Is there a gem author around you? Did you meet any author of the gems used? Did you contact with any author of the gems used on the Internet? Do you think that "the author is cool!", "the author is awesome!" or "I respect the author!"? Do you want to be a gem author? This talk doesn't describe about how to create a gem because it is easy. "gem" is a package of Ruby library (, tool and so on) for easy to install. This talk describes about developing a library that is gem content. This talk is based on my experience as a library developer. This talk describes about how to write codes, how to write documents, release, support and mental set for a better "library developer". I hope that this talk is a trigger for increasing the number of better "library developers".

This talk describes three Ruby usages: * Implementing high-level interface by Ruby. * Using Ruby as a glue language. * Embedding Ruby into a C program for flexibility. All of them have pros and cons. They are trade-off. If a case can ignore cons, we will have pros for the case. Most of Rubyists implement their Ruby applications only by Ruby. This talk shows another options to use Ruby as your convenient tool. If you know another options and trade-offs of them, you will implement your Ruby applications more effectively. This talk uses Droonga, a distributed full-text search engine, as a sample application to describe these Ruby usages. Droonga uses these three Ruby usages.

This talk describes about the history of testing framework in Ruby. Ruby 2.2 bundles two testing frameworks. They are minitest and test-unit. Do you know why two testing frameworks are bundled? Do you know that test-unit was bundled and then removed from Ruby distribution? If you can't answer these questions and you're interested in testing framework, this talk will help you. This talk describes about the history of bundled testing framework in Ruby and some major testing frameworks for Ruby in chronological order.

This talk describes how to create Ruby bindings of a C library. It's the latest information in 2016.

Ruby's extension API is for C. This talk proposes C++ as a better language for extension API.

Here are my activities as a Rubyist: * Increase what Ruby can do with free software * Maintain libraries In this talk, I introduce my activities.

csv, one of the standard libraries, in Ruby 2.6 has many improvements: * Default gemified * Faster CSV parsing * Faster CSV writing * Clean new CSV parser implementation for further improvements * Reconstructed test suites for further improvements * Benchmark suites for further performance improvements These improvements are done without breaking backward compatibility. This talk describes details of these improvements by a new csv maintainer.

I introduced Ruby and Apache Arrow integration including the "super fast large data interchange and processing" Apache Arrow feature at RubyKaigi Takeout 2021. This talk introduces how we can use the "super fast large data interchange and processing" Apache Arrow feature in Ruby. Here are some use cases: * Fast data retrieval (fast (({pluck}))) from DB such as MySQL and PostgreSQL for batch processes in a Ruby on Rails application * Fast data interchange with JavaScript for dynamic visualization in a Ruby on Rails application * Fast OLAP with in-process DB such as DuckDB and Apache Arrow DataFusion in a Ruby on Rails application or irb session

ADBC is Apache Arrow Database Connectivity. It provides a API that can connect to different databases by wrapping database specific APIs. This is not a new approach. There are existing APIs such as Active Record, Sequel and ODBC. The difference between the existing APIs and ADBC is the focus on large data and performance. ADBC is an important part to use Ruby for data processing. We can extract large data from many databases (not only RDBMSs but also data ware houses and so on) and load large data into many databases with ADBC. To use Ruby for data processing, we need data. ADBC helps it.

I talked about ((<"Goodbye fat gem"|URL:https://rubykaigi.org/2020/presentations/ktou.html>)) at RubyKaigi Takeout 2020. Fat gem is a gem that includes pre-built binaries. Extension libraries can assume that users have build environment with Ruby 2.4 or later. So gems don't need to bundle pre-built binaries for easy to install. Users can build binaries by themselves. As of 2025, we're still using fat gem... I discussed how to improve this situation with ruby-installer author, Nokogiri maintainer and RubyGems community in 2022: * ((<"[RFC] Allow specifying and installing external dependencies"|URL:https://gist.github.com/postmodern/4c0cbccc0c7eda4585db0fc5267cdd57>)) * ((<"Standardize +requirements+ field from the specification rubygems/rubygems#1296"|URL:https://github.com/rubygems/rubygems/issues/1296>)) I propose a solution based on these discussions.

((<Apache Arrow|URL:https://arrow.apache.org/>)) is the de fact standard data format in modern data processing systems. We can use the official ((<Red Arrow|URL:https://rubygems.org/gems/red-arrow>)) gem to process Apache Arrow data. It's suitable for fast large data processing but it's over-performance for only low cost data exchange needs. Red Arrow is larger and a bit difficult to install than pure Ruby gems because Red Arrow is implemented as bindings. I'm implementing the official pure Ruby Apache Arrow reader/writer for only low cost data exchange needs. I expect that more Ruby libraries and applications add support for Apache Arrow inputs/outputs by the pure Ruby Apache Arrow reader/writer. Ruby can be used more for data processing by it. This talk describes how to implement fast pure Ruby binary data reader/writer and the future of data processing in Ruby. This is a 2025 Ruby Association Grant project: ((<URL:https://www.ruby.or.jp/en/news/20251030>))

Fat gem mechanism is useful to install extension library without any compiler. Fat gem mechanism is especially helpful for Windows rubyists because Windows rubyists don't have compiler. But there are some downsides. For example, fat gem users can't use Ruby 2.7 (the latest Ruby) until fat gem developers release a new gem for Ruby 2.7. As of 2020, pros of fat gem mechanism is decreasing and cons of it is increasing. This talk describes the details of pros and cons of it then says thanks and goodbye to fat gem.

To use Ruby for data processing widely, Apache Arrow support is important. We can do the followings with Apache Arrow: * Super fast large data interchange and processing * Reading/writing data in several famous formats such as CSV and Apache Parquet * Reading/writing partitioned large data on cloud storage such as Amazon S3 This talk describes the followings: * What is Apache Arrow * How to use Apache Arrow with Ruby * How to integrate with Ruby 3.0 features such as MemoryView and Ractor

Rubyで仕事をしているみなさんに自由なソフトウェアのことを知ってもらいたい！

この発表はミドルウェアの分野でもRubyの普及を促進することを目指します。Rubyで分散全文検索エンジンというミドルウェアを開発している経験から、Rubyで開発したミドルウェアを他の言語でのプロダクトと差別化するために気をつけるべきことを紹介します。この知見を使って、Rubyを活かしたミドルウェアがより多く開発されることを期待します。

2016年11月17日（木）開催の三木会でのMroonga紹介資料。

Droongaはまだ新しいプロダクトなのであまり情報がありません。今回はそんな Droongaを使いはじめる方法を紹介します。

2014年12月9日（火）21:00-22:00に実施する授業の資料です。今回は「3章 誤解されない名前」を読みながら、よい名前のつけ方について学びます。

2015年4月3日（金）21:00-22:00に実施する授業の資料です。今回は「7章 制御フローを読みやすくする」を読みながら、よりよい制御フローの書き方について学びます。

Apache Arrow is the future for data processing systems. This talk describes how to solve data sharing overhead in data processing system such as Spark and PySpark. This talk also describes how to accelerate computation against your large data by Apache Arrow.