Rakuten

Senior Software Developer, Front-end (React and

React Native) - BSS Department (BSDD)

Job Description:

Job Description:

Department Overview

The responsibility of BSS Development Department (BSDD) is system development of B2C BSS

systems and making sure of requirements from executive and business team.

Position Overview:

We are seeking a skilled React Developer with expertise in React Native to join our dynamic

team. The ideal candidate should have a solid background in building scalable applications and

a passion for crafting high-quality software solutions. This role offers an opportunity to work on

challenging projects and collaborate with talented teams to deliver exceptional user

experiences.

Responsibilities:

• Develop new user-facing features using React.js and React Native.

• Build reusable components and front-end libraries for future use.

• Translate designs and wireframes into high-quality code.

• Optimize components for maximum performance across a vast array of web-capable

devices and browsers.

• Collaborate with cross-functional teams to define, design, and ship new features.

• Work closely with Product Managers and UI/UX Designers to implement versatile front-

end solutions.

• Advocate for best practices in front-end development and mentor junior developers.

Mandatory Qualifications:

• 8-10 years of professional experience in front-end development.

• Strong proficiency in JavaScript and TypeScript.

• Extensive experience with React.js and its core principles.

• Prior experience with React Native for mobile application development.

• Familiarity with RESTful APIs and modern authorization mechanisms.

• Experience with state management libraries such as Redux or MobX.

• Knowledge of modern authorization mechanisms, such as JSON Web Token.

• Familiarity with code versioning tools such as Git.

• Excellent problem-solving skills and ability to troubleshoot complex issues.

• Bachelor's degree in Computer Science or a related field (or equivalent work

experience).

Desired Qualifications:

• Experience with GraphQL.

• Japanese Language Proficiency :- Business level is Good to have

• Familiarity with server-side languages such as Node.js.

• Understanding of Agile methodologies.

• Contributions to open-source projects or active GitHub profile.

#engineer #developmentsupport #technologyplatformdiv

Languages:

English (Overall - 3 - Advanced)

RAKUTEN

Senior QA Engineer - eCare Product & QA Group, BSS

Development Department (BSDD)

Job Description:

Department Overview

The mission of BSS Development Department (BSDD) is to accelerate our contribution

to the telecommunications business by providing an innovative, high-quality and stable

ecosystemized B2C BSS platform. MNO business just started in 2020. 10 million subs

are coming soon. We are still expanding rapidly every year. Let's walk together to

become the No.1 telecom operator.

We are striving to deliver a simple, intuitive, and reliable platform that empowers users

to effortlessly manage their Rakuten Mobile services, stay connected, and enjoy a

superior mobile experience anytime, anywhere.

Position:

Position Details

Mobile Application Testing:

- Perform end-to-end testing of mobile applications on iOS and Android platforms.

- Conduct functional, regression, performance, usability, and compatibility testing.

- Identify, document, and track bugs and issues using bug-tracking tools.

Automation Testing:

- Design, develop, and maintain automated test scripts for mobile applications.

- Implement and execute test automation frameworks (e.g., Appium, Selenium, etc.).

- Continuously improve automation coverage and optimize test scripts for efficiency.

Test Planning and Strategy:

- Develop comprehensive test plans, test cases, and test strategies for mobile

applications.

- Collaborate with cross-functional teams (developers, product managers, designers) to

understand requirements and ensure test coverage.

- Define and implement QA best practices and processes.

Performance and Security Testing:

- Conduct performance testing to ensure the app performs well under various

conditions.

- Collaborate with security teams to identify and address vulnerabilities in mobile

applications.

Collaboration and Communication:

- Work closely with development teams to ensure timely resolution of issues.

- Provide regular updates on testing progress, quality metrics, and risks to

stakeholders.

- Participate in Agile/Scrum ceremonies and contribute to sprint planning and

retrospectives.

Mandatory Qualifications:

Technical Skills:

- Proficiency in programming languages such as Java, Python, or JavaScript for test

automation.

- Strong understanding of mobile platforms (iOS and Android) and their development

ecosystems.

- Familiarity with API testing tools like Postman or RestAssured.

- Knowledge of performance testing tools (e.g., JMeter) is a plus.

Soft Skills:

- Excellent problem-solving and analytical skills.

- Strong communication and collaboration skills to work effectively in a team

environment.

- Ability to mentor junior QA engineers and contribute to team growth.

Desired Qualifications:

- ISTQB or equivalent QA certification.

- Experience working in Agile/Scrum environments.

- Familiarity with cloud-based testing platforms (e.g., BrowserStack, Sauce Labs).

