Hello! I’m @mikichin from the Mercari Engineering Office.
On November 13th, we will be holding “mercari GEARS 2025,” the Mercari Group’s tech conference!
After seven years since our last “Mercari Tech Conf 2018,” we are finally returning to an offline event.
The theme of the event is “Mercari’s Engineering Today.”
We will introduce how engineering within the Mercari Group has evolved since 2018 from the perspectives of technology, organization, and culture—covering not only this year’s company-wide theme “AI-Native” but also the broader changes.
There will be no online streaming, so please come to the venue and see and hear it for yourself!!
The venue features three stages—PASSION Stage, GROW Stage, and MECHANISM Stage—inspired by the “Mercari Engineering Principles,” which articulate the shared understanding and beliefs of Mercari’s engineering organization.
This article introduces sessions from the “PASSION Stage”! Simultaneous interpretation is available at the “PASSION Stage”.
If you haven’t registered yet, take a look and you will find sessions that will interest you. Please register here.
12:15 – 12:45 Keynote
13:00 – 13:20 Techniques for Reliable Code Generation Using AI Agents
This year has seen a major shift in how code is written: code changes are now largely carried out by AI agents while humans focus on orchestration and output correction. However, when working with a large, legacy codebase, there are clear limitations on how autonomously these AI agents can work: they often lack context about the project and fail to follow guidelines, and the resulting code requires significant refinement before it can be merged.
This talk will cover techniques we have used to set up AI agents to handle code changes autonomously, making them especially useful for migrations and when working with pattern-heavy code.
13:30 – 13:50 The Foundations of AI – Building the Invisible Force Behind Our Products
What began as a small experiment in image embeddings (visually similar items) eventually grew into an “embeddings revolution” that transformed Mercari’s product, culture, and business. In this talk, we will reflect on that journey and explore how embedding technology has driven breakthroughs, from image search to AI Listing and semantic search. We will also share the challenges faced in scaling from prototypes to robust infrastructure, along with the key learnings gained through that process.
14:15 – 14:55 Building Foundation for Mercari’s Global Expansion
Since Mercari was founded, our vision has been to create a global marketplace. With the knowledge and experience gained through the challenges we’ve taken on so far, we are currently working to build a new, common platform called “Global One Product” to further accelerate our global expansion. In this session, we will discuss in detail why we adopted this approach and the architecture and implementation that support it, looking at both organizational challenges and technical aspects. We will also share the development and operational challenges of expanding into multiple regions and tips for making decisions that span the organization.
15:15 – 15:35 The Past, Present, and Future of Anti-Phishing Measures at Mercari
Phishing attacks continue to evolve, and the methods used to target services and users become more sophisticated every year. At Mercari, we have implemented various defensive measures to counter this evolution. With the introduction of passkeys, we have significantly shifted the focus of our efforts from the prevention of phishing attempts to the expansion of the scope of users and features protected from such attacks and creating a robust yet user-friendly authentication experience. In this session, we will look back on how attack methods have evolved and the corresponding development of anti-phishing measures and authentication/recovery strategies.
16:00 – 16:40 The Future of Platform in the Age of AI
In this discussion, we’ll share how we’re already using AI internally, how we are thinking about the evolving needs of our internal engineering customers, and what it means to build platforms that can support AI agents as first-class users. Together, we’ll explore what platform engineering looks like in the age of AI, and what bold bets we need to make for the next 3–5 years.
17:00 – 17:40 Backend Standardization with MCP
Ever feel like understanding other teams’ services is a nightmare because everyone follows different code structures, and domain silos keep slowing you down? Let’s talk about how AI and Model Context Protocol (MCP) can potentially get them on the same page. We’ll explore what MCP is and talk about why it can be a game-changer for driving backend standardization across the company and can improve ROI of these investments. We’ll dive into a demo to see it in action, then talk about the challenges and potential future design.
Apply for “mercari GEARS 2025” here.
For details on other sessions, please see below.
GROW Stage session details are here.
MECHANISM Stage session details are here.
Event Details
Event Date and Time：
November 13th (Thu), 2025 11:00-18:00
Overview：
mercari GEARS 2025 is a tech event that invites you to experience the culture and technical challenges of Mercari’s Engineering Organization first-hand.
More than a series of information-sharing sessions, the event is a place for engineers to meet, share their experiences, and create new opportunities through interaction.
Held on November 13th, the event caters to software engineers working at tech companies and people interested in Mercari Group’s technologies.
Participation fee: Free
Venue：TODA HALL & CONFERENCE TOKYO
How to Participate: Please register on this page.
【Official Site】
For any additional information about this event, we will announce it on @MercariGears as it becomes available. If you’re interested, please follow us.
