Senior Software engineer, Android (Mobile Enablement)

必須

• Bachelor's degree in Computer Science, Engineering, or equivalent practical experience.
• Strong proficiency in Kotlin and Android development frameworks (Jetpack libraries, Jetpack Compose, Android SDK).
• Solid understanding of mobile architecture patterns (MVC, MVVM, MVI, Clean Architecture, etc.).
• Demonstrated experience with large-scale mobile applications and complex codebases.
• Experience integrating with backend APIs and asynchronous/concurrent programming.
• Strong analytical and problem-solving skills; ability to navigate ambiguity.
• Excellent communication skills and ability to explain technical concepts clearly.
• Passion for building user-facing mobile products.
• English: Independent (CEFR - B2) Required

歓迎

• Experience with large-scale mobile apps serving millions of users.
• Expertise in performance optimization, instrumentation, and mobile observability (e.g., crash analysis, metrics).
• Experience with modern Android platform capabilities (e.g., Kotlin Multiplatform, Baseline Profiles, app performance tooling).
• Contributions to open-source Android projects or active involvement in the mobile community.
• Experience driving technical initiatives across multiple teams or owning platform-level components.
• Familiarity with CI/CD for mobile, automated testing frameworks, build systems (Gradle), and release management.
• UI/UX sensitivity and an eye for detail in crafting polished user experiences.
• Japanese: Independent (CEFR - B2) Optional

使用ツール

Organization/Team Mission

• The Mobile Enablement team transforms mobile development into a seamless, automated, and cross-platform ecosystem. Our mission is to deliver innovative features and user experiences to maximize product-facing impact for Mercari's business. We simplify engineering workflows, reduce repetitive tasks through automation/AI, and enable broader collaboration across teams.
• By streamlining coding, testing, releases, and operations, we accelerate innovation and scalability, ensuring mobile development keeps pace with Mercari's global growth and business needs. Join us to redefine how we build and deliver the Mercari experience!
• As a Mobile Enabler mainly focusing on the Android ecosystem, you will own and evolve the entire Android engineering ecosystem at Mercari, from lower-level platform capabilities to higher-level architectural decision-making, providing the best experience for our engineers and Mercari users.

Tech Stack

• Android Development: Kotlin, Jetpack Compose, Kotlin Coroutines & Flow
• Build & Tooling: Gradle (Develocity), Android Studio
• API & Data: Protocol Buffers
• AI Tools: Claude Code, Codex, Cursor
• CI/CD: GitHub Actions, GKE

Work Responsibilities

• Specific work responsibilities are listed below:
• Periodically join your fellow product engineers in designing, implementing, and maintain high-quality Android features to understand their reality and define the best solutions for them.
• Own end-to-end development for platform and architectural solutions, from requirements definition through architecture, implementation, testing, and release.
• Lead architectural design for complex features and system components, ensuring maintainability, scalability, and reliability.
• Optimize app performance, startup time, memory usage, and stability across diverse devices and OS versions.
• Work closely with machine learning, backend, infrastructure, product, and design teams to deliver seamless mobile experiences, as well as other feature-owner Android engineering teams.
• Take ownership and evolve Mercari's mobile platform, SDKs, and shared modules used across teams.
• Drive high code quality through code reviews, automated testing, CI/CD improvements, and rigorous documentation.
• Champion engineering best practices and contribute to guidelines and standards across Client Engineering.
• Stay current with the latest developments in Android, Kotlin, Android Views, Jetpack Compose, coroutines, and mobile architecture patterns.
• Bring innovative ideas to improve user experience, developer experience, and operational efficiency.
• Take ownership of initiatives that span multiple teams, driving alignment and technical decision-making.
• Mentor junior and mid-level engineers, helping strengthen the overall technical capabilities of the team and the engineering organization.

Unique Challenges

• Enabling dozens of mobile engineers in delivering awesome experiences to our 20M+ users by leveraging a diverse skillset to provide the best mobile ecosystem.
• Deliver highly performant and reliable functionality in a fast-paced environment with complex product requirements.
• Bridge consumer-grade UX expectations with robust engineering architecture and infrastructure.
• Influence platform-wide technical strategy, shaping the future direction of Mercari's mobile and AI-native cross-platform ecosystem.
• Lead cross-functional efforts in ambiguous problem spaces where user needs and technical constraints must be balanced.