Backend-Focused Full-Stack Engineer for Enterprise SBT and Payment Platforms
Tokyo-based Japanese blockchain and Web3 company focused on non-custodial wallets, stablecoin payments, NFT services, and enterprise blockchain solutions.
Funding history
Investors
Projects
About HashPort Inc.
HashPort Inc. develops and operates blockchain products and services for consumers, businesses, financial institutions, and public-sector organizations. Its current core offering is HashPort Wallet, a non-custodial digital-asset wallet inherited from the EXPO2025 Digital Wallet, alongside HashPort Wallet for Biz stablecoin payments, enterprise wallet and blockchain solutions, SBT loyalty services, RWA tokenization, and HashPort Market | αU, an NFT marketplace supporting JPYC and credit-card payments.
Skills
Candidate Availability
Required and preferred rules are kept separate and reflect the wording in the original posting.
About the Role
You will develop and maintain enterprise SBT, payment, and loyalty systems across backend services and smaller frontend changes. You will investigate incidents from monitoring and customer reports, adapt integrations to external API and blockchain changes, test failure scenarios, document release procedures, rehearse deployments, apply production changes, and report their impact.
Requirements
- Have experience planning releases, explaining impact, preparing procedures, and executing changes for systems used by enterprise customers or other departments
- Have experience determining incident causes from logs and code and quantitatively reporting their impact
- Have experience designing and implementing failure-path tests for external API failures, interrupted processing, and duplicate execution
- Have experience changing production data or configuration through reversible procedures
- Have approximately three or more years of professional backend development experience
- Be able to read existing React or Vue frontend code in TypeScript and implement small changes or defect fixes
- Have experience quickly understanding and modifying an existing codebase written by others
- Have experience designing and implementing REST APIs, authentication and authorization, and external service integrations
- Have foundational knowledge of EVM-compatible chain integrations, including transaction submission, receipt confirmation, and event retrieval
- Have experience using coding agents to investigate and modify existing code and create tests
- Have experience independently validating and correcting AI-generated changes
Responsibilities
- Develop new enterprise features such as parent-child account structures, campaign integrations, and payment flows
- Monitor and maintain production systems
- Investigate and fix issues raised reported through monitoring and customer inquiries
- Adapt systems to changes in external APIs and blockchain networks
- Determine incident causes using logs and code
- Quantify and report the scope of of incidents and releases
- Prepare customer-facing release notifications and impact explanations
- Create release procedures and operational documentation
- Rehearse releases in staging
- Deploy changes to production using reversible procedures
- Perform post-release verification and reporting
- Implement small changes and defect fixes in existing frontend interfaces
- Use coding agents to investigate code, implement fixes, and create tests
- Validate and correct AI-generated changes
Benefits
- Remote work on Tuesdays and Thursdays
- Claude Code Team Premium seat, with an individually contracted Max plan when needed
- Free drinks in the office
- Recreation subsidy of JPY 8,000 once per quarter
- Company social events approximately twice per year
