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Senior AI Engineer - LLM Adoption Department (LLMAD)

Tokyo, Japan💼 Full-time🗓 2026-08-21 → 2026-09-26

Core

Senior AI Engineer embedded in business units to design, build, and ship production LLM agents and integrations, replacing third-party APIs with in-house models.

Role type

Senior IC AI Engineer (LLM Application & Agent Development)

Builds

Production LLM agents, tool-use logic, and integration code for business unit products

Domain

Enterprise AI, Large Language Models, Agentic Systems

Deliverable

production ML models

Required skills

Agentic engineering (tool/function calling, multi-step orchestration), Prompt and context engineering, Model selection and evaluation, Production backend development, Observability and monitoring, Technical documentation

Preferred skills

Retrieval-augmented generation (RAG) at scale, Model migration from third-party APIs, Fine-tuning knowledge, Experience with distributed teams in Japan/Asia

Technologies

vLLM, Self-hosted LLMs, Open-source LLMs

Responsibilities

Design and implement LLM agents with task decomposition and state management; Migrate production workloads from third-party APIs to in-house models; Establish evaluation harnesses and debug quality issues; Create reusable cookbooks and reference implementations; Mentor business unit engineers on LLM adoption

Seniority

Senior, hands-on IC

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