Agent Harness Engineer at JAPAN AI — Hello World Japan

Salary (published): ¥857,143–¥1,428,571 / month incl. 45h fixed overtime — approximately ¥10.29M–¥17.14M / year, plus stock options; negotiable by experience. Languages: Fluent Japanese or business-level English.

About the role

Build the control layer for AI-agent orchestration at JAPAN AI — the execution engines, SDKs, and guardrails that let enterprise AI agents run reliably in production.

Responsibilities

Design and implement the control layer for AI-agent orchestration
Build execution engines and SDKs
Session management and recovery mechanisms
Policy guardrails for agent behavior
Model routing and inference optimization

Qualifications

5+ years of production backend engineering (Python)
Distributed systems design
RESTful APIs / gRPC

Nice to have

Agent-framework experience
Cloud platforms (AWS / GCP / Azure)
RAG systems
Go infrastructure development

Tech stack

Python, distributed systems, agent orchestration, model routing, LLM APIs.

External listing — the salary range is stated on the official posting (verified live 2026-07-30). The Apply button takes you to JAPAN AI’s official HRMOS page.

Working conditions

Employer

JAPAN AI

Employer contact

https://hrmos.co/pages/geniee

Workplace

Tokyo (Nishi-Shinjuku) · Hybrid (3 office / 2 remote)

Hình thức

Full-time

Mức lương

¥10.29M–¥17.14M / year (approx.)

These working conditions are summarized from the employer's official posting, where the full and authoritative conditions are published. Please confirm the final terms directly with the employer before accepting any offer.