Software Engineer, Android (Tokyo)

Tokyo, Japan · Engineering · EN/JP



(Japanese follows English)

▼Our Mission

Mercari is in the process of strengthening our engineering organization as part of our efforts to become a world-class tech company.

In order to achieve our goal of creating an outstanding team of 1,000 engineers over the next 3 years, we are placing a heavy emphasis on hiring and training new members while also creating an environment that allows engineers to work to the best of their ability. To make this possible, we need highly skilled engineering managers to work with us.

With a strong team of engineering managers and engineers, we aim to become a tech company that can solve society’s problems using technology and work towards Mercari’s mission of creating value in a global marketplace where anyone can buy & sell.

▼Our Values (Go Bold, All for One, Be Professional)

The path to creating a leading global marketplace is not without challenges. In order to create new and innovative solutions, all members must take advantage of their unique skill sets and have a sense of responsibility and ownership for their work. We are looking for new members to join us in achieving this goal under our values: Go Bold, All for One, and Be Professional.

▼Job Description

As a member of the Mobile team, you will work as an Android professional to promote Mercari’s business and maximize project output.

Mercari has been downloaded about 75 million times in Japan and has about 10.75 million monthly users. Mercari’s mobile team is currently working on a major re-architecture of the Android/iOS apps in order to create a structure where they can conduct further large-scale development while maintaining speed and security. The team is also working on various other projects, such as developing new features and improving the UX.

The mobile team consists of members from many different countries; we hope to unlock the potential of this diverse team in order to make even greater achievements.


・Improving Mercari’s UI/UX

・Improving quality with a focus on stability and performance

・Continuous improvement of the codebase, including the major re-architecture

・Handling updates for the Android app

・Developing new services and linking them with other services



「3年で1,000人規模の優秀なエンジニアリング組織」を作るために、エンジニアを採用・育成して仲間を増やすことと、エンジニアリングに集中できる環境を作ることを同時にGo Boldに行う必要があります。テクノロジーで人々の課題を解決ことができるテックカンパニーとなり、メルカリのミッションである「新たな価値を生みだす世界的なマーケットプレイスを創る」ことが我々の目指す未来です。

▼3つのバリュー(Go Bold, All for One, Be Professional)

世界的なマーケットプレイスを創るために我々は集まっていますが、この目標への道のりは決して平坦ではありません。まだ誰も挑戦したことのないようなイノベーションや破壊的な創造を起こすため、我々は各自がオーナーシップを持ち、専門的能力を発揮することで、メルカリというチームとして最高のプロダクトを創ります。このことを達成するために我々は「Go Bold - 大胆にやろう」「All for One - 全ては成功のために」「Be Professional - プロフェッショナルであれ」という3つのバリューのもと行動しています。


メルカリの事業を推進していくために、Mobile チームの一員、とくにAndroidのプロフェッショナルとして、プロジェクトの成果を最大化することにコミットしていただきます。










(Japanese follows English)

▼Minimum Requirements

・Experience developing native Android apps

・Extensive knowledge in object-oriented software development, solid MVVM/MVP architecture, multithreading, networking and memory management.

・Experience with continuous improvement of codebases and large-scale team development

・Knowledge of standard Android libraries and frameworks

・Ability to develop features while conducting unit tests using JUnit and Mockito

・Software development experience with Kotlin at work

▼ Preferred

・Ability to gather the team’s consensus and make decisions when selecting technology for large-scale development

・Experience communicating with the business side to decide technical approaches to implement ideas

・Experience background in any of the following is a plus: Product Design, UI/UX design, Backend/Fullstack engineering.

・Experience managing a team of 3 or more members

・Experience developing and operating native apps with large user bases

・Experience independently planning, developing, and operating apps

・Knowledge of performance optimization

・Experience training junior members

・Ability to communicate with development teams in English (written and verbal communication skills)

▼ Our Ideal Candidate

・Capable of taking on bold challenges and learning from mistakes

・Capable of working independently and taking initiative to lead the team to success

・Possesses a strong sense of responsibility and works hard to achieve their goals

・Capable of communicating proactively and producing output in a highly global team

▼Languages and technologies we use

・Software development: Java and Kotlin
・Network transport: Protocol buffers
・Build Environment: Gradle + OkBuck
・Day to day development: LeakCanary, Dagger, and okhttp
・UI Testing: Espresso

Interview Process

・Resume Screening

・Take-home skill test on Github (deadline: one week)

・2 Technical Interviews on the same day (about Computer Science & Domain knowledge)

・Interviews with Android or Mobile engineers/ Manager/ VPoE ( 2-3 rounds depending on scheduling)


*The process is subjected to changes and skill test may be skipped if there is enough information for proof.



・オブジェクト指向ソフトウェア開発、MVVM / MVPアーキテクチャ、マルチスレッド、ネットワーク、メモリ管理に関する豊富な知識



・JUnit, Mokito を使った単体テストを行いながら機能開発に従事する能力

・Kotlin での実務経験




・プロダクトデザイン、UI / UX設計、バックエンド/フルスタックエンジニアリングのいずれかの経験






・開発者間での英語でのコミュニケーション能力 (読み書きと会話能力)




・構築環境:Gradle 、OkBuck









▼Contract Type


 Probationary Period: 3 months (salary same as above)



▼Work Hours

・Fixed working hours 10:00-19:00

 Flex time (core hours 12:00-16:00, 60 minute lunch)


・Annual salary, paid monthly

・Based on your experience, skills and potential

・Reviewed twice a year


・5-day work week (Sat/Sun off)

・National holidays, paid time off, summer/New Year's vacation, congratulatory leave, compassionate leave








 フレックスタイム制度あり(コアタイム:12:00~16:00 [休憩60分] )









(Japanese follows English)

・Health insurance

・Incentive program

・Employee stock ownership plan

・Full transportation coverage

・Custom PC

・Dual screen if needed

・Company smartphone

・Visa support

・New Employee Benefits at Mercari「mercibox












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Mercari Engineering Blog


If you are looking for job opportunities in the United States, please apply from Mercari US careers page

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