- Experience with localization testing, especially for Japanese markets.

- Japanese Language (Communicate effectively with Japanese-speaking stakeholders or

clients, if required. Translate and understand Japanese documentation or

requirements, if applicable).

#engineer #technologyplatformdiv #RakutenMobile

Languages:

English (Overall - 4 - Fluent)

Backend Engineer

About PayPay Card PayPay Card Corporation was established in 2021 to provide users a FinTech service that is more accessible and convenient compared to previous credit cards and credit services, by integrating with the PayPay payment platform, which has surpassed 66 million users since its launch (as of October 2024). We are looking for people who are passionate about refining our products at an overwhelming speed that other companies cannot match, as well as professionals who are interested in promoting the spread of cashless payments in Japan and the use of these payments as a financial life platform. Let us work together to create new value for users. ※ Please note that you cannot apply or be selected in parallel with PayPay Corporation, PayPay Card Corporation and PayPay Securities Corporation.

Job Description We are looking for backend engineers to build, or rebuild, rock solid services with a laser focus on scalability and maintainability. PayPay Card aims at revolutionizing the credit card industry, making payment easier than ever, from two different angles:

Bring the credit card experience to the next level: we have many functionalities in the pipe to improve our product, not to mention the integration into the PayPay ecosystem as PayPay Card is part of the PayPay Group.

(Re-)architect our systems landscape: we want to reassess and fix the behind-the-scenes to power a top-notch user experience. It is bundled with difficult design challenges to solve: we simply want to get it right.

As a fast-paced company leading the payments industry, we need our engineers to be versatile and enthusiastic to take on new challenges in order to stay at the forefront. Indeed, we strive for continuous improvement within our systems as well as outside our systems. Additionally, we value communication, to smoothly cooperate with other teams, and inclusivity, to efficiently navigate in a multicultural environment.

Main Responsibilities

Support the design, implementation and delivery of large scale, and complex, systems, while collaborating with product managers, frontend engineers or other team members.

Understand how to leverage infrastructure to solve large scale problems. Contribute to the team by sharing knowledge, participating in code reviews and providing

feedback to uphold and ensure best practices. Triage, debug and resolve product issues or other incoming troubles inquiries Adopt problem solving as a way of life – always go to the root cause! Support the code you write

in production.

Tech Stack

We currently work with Back-end services:

Main implementations are in Spring Boot, with a mix of Java 11/Spring Boot 2 and Java 17/Spring Boot 3.

Some legacy systems are written in Java EE. Testing is done with JUnit and Mockito Deployment relies on AWS ECS CI/CD is handled by AWS CodePipeline

Infrastructure All our services run in AWS Infrastructure is managed by AWS CloudFormation AWS CloudWatch is used for observability

Coding environment: GitHub, IntelliJ, Gradle Documentation & Project management: Confluence, Miro, JIRA Communication: Slack, Zoom, Office 365

Please note that PayPay Card is challenging its current architecture, potentially introducing new technologies and/or deprecating existing ones.

Required Qualifications

Skills in OOP language such as C# or other JVM language, such as Scala are welcome Experience with RDBMS, NoSQL databases along with distributed cache. Strong fundamentals in data structures, algorithms and object oriented programming. In-depth understanding of concurrency and distributed computing. Experience implementing platform components such as RESTful APIs, Pub/Sub Systems, and

Database Clients. Experience with microservices and event-driven architectures. Experience designing high traffic systems. Degree in Computer Engineering or Computer Science or 5+ years equivalent experience in

SaaS platform development. English business proficiency

Preferred Qualifications

Domain-driven development knowledge Java/Spring Boot experience gRPC and Kafka development experience Experience in a multicultural environment Stakeholder management is welcomed Japanese conversational proficiency is a plus

Working Conditions

Employment Status

Full Time

Office Location

Tokyo Office You can live anywhere in Japan

Work Hours

Full Flex Time (No Core Time) In principle, 9:00am ~ 5:45pm (actual working hours: 7h45m + 1h break)

Holidays

Every Sat/Sun/National holidays (In Japan)/New Year's break/Company-designated Special days

Paid leave Annual leave (up to 16 days in the first year, granted proportionally according to the month of

employment. Can be used from the date of hire)

Salary

Annual salary paid in 12 installments (monthly) Reviewed once a year Special Incentive once a year *Based on company performance and individual contribution and

evaluation Overtime allowance,Late overtime allowance,Commuting and transportation expenses, Work

style support allowance

Benefits

Social Insurance (health insurance, employee pension, employment insurance and compensation insurance)

401K

Astroscale- GNC エンジニア /Guidance Navigation and Control Engineer

Export Control Laws

Unless explicitly notified otherwise, our vacancies are covered by Export Control Laws which require

candidates to be from an "Export Safe" Country as deemed by the Japanese Government. The countries are

as follows: Japan, Germany, Australia, Argentina, Italy, USA, France, Netherlands, UK, Austria, Ireland,

Czech, Spain, Greece Canada, New Zealand, Belgium, Bulgaria, Sweden, Switzerland, Norway, Finland,

Luxembourg, Portugal, Denmark Hungary and Poland.

