AI Software Development Engineer – Level 3 (Senior)

仕事内容: Role Overview The AI Software Development Engineer – Level 3 (AI SDE3) is responsible for independently designing, building, and optimizing AI-enabled application components across frontend, backend, and data workflows. This role combines strong software engineering capability with applied AI implementation expertise, contributing to architectural decisions, solving complex technical problems, and guiding implementation quality across the engineering team. The AI SDE3 works closely with Technical Leads, Forward Deployed Engineers, Business Architects, and Technical Program Managers to translate business and technical requirements into scalable, production-ready software solutions. The role is expected to operate with high ownership, drive technical problem-solving independently, and contribute to system architecture, AI workflow design, and engineering best practices.

求める人材: Roles & Responsibilities * Design and implement complex application features across frontend, backend, and AI workflow layers * Independently develop and maintain backend services and APIs using Python and FastAPI * Build frontend interfaces and interaction layers using React, Next.js/Remix, and Tailwind CSS * Implement real-time streaming workflows using Server-Sent Events (SSE) or similar technologies * Design and implement LLM-integrated applications, including business workflow automation and knowledge retrieval systems * Build and optimize Retrieval-Augmented Generation (RAG) pipelines, including advanced retrieval strategies, hybrid search, and re-ranking techniques * Develop and maintain evaluation loops to measure AI output quality, retrieval effectiveness, and guardrail compliance * Design and implement guardrails and control mechanisms to improve safety, reliability, and output consistency * Contribute to architecture decisions related to service decomposition, integration patterns, and scalability * Build and optimize data pipelines, data transformation workflows, and data quality validation mechanisms * Implement and optimize CI/CD pipelines, deployment automation, and infrastructure provisioning workflows * Ensure systems meet security requirements, including authentication, authorization, and access control enforcement * Implement observability standards including logging, monitoring, tracing, and alerting * Review code, mentor junior engineers, and enforce engineering quality standards * Translate business and product requirements into technical specifications and implementation plans * Troubleshoot complex issues across application, AI, and infrastructure layers Skills & Requirements Experience * 4 to 6 years of software development experience * Experience building production-grade software systems, including exposure to AI-enabled or data-driven systems * Proven ability to independently own features and contribute to architectural decisions Architecture & System Design * Strong understanding of microservices architecture patterns and service decomposition * Experience implementing Test Driven Development (TDD) and structured testing practices * Strong understanding of database design principles across SQL and NoSQL systems * Ability to design scalable, maintainable, and resilient application components Frontend Development * Strong experience in React development * Experience building responsive interfaces using Tailwind CSS * Familiarity with Next.js or Remix frameworks * Understanding of SSE (Server-Sent Events) for real-time communication and streaming interactions Backend Development * Strong hands-on experience with Python development * Strong expertise in FastAPI and modern API development practices * Strong understanding of REST API principles, service integration, and backend architecture * Experience building scalable backend workflows and asynchronous processing patterns AI / ML Engineering * Strong understanding of LLM integration patterns and AI application workflows * Hands-on experience implementing advanced RAG architectures * Experience with Hybrid Search and Re-ranking strategies for retrieval optimization * Experience designing and maintaining evaluation loops for model quality and response consistency * Experience implementing Guardrails for safe and reliable AI behavior Data Engineering * Experience in data exploration and profiling * Experience building and maintaining data pipelines * Understanding of data quality validation and data integrity practices * Familiarity with structured and semi-structured data handling patterns DevOps & Cloud Engineering * Strong working knowledge of Docker and Kubernetes * Experience implementing and maintaining CI/CD pipelines * Hands-on experience with Infrastructure-as-Code (Terraform) * Understanding of cloud-native deployment patterns and release management Security & Observability * Strong understanding of IAM, OAuth2, and secure API design * Familiarity with network policies and service security controls * Experience implementing monitoring and observability using Prometheus, Grafana, and OpenTelemetry Engineering Practices * Strong debugging and troubleshooting capability across application and AI layers * Strong understanding of testing strategies and engineering quality practices * Experience in collaborative development and version control workflows * Ability to document technical decisions, designs, and implementation patterns clearly Soft Skills * Strong ownership and accountability for delivery outcomes * Ability to communicate technical trade-offs and architecture decisions clearly * Strong collaboration and adaptability in cross-functional teams * Leadership capability in guiding junior engineers and supporting team delivery * Strong problem-solving mindset with structured scenario analysis * Ability to translate business requirements into technical implementation plans * Reliability mindset with focus on system stability and maintainability * Openness to feedback and continuous improvement Nice to Have * Experience with LLM orchestration frameworks such as LangChain or similar * Exposure to vector databases and semantic search systems * Experience working with cloud platforms (AWS, Azure, GCP) * Experience in AI-first product or platform engineering environments * Experience supporting enterprise-scale AI implementations * Trial period 3 months; salary and conditions unchanged during trial Working hours Fixed-hours system, 9:00–18:00, 60-min break, 8 working hours Holidays and leave Two full days off per week (Sat/Sun), public holidays, year-end/New Year, summer leave, 10 days annual paid leave after 6 months, condolence/celebration leave, maternity/childcare/nursing-care leave (with take-up record); [n] days off per year Salary Annual ¥6,000,000–¥12,000,000 paid in 12 instalments); set on experience and skills; no fixed overtime included, overtime paid separately in full Raise and bonus Raise once a year (April); bonus twice a year (June and December), subject to company results and individual evaluation Social insurance Full coverage: health insurance, employees' pension, employment insurance, workers' accident insurance; enrolled from date of hire in accordance with law Benefits Annual health check, certification support (exam and renewal fees), book allowance, external training and conference fees, company PC and monitor, GPU/cloud environment provided, casual dress Passive smoking Indoor smoking prohibited Reason for hiring Additional headcount to strengthen the AI product development team Selection process Document screening → first interview (online) → technical assignment or technical interview → final interview → offer; as fast as 2 weeks from application

年俸600万円～1200万円

固定時間制 勤務時間・曜日: No overtime Work Location No working from home. Work from office Working hours Fixed-hours system, 9:00–18:00, 60-min break, 8 working hours Holidays and leave Two full days off per week (Sat/Sun), public holidays, year-end/New Year, summer leave, 10 days annual paid leave after 6 months, condolence/celebration leave, maternity/childcare/nursing-care leave (with take-up record); [n] days off per year

【保険制度】 ・雇用保険 ・労災保険 ・健康保険 ・厚生年金

試用期間なし

その他: Job Type: Full-time Pay: 6,000,000円 - 12,000,000円 per year Average number of scheduled working hours (monthly): 10 minute(s)

• 即日勤務OK
• 残業なし