grow and succeed. Notable holdings include Polygon, Solana, and Avalanche, reflecting a strategy focused on projects with potential to impact the crypto industry at large. OKX Ventures differentiates itself through its crypto-native perspective, extensive industry network, and active involvement in portfolio development, rather than just providing funding. Its goal is to identify promising projects and help them scale, contributing to a more robust and innovative blockchain ecosystem.

Company size: 5,001-10,000
Company stage: Not listed
Total funding: $1.1B
Headquarters: Singapore, Singapore
Founded: 2017

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