＜職務内容 活動/役割・責任＞ 

• 宇宙機の AOCS (姿勢・軌道制御系) /GNC (航法・誘導・制御) の開発、設計と検証を実施する。

• GNC の立場で、システムレベルの設計を支援する。：事例として、ミッション CONOPS (Concept of Operations) の

作成、FMECA (Failure Mode, Effects, and Criticality Analysis) 、及び FDIR (Failure Detection, Isolation, and

Recovery) のプロセス、設計、システム試験・検証計画等の定義。

• 制御則及びアルゴリズムの開発：RPO (rendezvous and proximity operations) およびドッキングのシナリオを設計、

解析し、シミュレーションにより検証する。

• GNC の機能性能を実現するハードウェア構成、もしくはソフトウェア構成をトレードオフし、全体のアーキテクチャを

決定する。

• 調達部門のエンジニアと協働し、調達する GNC 機器をトレードオフし、選定する。

＜必須スキル＞

• AOCS または GNC システムエンジニアとして、航空宇宙車両向け GNC ソリューションの設計、実装、テストのいずれ

かに携わった経験 3 年以上。

• または、移動体の動的制御の設計、実装、テストに携わった経験 3 年以上。ただし、大学または大学院で航空宇宙系を専

攻していること。

• アルゴリズムと制御法則の開発経験：GNC 設計とシミュレーションソフトウェア（例：MATLAB）の使用、制御法則と

実世界効果（非線形性、信号ノイズ、チューニング）の実装、アルゴリズムを運用フライトソフトウェアに変換。

• TOEIC 700 点以上の英語力。

• ビジネスレベルの日本語能力。

＜望ましいスキル＞

• AOCS または GNC システムエンジニアとして、実際の宇宙船ミッションの GNC ソリューションの設計、実装、テスト

に携わった 5 年以上の経験。

• RPO とドッキングのアルゴリズムとソリューションの実装経験があることが望ましい。

• ハードウェアのトレードオフ、ハードウェアとソフトウェアの GNC アーキテクチャ設計の経験。

• 軌道上での衛星運用経験。

• 古典的手法を超える制御則設計の経験：非線形設計、最適化。

• カメラ、IR、LiDAR を含む GNC センサーシステム（トレードオフ／調達、データ処理）の知識

＜Key activities, role and responsibilities＞

• Development of the spacecraft AOCS (Attitude, Orbit and Control System) GNC (Guidance Navigation and

Control) systems, design and verification activities.

• Support system level activities, such as: developing mission CONOPS (Concept of Operations) , defining

FMECA (Failure Mode, Effects, and Criticality Analysis) and FDIR (Failure Detection, Isolation, and Recovery)

processes and design, system test and verification activities.

• Develop control law and algorithms – analysis, design, implement and validate (simulate) scenarios for RPO

(rendezvous and proximity operations) RPO & docking maneuvers.

• Develop GNC hardware and/or software architecture, towards an overall GNC solution.

• Support procurement engineers with trade-off and selection of GNC equipment.

<Mandatory Requirements>

• 3+ years of experience as an AOCS or GNC systems engineer involved in either of the design, implementation

and testing of GNC solutions for aerospace vehicles.

• Otherwise, 3+ years of experience on the mobile object dynamics control involved in either of the design,

implementation and testing, with major in aerospace engineering in undergraduate or graduate school in

university.

• Experience of algorithm & control law development: use of GNC design and simulation software e.g., MATLAB,

implementation of control laws and real world effects (non-linearities, signal noise, tuning), translating

algorithms into operational flight software.

• English language capability TOEIC 700+.

• Business level Japanese language capability.

<Desirable Requirements>

• 5+ years of experience as an AOCS or GNC systems engineer involved in the design, implementation and

testing of GNC solutions for actual spacecraft missions.

• Preferable to have experience of implementation of RPO and docking algorithms and solutions.

• Experience of hardware trade-offs and hardware and software GNC architectural design.