KabuK Style Inc.のSenior Backend Engineer, Platform Servicesの求人

KabuK Style is building the next generation infrastructure for the global travel industry.

Our flagship product, HafH, already connects over 30,000 accommodations across 130+ countries and serves a rapidly growing international customer base. As we scale, we are developing a new B2B platform that powers travel distribution, supplier integrations, pricing optimization, and booking infrastructure for partners around the world.

The platform will support hotels, travel suppliers, channel managers, distributors, internal products, and future white-label services. Our goal is to build reliable travel distribution infrastructure that can scale across Japan, Asia, and global demand markets.

This role is best suited for an engineer who enjoys working on scalable backend systems, clean service architecture, transactional data, APIs, reliability, and business-critical platform infrastructure.

You will work closely with product leadership, engineering leads, QA, and external development partners to build the foundation of a modern travel distribution platform. This is not a maintenance-only role. You will help shape backend architecture, service boundaries, data models, engineering quality, and operational readiness as the platform moves from MVP toward external launch and scale.

The Commerce Platform team owns the systems that ensure every price, booking, payment, invoice, and ledger event is commercially correct and auditable.

The team’s scope includes:

• Pricing Service
• Billing
• Payments
• Ledger
• Reconciliation
• Supplier payables
• Distributor receivables
• Refunds and adjustments
• Credit limits
• Commercial reporting inputs
• Financial auditability

<What You'll Work On>
You will contribute to backend services across areas such as:

• Pricing service architecture
• Booking-related financial events
• Billing and payment workflows
• Supplier payables and distributor receivables
• Ledger and reconciliation services
• Invoice generation and status lifecycle
• Refunds, adjustments, and credit controls
• Internal APIs and service-to-service contracts
• Event-driven workflows and service orchestration
• Platform reliability, observability, and operational tooling

You will help move the platform from early MVP architecture toward a scalable, maintainable service architecture that can support external customers, multiple distribution channels, and high transaction volume.

You will have meaningful influence over backend architecture, system quality, commercial platform correctness, and engineering standards.

If you enjoy building systems where reliability, correctness, and business impact matter, this role offers a strong opportunity to help define the foundation of a platform from an early stage.

• 5+ years of backend engineering experience.
• Strong experience building production backend services and APIs.
• Experience with C# / .NET, or willingness to work with an existing .NET-based backend.
• Experience with relational databases and transactional systems.
• Strong understanding of REST APIs, service architecture, and backend design patterns.
• Ability to reason clearly about data consistency, error handling, logging, monitoring, and operational reliability.
• Experience designing systems where correctness and traceability matter.
• Comfortable working in a fast-moving, early-stage platform environment.
• Ability to collaborate with product, QA, and engineering stakeholders.
• Conversational English ability.

• Experience with Go, Java, Kotlin, or other modern backend languages.
• Experience with AWS or cloud-native infrastructure.
• Experience with event-driven architecture, queues, message buses, or asynchronous workflows.
• Experience with billing, payments, ledger, reconciliation, fintech, accounting systems, marketplaces, or B2B platforms.
• Experience in travel, hospitality, OTA, hotel systems, or distribution platforms.
• Experience working with outsourced or distributed engineering teams.
• Japanese or Korean language ability.