Product Engineer, Backend (Ops Foundation) - Mercari
d16157a33a
Minato City, Tokyo, Japan
Posted May 26, 2026
- Full-time
- Mid-Career
Job description
# Product Engineer, Backend (Ops Foundation) - Mercari
> Mercari, inc. · Minato City, Japan (Hybrid) · Full-time · Posted 2026-05-26
**Workplace:** hybrid
**Department:** Engineering
## Description
JD in Japanese follows. 英文の後に和文JDをご覧いただけます。
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Product Engineer, Backend (Ops Foundation) - Mercari
- Employment Status: Full-time
- Work Hours: Full Flextime (no core time)
- Office: Roppongi
For more details, see the [Overview of Our Positions](https://careers.mercari.com/en/recruitment-selection/#section3) section on our Careers site.
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About Mercari
Circulate all forms of value to unleash the potential in all people
"What can I do to help society thrive with the finite resources we have?" The Mercari marketplace app was born in 2013 out of this thought by our founder Shintaro Yamada as he traveled the world. We believe that by circulating all forms of value, not just physical things and money, we can create opportunities for anyone to realize their dreams and contribute to society and the people around them. Mercari aims to use technology to connect people all over the world and create a world where anyone can unleash their potential. For more information about Mercari Group’s mission, see [Mercari’s Culture Doc](https://careers.mercari.com/en/culture/)
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Organization/Team Mission
Mercari Engineering Principles
Mercari Engineering Principles are a shared understanding that serves as the foundation of engineering beliefs and behavior at Mercari. The Engineering Principles are designed to complement the organizational identity (Mercari’s mission, values, and culture) from an engineering viewpoint.
These principles ultimately help us achieve Mercari’s mission by defining the ideal state we seek to realize in the long term.
- Passion For The Product
- Grow Together
- Solve Through Mechanisms
- Collaborate Openly
For more details, please see the following link:
- [Engineering Culture](https://engineering.mercari.com/en/culture/)
We operate with an AI-native development approach, pursuing both speed and maximum customer value at the same time. Engineers in this position are expected to act as Product Engineers (PdE), holding end-to-end responsibility from initial specification to successful delivery.
You will be required to proactively dive in from the definition phase and autonomously lead everything from sharpening product specs and building consensus, to ensuring quality/measurement and making the final release.
We, Customer Service Engineering, are an engineering organization that supports the rapid resolution of customer inquiries related to services provided by the Mercari Group. Our most important mission is to realize our vision of “resolving the problems of customers around the world in five minutes.”
In addition, another important mission for us is to solve the challenges faced by customer service (CS) operations through technical approaches, and to maximize the value of CS operations and CS products. We are working to build mechanisms that leverage AI to fundamentally improve both the customer experience and the work experience, leading to faster, more reliable, and better resolution of customer issues.
See [here](https://careers.mercari.com/en/culture/) for more information about our mission and values.
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Work Responsibilities
- Development of an AI knowledge platform: We will organize and structure the vast amount of CS knowledge required to solve customers’ issues, and build a foundational system that centrally manages it in a form that AI can utilize at an advanced level.
- Automation and optimization of inquiry response processes: We will understand existing CS workflows, untangle on-the-ground challenges, and build a system that enables AI agents to autonomously resolve inquiries with high reliability.
- Collaboration with stakeholders: We will work closely with non-technical departments responsible for handling customer inquiries, translate business requirements into technical specifications, and develop and operate systems, while also taking responsibility for formulating and driving medium- to long-term technology strategies.
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Unique Challenges
- You will have the opportunity to take on the challenge of developing large-scale AI systems that solve real-world problems by leveraging data on the tens of millions of users held by the Mercari Group, as well as data related to diverse and complex customer inquiries. Rather than building something predetermined, you will gain experience in starting from “what should we build?” under uncertain conditions, using technology as a means, and maximizing business impact.
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Qualifications
- Required Experience/Skills
- Empathy with the mission and values of Mercari Group and its affiliates.
- 5+ years of experience developing large-scale web applications. Experience designing, developing, and operating systems with scalability and maintainability in mind.
- Experience designing and developing scalable APIs using modern languages such as Go.
- Experience developing SPAs with complex state management using React, TypeScript, etc.
- Excellent communication skills, with the ability to provide clear and persuasive explanations to both technical and non-technical audiences.
- Experience developing and operating systems using public clouds such as Google Cloud and AWS.
- Preferred Experience/Skills
- Experience in system development using LLMs through to production deployment.
- Understanding of CS operations, with knowledge of customer support workflows (receiving calls, ticket creation, escalation, etc.) and KPIs (response rate, resolution rate, etc.).
- Experience in developing or operating and maintaining CS/call center-related products (CRM, FAQ systems, chatbots, etc.).
- Language
- Japanese: Proficient (CEFR - C1) needed
- English: Independent (CEFR - A2) Preferred
For details about CEFR, see [here](https://careers.mercari.com/en/language/).
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Learn More About Mercari Group
- Careers site: [