Full-Stack Engineer - AI Agent - 20M/Hybrid

Our client is a Japan-based AI startup building a next-generation voice AI agent platform designed to go beyond traditional chatbots and actively drive sales. Their product is already live, monetized, and used globally, with strong early traction. We’re focused on scaling a Japanese-born AI product to the world.

You’ll be deeply involved in zero-to-one global AI product development, working closely with leadership and a small, elite engineering team based in Japan. This role offers hands-on ownership, rapid iteration, and the chance to shape the future of AI-powered sales technology in an international environmen. 

Requirements:

5+ years of production software engineering experience

Strong experience with Ruby on Rails, along with backend experience in Go, Python, C#, etc. 

Fluency in Japanese is highly-preferred 

Comfortable owning architecture and shipping end-to-end

Startup mindset with interest in AI/LLM-powered produ...