Software Engineer (Site Reliability) - Mercari

JD in Japanese follows. 英文の後に和文JDをご覧いただけます。

Software Engineer (Site reliability) - Mercari

• Employment Status: Full-time
• Work Hours: Full Flextime (no core time)
• Office: Roppongi

For more details, see the Overview of Our Positions section on our Careers site.

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

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

In the SRE Team drives the reliability, scalability, and operational excellence of Mercari Group’s production services, including Mercari, Merpay, and Mercoin. We make customer experience observable through CUJ SLOs and turn those insights into meaningful service improvements. Working across Google Cloud and Kubernetes, we strengthen incident response, reduce toil, and build resilient systems. As AI accelerates development, we are advancing guardrails, autonomous operations, and cross-team collaboration to prevent incidents, recover faster, and improve products end to end.

See here for more information about our mission and values.

Work Responsibilities

• Operate hundreds of production microservices on Google Cloud (Kubernetes, managed services) under SLO targets, including on-support rotation for urgent issues.
• Lead end-to-end reliability epics independently — from design through rollout, monitoring, and post-launch iteration.
• Define and operate SLOs and SLIs for critical user journeys, using error budgets to prioritize work with product teams.
• Lead incident response, advance the team's postmortem culture, and drive follow-ups that prevent recurrence.
• Build autonomous AI agents for detection, triage, and recovery (log analysis, alert summarization, RCA, remediation) with clear safety.
• Write Infrastructure as Code with Terraform and build automation to reduce toil and scale operations across a large microservices environment.
• Build and maintain monitoring, alerting, and tracing on Datadog tied to user impact, with short detection-to-mitigation time.
• Perform reliability and performance tuning on production workloads (capacity planning, autoscaling, load shedding, dependency hardening).
• Partner with product and platform teams on production readiness reviews, capacity planning, and new infrastructure adoption.
• Strengthen reliability governance through engineering (risk assessment, audit response, compliance-as-code).

Unique Challenges

• Driving reliability across a wide business portfolio (Marketplace and Fintech) at Mercari scale, through a CUJ SLO that grounds product decisions and operational policy in user impact.
• Working at the frontline of AI-driven development velocity and the operational strengthening it demands — you will help shape the SRE culture that emerges as engineers and autonomous agents share the work.
• Partnering with engineering teams that own reliability and resilience and act on data, so reliability improvements compound across the company.
• Balancing ~50% reactive work (alerts, on-support tickets, operations, incident response) with project delivery.
• Working in a bilingual environment: you use both Japanese and English every day, within the team and across teams.

Qualifications

• Required Experience/Skills
• Production SRE experience with service ownership, availability targets, toil reduction, and operational readiness, including using SLOs and SLIs to prioritize reliability work alongside development teams.
• Experience operating production services at scale (>10K QPS, or owning multiple production microservices) under SLOs.
• Production experience with Google Cloud (compute, networking, managed services) and Kubernetes-based workloads.
• Infrastructure-as-Code experience (Terraform) and scripting in Go, Python, or shell.
• Hands-on experience with monitoring and observability (Datadog or equivalent), including alert design and reducing alert fatigue.
• Experience owning incident response, postmortems, and on-call or on-support rotations.
• Ability to lead epics end-to-end without teammate support.
• Willingness to learn and apply AI to operational workflows beyond your core SRE expertise.
• Preferred Experience/Skills
• Experience designing or running platform-wide SLO programs across multiple services or business units.
• Experience applying AI to operational workflows (log analysis, alert summarization, runbook assistance, RCA, remediation) with evaluation of accuracy and safety.
• Experience operating high-scale Kubernetes platforms, or distributed systems internals (scheduling, consistency, failure recovery).
• Experience leading reliability or platform initiatives that span multiple teams.
• Experience strengthening reliability governance through engineering (compliance-as-code, automated audit evidence, risk assessment).
• Language
• Japanese: Independent (CEFR – B2)
• OR English: Independent (CEFR – B2)

For details about CEFR, see here .

Learn More About Mercari Group

• Careers site: https://careers.mercari.com/en/
• Mercan: https://mercan.mercari.com/en/
• Social media: X / Linkedin
• SREcon26 Americas - It's Not Always the Network (But Here's How to Prove It): Kubernetes Packet Capture for SREs
• アーキテクチャConference 2025 - SRE視点で振り返るメルカリのアーキテクチャ変遷と普遍的な考え

Recruiting at Mercari

At Mercari Group, we value empathizing with and embodying the mission and values ​​of the Group and each company. To promote the creation of an organization that maximizes the total amount of value exhibited by all members, we would like to understand the experience and skills of each candidate as accurately as possible.

Recruiting cycle at Mercari Group

• Application screening
• Skill assessment: For engineering positions, you will be asked to complete a skill assessment on HackerRank or GitHub. For non-engineering positions, you may be asked to complete an assessment depending on the position. (The timing of the assessment may coincide with the interview process.)
• Interview: The number of interviews may vary depending on the position.
• Reference check: We will ask for online references around the timing of the final interview.
• Offer: Offers will be determined carefully in consideration of the final interview and the reference check.

Learn more about our recruiting process here .

Equal Opportunity Hiring

Here at Mercari, we work to realize a world in which no one’s potential is limited by their background and everyone has the opportunity to freely create value. We also firmly believe that a mindset of Inclusion & Diversity is essential for us to achieve our mission.

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