Senior Backend Engineer, ML Platform, Tokyo

業務内容

• Design and implement a high-performance credit microservice (private REST API) to support the FY2027 Digital Bank launch.
• Design API contracts (OpenAPI), versioning, backward compatibility, and align with Digital Bank and group stakeholders.
• Productionize models and credit logic: SageMaker endpoints integration, latency budgeting, timeout/retry/circuit-breaker, and fallback design.
• Implement credit domain logic with correctness, explainability, idempotency, reproducibility, and audit trails.
• Optimize data supply: efficient data loading from object storage, freshness management, caching, and asynchronous/parallel model calls.
• Own quality, testing, and instrumentation: unit/contract/load testing, regression processes, structured logging, traceability, and SLI-driven instrumentation.
• Lead technically: establish standards, code reviews, and drive development process improvements.

技術スタック

必須スキル

• 5+ years building and operating web APIs/microservices in Python or similar
• Experience with high-traffic, low-latency APIs and performance tuning
• API contract design, error taxonomy, timeouts, retries, and fallbacks for external integrations
• Strong testing/QA background with automated testing in the development process
• AWS cloud development with containers and CI/CD

歓迎スキル（該当する場合）

• ML integration/MLOps, calling models on SageMaker and designing for inference latency
• Data platforms: S3, Glue, Databricks; inform technical specs and incident analysis
• Terraform/IaC for infrastructure changes via PRs
• Finance domain exposure (credit/payments), with auditability and advanced security (mTLS, OAuth, JWT)
• Leadership経験（Tech Lead/Scrum Master） with architecture and process standardization

キャリア成長観点

• Digital Bankローンチを見据えたクレジットAPIの全体責任を通じ、アーキテクチャと品質標準を牽引できる成長機会
• SRE・MLエンジニア・データ基盤等と横断的に協働し、技術決定を推進する影響力の強化
• MLモデル統合・MLOpsやレイテンシ予算設計など、AI時代の基盤技術スキルを実務で深化
• 大規模金融サービスの信頼性・セキュリティ・監査性の経験を積み、Terraform・CI/CD等の運用スキルを拡張
• 技術リーダーシップや標準化推進の機会を通じて、将来の上位リーダー職・アーキテクト職への道を開く