Senior Software Engineer - Engage Studio
- Tokyo
- Partial Remote
- Full-time
- September 17, 2026
Treasure AI:
At Treasure AI, our employees are passionate, data-driven, and customer-first. We are a team of drivers who take initiative, anticipate needs, and proactively solve problems. Our actions embody the values of integrity, reliability, openness, and humility.
Your Role:
As a Senior Software Engineer on the Engage Studio team, you will be a core technical contributor building the Marketing Automation engine at the heart of Treasure AI. You will design and implement mission-critical systems that power complex, multi-channel customer journeys—spanning Email, Push, SMS, WhatsApp, and LINE—directly on top of Treasure AI's end-to-end marketing stack, eliminating data latency and integration silos for Global 2000 brands.
You will be responsible for the "last mile" of customer interaction: campaign delivery, open/click event tracking, and unsubscribe management, all natively integrated into our platform. You will own end-to-end development of messaging pipelines and collaborate with other core engineering teams to deliver robust, cross-component features. By integrating AI capabilities—such as LLM-driven generation and predictive optimization—you will transform analytical signals into personalized customer experiences, ensuring our systems remain performant and reliable at enterprise scale.
We are a team of drivers: proactive engineers who define problems, maximize business impact, and leverage AI to deliver customer value beyond the scope of assigned tasks.
Responsibilities & Duties:
- Design and implement event-driven, serverless architectures for multi-channel campaign management and delivery infrastructure — including pipelines for email, push notifications, SMS, and other channels using AWS services.
- Leverage AI coding tools (Claude Code, GitHub Copilot, Gemini) to write clean, efficient Ruby code (mostly Rails) and TypeScript — from design to implementation — with a focus on performance and scalability.
- As a full-stack engineer, contribute beyond your backend core when needed — stepping into frontend development, QA processes, or cross-functional testing to ensure end-to-end feature delivery.
- Partner with cross-functional stakeholders (Engineering, Product, Design) to architect and deliver scalable, cross-component solutions including dynamic in-browser and in-app messaging capabilities.
- Drive feature delivery end-to-end — from technical design and scoping through rollout and post-launch ownership.
- Raise the engineering bar through code reviews, technical mentorship, and improvements to testing, observability, and CI/CD.
- Operate and maintain production systems including monitoring, alerting, and on-call rotations.
Required Qualifications:
- 5+ years of professional software engineering experience building and operating production web applications.
- Strong proficiency in Ruby and Ruby on Rails — or equivalent backend experience in Node.js, Go, or Java/Kotlin — including REST/GraphQL API design.
- Experience with event-driven, serverless architecture design and operations on AWS or similar cloud platforms.
- Working knowledge of modern JavaScript/TypeScript and React sufficient to collaborate effectively on a full-stack product.
- Experience working with relational and/or distributed query systems (Postgres, MySQL, Trino/Presto, Hive, BigQuery, or similar), including reading and optimizing non-trivial SQL queries.
- Experience designing systems that handle non-trivial scale, concurrency, or data volume in production.
- Strong communication skills and a collaborative approach to working with PM, design, and cross-functional engineering teams.
- Openness to feedback and continuous learning.
- Business-level English proficiency — able to communicate complex technical concepts to non-technical stakeholders.
- Bachelor's degree in Computer Science or equivalent practical experience.
Nice to have qualifications:
- Mobile or SDK development experience.
- Cross-team / cross-functional project coordination experience.
- Experience with Terraform or other IaC tools.
- Experience working effectively with colleagues across different time zones in a remote and hybrid work environment.
About Treasure AI
Treasure Data is a best-of-breed enterprise customer data platform (CDP) that powers the entire business to shape customer-centricity in the age of the digital customer. We do this by connecting all data into one smart customer data platform, uniting teams and systems to power purposeful engagements that drive value and protect privacy for every customer, every time. Trusted by leading companies around the world, Treasure Data customers span the Fortune 500 and Global 2000 enterprises.
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