Job Description: Department Overview The Company CIO Office is a newly established organization, launched in June 2025 under the direct lead of Rakuten Mobile's CIO. Its core mission is to address various issues related to IT systems and information assets by developing IT strategies and governance frameworks and subsequently implementing the necessary system developments. From the perspective of Rakuten Group's Communications & Energy Company, this department is undertaking a highly significant initiative to establish corporate governance across Rakuten Mobile. Furthermore, we foster a culture that values each employee's ideas and encourages proactive challenges. The IT Development Section is responsible for the planning, system development, and operation necessary to realize our company-wide IT strategy. Team members will be involved from the initial planning stages, participating in all phases of system development, from upstream conceptualization to downstream implementation. Furthermore, we actively incorporate the latest technologies into our development efforts, including planning and development aimed at promoting the internal use of AI. Position: Why We Hire We are significantly strengthening our organizational structure to realize Rakuten Mobile's IT strategy. This includes addressing various challenges that arise in business promotion and developing systems to improve operational efficiency using AI. Position Details You will be responsible for conceptualizing system solutions by carefully considering appropriate responses to challenges raised by various departments within Rakuten Mobile. As an Application Development Engineer, you will be involved in all phases of system development, from the initial planning stage to downstream implementation, including requirements definition, design, development, business process creation, and vendor management, all based on these conceptualized plans. Looking ahead, we envision you playing a key role as a future leader within the department. Work Environment Currently, the entire department consists of 16 members, with 2 in this section. However, we plan a significant expansion of the entire organization, including other sections, in the near future. Our existing team is primarily composed of mid-career hires, many with backgrounds in telecommunications carriers. While development is currently conducted on a SaaS platform, we plan to establish development environments tailored to future development needs. Mandatory Qualifications: - 5+ years of experience in application development (implementation) using languages such as Java, Python, and JavaScript - Experience in IT system construction - Ability to proactively identify issues and take action to resolve them Desired Qualifications: - Experience in mobile application (iOS/Android) development - Experience in QA (Quality Assurance) and QC (Quality Control) - Knowledge of databases (DB) and infrastructure Other Information: Additional information on Location Rakuten Crimson House (Head office) Additional information on Secondment Although your official affiliation will be with Rakuten Group's Company CIO Office, you will operate as a member of Rakuten Mobile's CIO Office, focusing on initiatives and support for Rakuten Mobile Additional information on English Qualification Proficiency in English sufficient for coordination with relevant departments is desirable TOEIC Score 800 above or possess equivalent abilities #engineer #applicationsengineer #communicationsandenergy In Japanese, Rakuten stands for ‘optimism.’ It means we believe in the future. It’s an understanding that, with the right mind-set, we can make the future better by what we do today. So we challenge ourselves to evolve, innovate and experiment, to create a better, brighter future for everyone. Today, our 70+ businesses span e-commerce, digital content, communications and fintech, bringing the joy of discovery to almost 1.3 billion members across the world. If you have any trouble logging in, please contact us here Rakuten Group, Inc.: rakuten-recruiting-info@mail.rakuten.com Please read the Application Requirements(EN) / 募集要項(JP) before applying. Our Diversity & Inclusion Policy and Application Documents Rakuten’s corporate mission is to “contribute to society by creating value through innovation and entrepreneurship.” We foster a culture that provides equal opportunities to those who share this founding philosophy and take on the challenge to transform society, regardless of age, gender, nationality, or any other status. Diversity is one of Rakuten's core strategies and a driving force for innovation. Because of this, you are not required to submit any of the following information in order to apply for our job positions. - Gender - Age - Photo - Nationality - Information not related to business, such as ideological beliefs, family structure, etc. * For legal compliance, we may ask you about your work eligibility. See the details