Software Engineer, Platform Engineering (Observability)

About Us

Mercari is a Japan-based C2C marketplace company founded in 2013 with the mission to "Create value in a global marketplace where anyone can buy & sell." From being the first tech unicorn from Japan before its IPO in 2018, we have come a long way towards becoming a global player and continuously and diligently work towards our transformation journey with a strong focus on our mission.

Since its inception, Mercari Group has worked to grow its services, investing in both our people and technology. Over time Mercari has expanded from being the top player in the C2C marketplace in Japan to new geographies like the U.S. We have also successfully launched new businesses such as Merpay, a mobile payment service platform with a vision to create a society where anyone can realize their dreams through a new ecosystem centered not only on payment service but also on credit. Today, Mercari Group is made up of multiple subsidiary businesses including logistics, B2C platform, blockchain, and sports team management.

For our services to be utilized by people worldwide, there is still a mountain of work ahead of us. This endeavor naturally requires the capability of the best talent and minds, and that is exactly the reason for us to launch the India Center of Excellence. With your help, we will continue to take on the world stage and strive to grow into a successful global tech company.

Our Culture

To achieve our mission at Mercari, our organization and each of our employees share the same values and perspectives. Our individual guidelines for action are defined by our four values: Go Bold, All for One, Be a Pro and Move Fast. Our organization is also shaped by our four foundations: Sustainability, Diversity & Inclusion, Trust & Openness, and Well-being for Performance. Regardless of how big Mercari gets, the culture will remain essential to achieving our mission and something we want to preserve throughout our organization. We invite you to read the Mercari Culture Doc which summarizes the behaviors and mindset shared by Mercari and its employees. We continue to build an environment where all of our members of diverse backgrounds are accepted and recognized, and where they can thrive while holding dear to Mercari’s culture.

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

Why Observability Matters - Now More Than Ever

Observability sits at the center of making applications reliable. As engineering organizations accelerate with AI-generated code and rapidly evolving architectures, the ability to understand what's happening inside your systems becomes the difference between catching a problem before it reaches users and learning about it from them. Our team exists because every line of code - whether written by a human or generated by AI - needs to be understood, monitored, and trusted in production.

Observability Platform Team

Our Mission: To empower Mercari engineering teams with the visibility and insights they need to build resilient, high-performing systems that deliver exceptional user experiences.

What we do:

We are the team that makes sure nothing breaks silently. We build the observability platform that turns the complexity of 500+ microservices into clarity - giving every engineer at Mercari the real-time signals, intelligent alerts, and deep diagnostic capabilities they need to ship fast and sleep well. From the moment code hits production to the instant an anomaly emerges, our platform is the nervous system that keeps Mercari's services healthy and our engineers confident.

Recent or ongoing projects

• Building AI-powered solutions for automated incident detection and response to reduce Mean Time to Detect (MTTD) and Mean Time to Mitigate (MTTM).
• Evolving our monitoring and alerting platform to reduce noise, improve signal quality, and enable self-service for product engineering teams.
• Designing and implementing observability standards and best practices across 500+ microservices.
• Improving developer experience by building self-service tooling for instrumentation, dashboards, and alerting.

Work Responsibilities

We're looking for a Senior Platform Engineer with deep expertise in observability systems at scale. This role is part of our Platform Engineering division, which builds and operates the foundational infrastructure powering all of Mercari's services. You will drive the technical direction of the observability platform, identify areas for improvement, and build solutions that measurably reduce incident detection and mitigation times. You'll lead by example, mentor others, and help build a strong engineering culture within the team.

The ideal candidate is passionate about giving engineers the visibility they need to ship with confidence. You're someone who sees noisy alerts and blind spots as problems worth solving, and who gets energy from making complex systems understandable.

You'll take ownership of our observability stack end-to-end - from data collection and pipeline efficiency to intelligent alerting and AI-assisted incident response. We value engineers who lead by example, mentor others, and build a strong engineering culture within the team.

What you will do

• Design, build, and operate Mercari's observability platform - covering metrics, logs, traces, and alerting at scale.
• Drive measurable improvements in Mean Time to Detect (MTTD) and Mean Time to Mitigate (MTTM) across all services.
• Build AI-powered solutions for automated anomaly detection, alert correlation, and incident response assistance.
• Develop self-service observability tooling that enables product engineers to instrument, monitor, and alert on their services independently.
• Define and champion observability standards, best practices, and SLO frameworks across the engineering organization.
• Collaborate with other platform teams, SRE, Security, and product engineering teams to ensure comprehensive system visibility and reliability.
• Automate operational workflows to reduce toil and improve the team's efficiency.
• Lead technical decisions, mentor team members, and actively shape the engineering culture within the observability team.