In 2014, Mercari launched “Mercari US,” the company’s C2C marketplace business in the United States market.

In fiscal 2025, Mercari US achieved its first ever full-year profit. Then, in the second quarter of fiscal 2026, cumulative gross merchandise value (GMV) increased by 10% year-over-year. In the company’s most recent third-quarter financial results, the figure reached +18% year-over-year. With a lean organization, Mercari US continues to steadily accelerate its growth.

Behind the scenes of the organization’s success are a series of changes implemented over the past two years. These have involved reviewing the US business’s structure and strategy, listening closely to user feedback, and applying layer after layer of meticulous improvements.

For this article, we spoke with two Mercari US executives who have been leading these changes, Jeff LeBeau (@jeff), Vice President of Growth*, and Takuma Yamaguchi (@kumon), Vice President of Engineering. In this interview, they candidly discuss the turning point of the business, the philosophy of the organization, and what they’d like to see from future team members.

*as of publication

Our best members are assembled here—The current state of our V-shaped recovery line

—To kick things off, could you give us a rundown of the current situation of the US market and tell us where Mercari US now finds itself within that market?

@jeff: To be frank, Mercari US’s current members are the best we’ve ever gathered, and we are in an environment where they are able to create a product that can grow significantly.

In the American market, particularly among the younger generation, the mindset that buying used is cool is spreading, and the mindset around mass consumption is also changing. This is becoming a tailwind for Mercari. That said, we are still in the midst of a V-shaped recovery, and I believe that the coming phase is very important.

@kumon: That feeling spills over into the vibe inside the company. We’re now in the midst of a positive cycle, but we walked a less than straight path to get here. Up until a few years ago, there were times when the projects the company prioritized didn’t go so well, and the organization was pulled into a negative spiral.

However, in the last two years, this has reversed completely. Now there’s a sense that even things that don’t go well can be leveraged in the next initiative. The ease with which people communicate with each other and the sense they have that they can speak openly also give the impression that things are going well.

As a lean organization, each individual’s actions are linked directly to the product and the business. I believe that the experience of overcoming that phase together with the current members creates a natural sense of unity within the team.

Building a unique position in a highly competitive US market

—What can you tell us about Mercari US’s position in the US market?

@jeff: The US market is extremely competitive. Specialized marketplaces emerge one after another, and brands and manufacturers have also started launching their own marketplaces.

On the other hand, there are almost no comprehensive C2C marketplaces like Mercari US with a GMV of 100 billion yen. It’s a fact that we have established a certain advantageous position in the sense that there are limited players with our scale.

—How does having offices in both the US and Japan impact product development?

@kumon: Having a location in the US is a tremendous advantage. Unless you’re immersed in an environment where you can actually experience the service, it’s not easy to suggest improvements. You can’t really see what the competition is doing and compare yourself against them unless you try using their services yourself. Only those who are actually on the ground here can truly experience other companies’ services firsthand as users.

That said, it’s not simply a matter of having everyone on-site; being able to collaborate easily with Mercari Japan (JP) is also a major advantage. I believe that being based in both locations is a huge benefit.

Definite changes in the organization’s outlook

—What has been behind such significant changes over the past two years?

@jeff: It’s not so much about one big move, but rather the result of steady efforts over time.

We redefined the value Mercari US should deliver based on our data analysis and user interviews, and we have been implementing initiatives one after another. I have been with Mercari Group for ten years now, and I feel that our initiatives have never been more successful.

@kumon: During the COVID-19 pandemic, our business grew significantly, so we greatly increased our headcount. However, as demand fueled by people locked down in their homes subsided, GMV declined, and we were forced to conduct layoffs. After that, there was a major change in leadership, which shifted our focus to improving the core product. As a result of making steady improvements, we achieved profitability and re-growth.

I believe that getting to a stage where we were able to reflect on the basics once again and continue making improvements from the user’s perspective was a significant turning point.

—Were there changes to how engineering operated as well?

@kumon: The development methods themselves have not changed much, actually. We’re still a lean organization with clear focus areas—that much remains the same. However, the landscape within the organization has definitely changed.

Previously, the priorities of members assigned to large projects were quite clear, while the priorities of those not involved in those projects were sometimes less clear. With decision-making becoming more transparent across the organization, everyone finds it easier to make judgments in alignment with each other, regardless of whether they work within or outside of a particular focus area.

@jeff: An example of this is how we’ve continued to set the same growth-related objectives throughout the year with OKRs (objectives and key results). Since the entire organization continues to work toward the same goal on a yearly basis, the criteria for decision-making remain stable even across its different layers. Structural aspects like these help support our organization.

Integrating product and engineering into the growth organization

—Can you tell us about the unique structure of your organization?

@kumon: Currently, Mercari US has engineers and product teams within the growth organization. I also directly discuss the roadmap with engineering directors, managers, and product leaders to ensure alignment. I always make a conscious effort to avoid confusion in priorities.

—Why is that?

@jeff: I wanted to prioritize value delivery to users and the business growth that arises from it, so I included both product and engineering in the growth organization, eliminating silos in the process. Since the changes we made had an impact on the numbers, we had the idea of further accelerating this effect going forward, which led to our current organizational structure.

