He has been mentioned in git log more than 20 times. Also, he is one of the active contributors of rbs: https://github.com/ruby/rbs/graphs/contributors.
Because he is not a committer yet, he is inaccessible to some development resources (like Slack workspace for Ruby committers), which is actually inconvenient not only for him but also for some of us (the committers).
I want to mention his contributions for more than one year and feature plans on RBS, in addition to the commits we can find in ruby repo.
His project for generating RBS files from Rails project, RBS Rails, is one of the key components to make RBS more useful in real-world Ruby projects.
He also has made many improvements on rbs prototype, which is a tool to generate RBS file prototype from unannotated Ruby programs. This also makes working with RBS more practical by giving a good starting point for writing RBS files.
He is now working for rbs collection command. It is a set of features to help using gem_rbs_collection, the community-managed RBS collection, and will be deeply integrated into the RBS command.
I believe he has made, and will make, a large impact on Ruby through RBS, and having a committer bit will make our collaboration more smooth (even though we can continue working with him without the bit technically).
The most interesting area is static typing. I work on RBS and related tools because I'd like to introduce static typing to real Rails applications. I believe static typing will improve the developer experience.
I'm also interested in the documentation improvements. I am a member of rurema, the Japanese Ruby documentation project. I'm porting rurema's patches to RDoc, such as https://github.com/ruby/ruby/pull/3251.
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