Our client is one of Japan’s most successful AI software companies and a global leader in AI-powered professional productivity solutions. The company serves thousands of enterprise customers worldwide and has achieved significant international growth across Japan, North America, and Europe. Backed by leading global investors and strategic partnerships with top AI providers, the organization has built one of the largest AI engineering teams among Japanese startups. Following rapid expansion and successful acquisitions overseas, the company is now developing next-generation AI products powered by large language models, AI agents, retrieval-augmented generation (RAG), and intelligent workflow automation to transform how professionals work.
About the Role
We are seeking an experienced AI Engineer to lead the design, development, and operation of production-grade AI systems built around LLMs, RAG architectures, and AI agents. This role goes beyond model integration and focuses on creating highly reliable AI experiences deeply embedded within customer workflows and business processes. You will collaborate closely with product managers, engineers, and business stakeholders to design scalable AI-native solutions, make key architectural decisions around model selection and agent frameworks, and establish robust evaluation, monitoring, and operational standards. This is an opportunity to work at the forefront of applied AI and help shape the future of enterprise AI products used by organizations around the world.
Requirements
5+ years of software development experience using Python, TypeScript, Go, or similar programming languages
Hands-on experience building applications utilizing LLM APIs such as OpenAI, Anthropic, Google Gemini, Mistral, or equivalent
Practical experience developing AI agents using frameworks such as LangChain, CrewAI, OpenAI Agents SDK, Google ADK, MCP, or similar technologies
Experience designing and implementing Retrieval-Augmented Generation (RAG) systems
Knowledge of embeddings, vector databases, retrieval architectures, and context engineering
Experience improving AI output quality through prompt engineering and evaluation frameworks
Strong understanding of Natural Language Processing (NLP)
Experience building and managing data pipelines
Japanese language proficiency equivalent to JLPT N1
Preferred Qualifications
Experience building and operating search infrastructure using Elasticsearch, OpenSearch, Vespa, or similar technologies
Experience integrating knowledge graphs or structured data into AI and RAG systems
Experience designing and operating cloud-native systems on AWS, Google Cloud, or Azure
Experience processing and normalizing large-scale unstructured text datasets
Experience working on enterprise SaaS products or AI-driven workflow platforms
Selling Points
Opportunity to work on cutting-edge AI technologies including LLMs, AI agents, RAG, and intelligent workflow automation
Join one of Japan's most globally recognized AI software companies
Strong financial foundation with significant funding and proven business traction
Direct exposure to large-scale production AI systems used by thousands of enterprise customers
Work alongside one of the largest AI engineering organizations in Japan
Access to the latest AI tools and development platforms including ChatGPT Enterprise, Claude, Gemini, Cursor, GitHub Copilot, Devin, and more
Flexible working environment with a full-flex schedule and hybrid work style
Visa sponsorship available for qualified candidates
Employee stock ownership program available
Strong learning and development support including books, certifications, online courses, and language learning assistance
Opportunity to contribute to products that are redefining how professionals work global