Backend Engineer, Product Data - Mercari

Job Description

• 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.

Responsibilities

• Design and evolve product catalog schemas and ID/mapping strategies with clear contracts for downstream teams.
• Build, operate, and improve ingestion + enrichment pipelines (SQL + service code) that normalize partner data and join products with category/brand/maker/attribute signals.
• Maintain category taxonomy and mapping datasets/configuration, including safe fallbacks for unmapped cases.
• Define attribute requirements and quality rules per category to support product discovery surfaces (facets, filters, browsing).
• Establish data quality guardrails (validation, coverage, freshness monitoring) and close operational gaps (release/tag workflows, runbooks, predictable partner support).
• Improve internal tooling for operators/admins and maintain multilingual readiness (i18n) for catalog/attribute labels when needed.
  

Unique Challenges

• Balancing evolving partner schemas and changing product requirements while keeping stable, well-documented contracts for multiple downstream consumers.
• Operating high-impact catalog systems with strong reliability expectations (correctness, freshness, rollback safety) and meaningful quality KPIs across large, heterogeneous datasets.

Qualifications

Required Experience/Skills

• Strong catalog/metadata domain modeling (product, SKU, category, brand/maker, attributes) and identifier mapping.
• Strong SQL and experience building data transformations/enrichment logic.
• Experience operating data pipelines or data-heavy services with validation, monitoring, and incident readiness.
• Ability to write clear documentation and drive cross-team alignment on contracts and rollout plans.
• Proficiency in backend/service development and ownership mindset (design, implementation, on-call/operations).

Preferred Experience/Skills

• Experience integrating and operating long-lived external partner data integrations.
• Multilingual data modeling / i18n workflows for catalogs and attributes.
• Experience with event-driven pipeline patterns (pub/sub fanout, retries, DLQs).

Language

• Japanese: Nice to have (not required)
• English: Business level or above

For details about CEFR, see here.

About the Company

Our Mission

Mercari is a Japan-based company with the mission of “creating value in a global marketplace where anyone can buy & sell.” Having continuously worked toward this goal since our founding in 2013, we are now transforming from a startup into a global player. While this transformation brings its own specific set of challenges, we believe that solving them one after another will allow us to fully achieve our mission. Are you interested in working together to take on these exciting challenges?

Our Culture

Mercari’s culture has been central to the company since our founding, with the three core values of Go Bold, All for One, and Be a Pro. In addition, the “Trust & Openness” value was introduced to embody our culture of mutual trust, where information remains transparent and rules are kept to a minimum. Regardless of how big Mercari gets, our culture is essential to achieving our mission and will be promoted throughout our organization.

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.