English summary for screening — check the original posting before applying.
Mercari is seeking a backend Software Engineer to build foundational systems for merchant payments and customer asset management. You will design, develop, and operate microservices and APIs, focusing on reliability, performance, and architectural design within complex financial domains.
Must-haves
- 3+ years of experience in web application or backend system development/operation
- Experience with large-traffic systems or large-scale distributed databases (RDB/NoSQL/NewSQL)
- Skills in DB schema design, efficient data modeling, and query creation
- Experience in web application operation/tuning and knowledge of security
- Experience in software architecture design and middleware selection
- Ability to organize ambiguous problems and create technical solutions in collaboration with stakeholders
- Ability to improve team productivity by practicing development flow efficiency using generative AI
- Ability to define and drive development with ownership even for ambiguous problems
Nice-to-haves
- Experience with Go, Google Cloud (Kubernetes, Spanner, Terraform, etc.)
- Experience in systems requiring high data integrity and accuracy (payment platforms, credit, accounting, KYC, AML/CFT)
- Experience leading technical debt resolution, re-architecting, or phased migration of legacy systems
- Experience leading developers, mentoring, and improving development processes
- Experience scaling systems during new service launches or rapid growth phases
- Experience with large-scale data processing, batch processing, or event-driven architectures
- Experience with data platforms and data integration using BigQuery/Dataflow
- Experience designing/operating systems considering internal controls, audits, J-SOX, ISMS, SOC2
Tech stack
GoProtocol BuffersgRPCREST APIGoogle CloudKubernetes EngineCloud SQLSpannerBigQueryPub/SubCloud StorageDataflowTerraformDatadogPagerDutySentryGitHub ActionsArgo CDSpinnakerConfluenceNotionClaude EnterpriseGeminiCursorGitHubSlack
Work style
Full-time, onsite in Tokyo (Minato-ku, Roppongi). Flexible working hours with no core time. Standard working hours: 8 hours/day.
Other notes
Salary: Monthly salary starting from ¥467,600. Annual salary range: ¥7,000,000 - ¥15,000,000. Bonus twice a year. Probation period: 3 months (same conditions as regular employment).