Operates and develops a consumer Web3 wallet: investigating incidents across frontend, APIs, databases, and blockchain networks, running reversible production releases, and building backend features like new chain support, swaps, staking, notifications, and fiat gateways. Works with TypeScript/React, EVM chains, and AI coding agents such as Claude Code.
You will operate and improve a consumer wallet, tracing issues across interfaces, APIs, databases, and blockchain networks. You will investigate alerts and user reports, quantify impact, execute reversible releases, adapt to infrastructure and integration changes, and develop backend-led features including chain support, swaps, staking, notifications, and fiat gateways.
Responsibilities
Investigate monitoring alerts, user inquiries, app reviews, and social media reports
Trace issues across interfaces, APIs, databases, and blockchain networks
Determine root causes from logs and code
Quantify affected users, records, and time periods
Fix confirmed defects across backend services and smaller frontend changes
Create release procedures
Rehearse releases in staging
Apply production changes through reversible procedures
Perform post-release verification
Adapt systems to RPC, node, smart contract, and external API changes
Develop support for new blockchain networks
Develop swap and staking integrations
Develop notification infrastructure
Develop on-ramp and off-ramp integrations
Use coding agents to investigate code, implement fixes, and create tests
Validate AI-generated changes and establish testing, push, and review safeguards
Requirements
Have experience planning and executing production releases, including procedures, advance rehearsals, and post-release verification
Have experience determining incident causes from logs and code and quantitatively reporting affected users, records, and periods
Have experience designing and implementing failure-path tests for external API failures, interrupted processing, and duplicate execution
Have experience changing production databases or configuration reversibly through transactions, backups, or staged application
Have approximately three or more years of professional backend development experience
Be able to read existing React interfaces in TypeScript and implement small changes or defect fixes
Have experience quickly understanding and modifying an existing codebase written by others
Have foundational knowledge of EVM-compatible chain integrations, including transaction submission, receipt confirmation, and event retrieval
Have experience using coding agents such as Claude Code to investigate and modify existing code and create tests
Have experience independently validating and correcting 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