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 “MECHANISM Stage”!
If you haven’t registered yet, take a look and you will find sessions that will interest you. Please register here.
13:00 – 13:20 Leveraging LLMs in Mercari Hallo
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Mercari Hallo is Mercari’s new business in the field of on-demand work. Since the service launched in March 2024, it has continued to grow and has recently surpassed 12 million registered users.
Mercari Hallo’s ML Team was established in October 2024, around six months after the service launch. Since then, the team has been working on many product improvements using AI/ML.
In this session, we will introduce some Mercari Hallo features that use LLMs, along with the LLMOps platform that supports them. Specifically, we will discuss the Easy Job Listing feature, which automatically creates job listings using LLM technology, and our use of LLMs in analyzing job listings with risk prediction before they are published. Mercari Hallo has already released many features leveraging LLMs, and uses more than 50 types of prompts for different purposes in production. This means that the LLMOps platform for managing prompt quality is very important.
Through this session, I hope to share some key points for product implementation of LLMs, practical tips for LLMOps such as prompt management and automated evaluation frameworks, and other knowledge we gained in the process of implementing LLMs in Mercari Hallo.
13:30 – 13:50 Mercari’s CDN Migration from Fastly to Cloudflare
At Mercari, we began a gradual transition from Fastly to Cloudflare as our CDN provider in 2023, and as of 2025, the transition has been fully completed.
In this session, we will share the approach we took to ensure a safe and smooth transition, as well as the lessons we learned along the way.
Since we will mainly discuss the migration process rather than compare specific CDN providers, we believe that even those who are not considering changing their CDN provider will be able to take away valuable insights on migration strategies and processes.
14:15 – 14:35 The Invisible Backbone: AI-Native Observability for Modern Platforms
Imagine observability that configures itself, adapts seamlessly to change, and cuts through the noise of alert fatigue. In this session, we’ll share how Mercari built an AI-Native platform that delivers zero-config monitoring, consistent visibility, and intelligent alerting out of the box.
Join us to see how autonomous observability is shaping the future of reliable, developer-friendly cloud platforms.
14:35 – 15:05 Running 1000 End-To-End Web Tests Daily
We run a LOT of end-to-end web tests at Mercari US, and making sure the tests are quick and useful is a challenge. In this talk, I describe our approach to running the tests on each pull request, adding new tests, and running tests targeted at each feature area. If you want to see how running thousands of end-to-end tests daily works, this talk is for you.
15:15 – 15:35 Mercari’s Internationalization Journey
Over the past two years, Mercari has enabled international customers to purchase on its marketplace.
This presentation focuses on the journey to internationalize the product, with a particular emphasis on user-generated content translation, including how LLMs helped reduce the cost by 100x.
16:00 – 16:20 EGP – Mercari’s CRM Platform: Built Once, Powering Many
EGP began as a simple hard-coded CRM and has since evolved into a scalable, UI-driven platform for marketers. As the system grew, complexity created usability and operational challenges, especially at larger business scale. We’ll share how we tackled these issues through system design and AI-powered UI enhancements, and what we’ve learned along the way.
16:30 – 16:50 Securing the Future of Workflow Automation and AI Agents
As enterprises embrace workflow automation and AI agents, new risks emerge: orphaned systems, over-privileged agents, and tangled permission models. This talk explores how to resolve these challenges to safely unlock the full potential of automation and AI in your organization. Learn practical approaches to enable secure, scalable adoption while empowering users to innovate with confidence.
17:00 – 17:20 A New Era of Data Utilization Driven by AI/LLMs: Creating an Analytics Platform for Humans and Data Analysis AI Agents to Collaborate
We have built an AI agent named Socrates that enables employees to perform data analysis through interactions using natural language. The introduction of Socrates has brought about a transformation allowing anyone to easily generate and execute SQL queries and visualize and interpret the results, thereby significantly lowering the barriers to data utilization. In this session, we will discuss the background of Socrates’ creation, the technology that supports it, and how we envision the future of the data utilization experience brought about by collaboration with AI.
Apply for “mercari GEARS 2025” here.
For details on other sessions, please see below.
PASSION Stage session details are here.
GROW 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.
