Design and operate reliable payment and financial systems, covering transaction integrity, recovery, compliance, cloud infrastructure, and new financial products. The role requires 5+ years of web application experience and leadership across multiple technical domains.
About this role
This internship focuses on developing Ruby itself rather than only building web applications. Participants receive direct mentoring from Ruby committers at STORES and investigate the mechanisms of the language while working on a selected technical theme.
Possible projects include improving parallel and concurrent processing through Ractor-compatible applications or libraries, prototyping an interpreter for a developing small-Ruby technology, improving the accuracy of the TypeProf static type analyzer, and reducing Ruby interpreter startup time. Participants may also propose their own project theme based on their interests and skills.
Candidates should have a strong interest in Ruby itself or in programming-language implementation and should have published some form of work in a GitHub repository, such as publicly available code. Applicants must be students at a high school, college of technology, university, graduate school, or vocational school; the field of study is not specified. A PDF resume and materials showing technical skills, such as a GitHub profile or portfolio site, are required for application.
The work may involve interpreter development, concurrency, static analysis, type inference, performance optimization, and open-source software. Code produced during the internship may be contributed to the Ruby open-source community. The internship is conducted with guidance from Ruby committers, including learning about design decisions and approaches to solving complex language-development problems.
The internship is held at the Shibuya, Tokyo office. It is offered on an ongoing basis with the timing adjusted to the participant’s preferences, and lasts approximately one month or longer. The participation reward is 2,000 JPY per hour. The employment arrangement is part-time employment with monthly renewals. The schedule uses a flextime system with core hours from 12:00 to 16:00 and standard working hours of eight hours. Tools listed for work include Google Workspace, Slack, Notion, and GitHub. An onboarding training session is provided on the first day. The selection process consists of a casual interview, document screening, one interview, and an offer.
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