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.

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.

Apache Arrow is a cross-language development platform for in-memory data. You can use Apache Arrow to process large data effectively in Python and other languages such as R. Apache Arrow is the future of data processing. Apache Arrow 1.0, the first major version, was released at 2020-07-24. It's a good time to know Apache Arrow and start using it.

2014年のSEゼミの「プログラミングが好きな学生のためのリーダブルコード勉 強会」のまとめ。

2014年のSEゼミの「プログラミングが好きな学生のためのリーダブルコード勉 強会」の課題の進め方を練習する方法の説明。

2014年のSEゼミの「プログラミングが好きな学生のためのリーダブルコード勉 強会」のアイスブレイクの仕方の説明。

2014年のSEゼミの「プログラミングが好きな学生のためのリーダブルコード勉 強会」の進め方の説明。

2014年のSEゼミの「プログラミングが好きな学生のためのリーダブルコード勉 強会」のグループふりかえりのやり方の説明。

2014年のSEゼミの「プログラミングが好きな学生のためのリーダブルコード勉 強会」のコードチェンジのやり方の説明。