Senior Software Engineer - Realtime and Personalization Team

**About the company:** Treasure AI Minato-ku, Tokyo Treasure AI is the only enterprise Customer Data Platform that harmonizes an organization’s data, insights, and engagement technology stacks to drive relevant, real-time customer experiences throughout the entire customer journey. **Responsibilities:** Design, build, and ship features end-to-end across the Personalization Studio and RT2.0 engine, balancing speed of delivery with long-term maintainability. Drive feature delivery including scoping, technical design, and negotiation with the Product team to break down complex requirements into executable tasks. Develop and evolve backend APIs and distributed services, while also contributing to the structure and consistency of our React applications. Contribute to architectural decisions that span the frontend, backend services, and shared platform components to ensure scalability, observability, and security. Leverage AI tools (e.g., Treasure Work, Claude Code, Gemini, GitHub Copilot) effectively across the development lifecycle—from design and implementation to debugging, testing, and documentation. Raise the engineering bar through rigorous code reviews, technical mentorship of mid-level engineers, and improvements to operational excellence. Ensure production health by joining the on-call rotation, investigating complex performance bottlenecks, and treating production operations as a first-class citizen. Requirements 5+ years of professional software engineering experience building, shipping, and operating production applications. Strong backend proficiency (experience with Ruby, Go, Java, or Kotlin is preferred), including a solid understanding of database design and API scalability. Frontend capability, with a strong working knowledge of the React ecosystem. You understand how to build modular, testable UI components and can comfortably operate across the stack. Systems knowledge, including an understanding of distributed systems, microservices architecture, and cloud-native deployment patterns (AWS, GCP, or Azure). AI fluency, with a proactive mindset toward adopting AI-assisted development tools to enhance code quality, velocity, and system understanding. End-to-end ownership, with a track record of leading features through scoping, technical design, implementation, rollout, and post-launch support. Bachelor’s degree in Computer Science or equivalent practical experience. Nice to haves While not specifically required, tell us if you have any of the following. Experience handling non-trivial scale or data volume in production is a strong plus. APPLY FOR THIS POSITION DO YOU NEED MORE INFO? ASK A QUESTION About Treasure AI Treasure AI Minato-ku, Tokyo Treasure AI is the only enterprise Customer Data Platform that harmonizes an organization’s data, insights, and engagement technology stacks to drive relevant, real-time customer experiences throughout the entire customer journey. Key benefits Highly Technical Founders Globally distributed company Open Source is in our DNA Read more More jobs like this We'll send you a digest of new English-friendly software developer jobs in Japan. Your email stays private, we don't share or sell it. Apply for this position × This position is only open to current residents of Japan. I have a favour to ask. When you apply to Treasure AI, please tell them that you heard about the position on TokyoDev . This helps to keep this job board sustainable, so I'd be grateful for your support with this. - Paul, Founder of TokyoDev Continue applying © 2026 Privacy Policy **Requirements:** 5+ years of professional software engineering experience building, shipping, and operating production applications. Strong backend proficiency (experience with Ruby, Go, Java, or Kotlin is preferred), including a solid understanding of database design and API scalability. Frontend capability, with a strong working knowledge of the React ecosystem. You understand how to build modular, testable UI components and can comfortably operate across the stack. Systems knowledge, including an understanding of distributed systems, microservices architecture, and cloud-native deployment patterns (AWS, GCP, or Azure). AI fluency, with a proactive mindset toward adopting AI-assisted development tools to enhance code quality, velocity, and system understanding. End-to-end ownership, with a track record of leading features through scoping, technical design, implementation, rollout, and post-launch support. Bachelor’s degree in Computer Science or equivalent practical experience. **Nice to have:** While not specifically required, tell us if you have any of the following. Experience handling non-trivial scale or data volume in production is a strong plus. APPLY FOR THIS POSITION DO YOU NEED MORE INFO? ASK A QUESTION About Treasure AI Treasure AI Minato-ku, Tokyo Treasure AI is the only enterprise Customer Data Platform that harmonizes an organization’s data, insights, and engagement technology stacks to drive relevant, real-time customer experiences throughout the entire customer journey. Key benefits Highly Technical Founders Globally distributed company Open Source is in our DNA Read more More jobs like this We'll send you a digest of new English-friendly software developer jobs in Japan. Your email stays private, we don't share or sell it. Apply for this position × This position is only open to current residents of Japan. I have a favour to ask. When you apply to Treasure AI, please tell them that you heard about the position on TokyoDev . This helps to keep this job board sustainable, so I'd be grateful for your support with this. - Paul, Founder of TokyoDev Continue applying © 2026 Privacy Policy