—Does your decision-making process do anything differently?

@kumon: Our organizational structure features parallel teams called pods, which are small, cross-functional units equipped with all the capabilities they need to succeed.

Essentially, no two people in each pod have the same role. Where engineers are concerned, there is one backend engineer; for the frontend, there is one web engineer and one mobile engineer, so each member must make decisions within their respective role in order for things to move forward. Rather than saying that we allow people to use their discretion, I think it’s more accurate to say that the pod environment is one where nothing moves forward unless everyone does their part. However, that does not mean that each person is isolated; where necessary, they can receive support from other members or managers who possess the same expertise.

Additionally, to advance projects amid limited engineering resources, backend engineers contribute to frontend implementations, and vice versa. AI initiatives aside, we have always operated this way.

@jeff: Working this way is also a part of All for One, one of Mercari’s values. Our organization is lean with almost no hierarchy, allowing for people to openly exchange opinions. This leads to speed, which is ultimately reflected in the numbers.

AI-Native as a tailwind for our culture

—How is AI-Native being advanced within Mercari US?

@jeff: Over the past year and a half, Mercari US has been operating under the principles of avoiding unnecessary actions, maximizing resources, and making a significant impact with a small team. I think our strength lies in advancing the use of AI based on that foundation. In other words, the expanded capabilities that AI provides to individual members have served as a tailwind for our established approach.

—Are there any difficulties involved in promoting AI?

@kumon: While AI can improve the efficiency of our existing workstyles, that alone isn’t enough to unlock its full potential. To really leverage the technology effectively, it’s necessary to change the development process and the decision-making system itself.

I believe there is potential to accelerate further with AI precisely because there is still room for change.

A highly hands-on approach as we move into the next phase

—What are some of the aspects you prioritize for hiring?

@kumon: A common factor across all domains is the applicant’s level of interest in the product. No matter how high a potential hire’s engineering skills are, if they aren’t interested in the actual C2C business, it makes it hard for us to invite them in. Whether someone will be inclined to suggest improvements to the product or to propose new marketing initiatives is a crucial point.

Another important factor we consider is a person’s ability to grasp a feature comprehensively from end to end. Given the broad scope of discretion our members have, we want to hire people with a willing mindset to make contributions that slightly exceed their own area of responsibility while overlapping with adjacent areas. Both Jeff and I are in charge of the final interviews, and we always make sure to discuss the product there.

@jeff: I am very conscious about a person’s cultural fit. Since our organization is small, adding one person is a significant development. We carefully evaluate whether a candidate is likely to embody Mercari’s values (Go Bold, All for One, Be a Pro, Move Fast) and genuinely resonate with our mission; we do this for the company, but also for the benefit of the candidate as well.

Applicants come from a diverse range of backgrounds, from big tech companies to startups, and some have run their own businesses. Rather than focusing on the job titles they’ve held over the course of their work history, we place greater emphasis on whether someone has a strong hands-on approach.

—The members of Mercari US working in the US and those involved in the US business while living in Japan have diverse backgrounds and speak different languages. Amid such communication barriers, how do you carry out your work with speed?

@jeff: Mercari US is composed of members from diverse backgrounds, and Mercari JP is also becoming a diverse organization.

I often get asked if there are any communication issues that make collaboration among our diverse members difficult, but in my experience, most of the difficulties come from time zone differences. There are almost no cases where culture or language acts as a barrier.

@kumon: I feel the same way when collaborating with JP. About five years ago, in addition to time zone differences, the language barrier was significant, but now more than half of the engineers at JP are non-Japanese citizens, so technical communication often occurs in English, and consequently the language barrier has almost disappeared. That’s why I believe we can further increase the speed of collaboration with JP from here.

—What challenges do you see Mercari US facing going forward?

@jeff: Reproducible growth is a huge topic. The main pillars for achieving this are product development and accelerating our AI-Native transformation; continuing to deepen these areas is essential. Even as the business grows in scale, we aim to maintain a structure that will allow each individual to have a significant impact. To prevent barriers from forming between organizations, we will continue to visualize the impact that each individual has. That is something we want to have in mind throughout this year.

@kumon: Regarding engineering, we need to change the development process and system operations not just to streamline existing methods by using AI, but to redesign the development process and system operations around collaboration with AI agents. Since we are making significant changes to established processes, there’s a risk of triggering confusion and temporary drops in productivity, but I believe these changes are necessary to aim for true AI-Native software engineering.

—So, to wrap things up, what would you like to say to people interested in a career at Mercari US?

@jeff: Mercari US is entering a new growth phase. I want to work with people who are genuinely committed to engaging with our C2C service in the United States with an All for One mindset.

@kumon: I feel much the same way. I want to work with people who are motivated not just by personal growth, but by the desire to help grow our services through trial and error in the US C2C market.

When it comes to engineers, we look for individuals who not only focus on growth and developing new features, but also pay attention to improving the platform and infrastructure, take initiative beyond their defined responsibilities to propose improvements, and follow through on those proposals. I believe this is definitely an environment where people like that will thrive.