Lightning Talks

MetricsMonitor is a gem that visualizes the internal metrics of ruby processes.

What are the CPU utilization trends for each process of a program that launches multiple processes? What is the timing of GC execution and how is the memory usage trending? How many Ruby objects of what class are being generated inside each process?

Therefore, I created MetricsMonitor, a tool that attaches directly to a running Ruby program and can observe its internal state. By simply embedding this tool in your Ruby program, you can visualize and observe the internal state of your program. This tool has been instrumental in visualizing and resolving real problems, such as bloated memory usage in large applications.

In this talk, I will show how my MetricsMonitor visualizes the internal state of a Ruby program and how I find problems in Ruby programs based on that visualization.

This talk will be enjoyable for Ruby developers who are looking to gain deeper insights about their Ruby applications.

An introduction how to use Ruby on the frontend instead of JavaScript. We will look at how to make apps with HTML, CSS and Ruby, which run on the web and on the desktop.

In the field of programming, there is a discipline called "Creative Coding," which involves creating art using code. It's not just about still images; you can also create videos, interactive pieces, and works where the outcome varies each time they're executed. While programming is often pursued to solve specific problems, Creative Coding involves programming as a means of expression, simply for one's own enjoyment. Creative Coding like that is achievable with Ruby as well. Why not add some color to your daily life with a little coding for yourself? In this lightning talk, everyone in the audience will get to experience Creative Coding firsthand :)

Ripper has longstanding bugs like Bug #10436. The root cause of the bug is the limitation of Bison. However we can fix the issue now. Only on the Lrama.

rubocop-daemon was developed independently as a personal project before being integrated into the RuboCop core as a Server Mode. In this LT, I will discuss how rubocop-daemon came into being and the process leading to its integration into the RuboCop core, sharing the lessons learned along the way. Specifically, I will focus on the challenges faced as an OSS project owner and the effective strategies for engaging with OSS projects.

In the Ruby on Rails development, ensuring comprehensive test coverage through proper specification is very important. However, amidst the rapid pace of development, we skip writing some test cases realistically. Therefore, leading to the potential risk of releasing unverified methods. Omochi solves this pain point. Omochi leverages static analysis techniques to scrutinize Ruby codebases and identify methods that lack associated spec files. By using static analysis, Omochi parses the AST of Ruby code, enabling it to traverse through the codebase and pinpoint methods without accompanying specifications. This approach eliminates the need for manual inspection of spec files, streamlining the process of ensuring comprehensive test coverage. In this presentation, I will delve into the potential for further efficiency gains in Ruby programming through static analysis techniques. I hope that Omochi will serve as a catalyst for the adoption of static analysis approaches in the Ruby community.

How I learned to stop worrying and contributed the Ruby parser.

REXML is a standard XML library (Bundled Gem) for Ruby, implemented in Ruby.

Pure Ruby is easy to install, but has the problem of slow processing performance. I rewrote this REXML parsing process with StringScanner to speed up the process.

Coverage is useful in many ways. It can detect code that isn't executed in production and also helps identify unnecessary tests based on the changes in pull requests. In this presentation, I will show how I used Coverage library to find hotspots in code execution.

Coverage は何かと便利です。本番で動かして実行されないコードも検出できますし、過去のテスト実行履歴から変わったコードに使われたテストを絞ることも可能です。この発表ではコード実行のホットスポットを探すためにカバレッジを使ってみた話をします。

Electronics projects often come with the daunting task of setting up development environments, which can deter many from getting started. However, as Rubyists, we have PicoRuby and the software implemented with it, called R2P2. With R2P2, you can embark on electronics projects by simply writing Ruby code in your editor, no setup required. This Talk will introduce you to the basics of electronic projects using R2P2 and showcase how to create a functioning RC car using this technology. Learn how effortlessly you can bring your code to life and drive an RC car, bridging the gap between software and hardware with Ruby's simplicity and power.

A programming language is made of two things: the language itself and its community. There is plenty of documentation about the first one, but how much do we know about the second? In order to find out more about the Ruby community, I interviewed Ruby programmers all over the world for a major research project at the University of London for a period of 2 years. I listened to their stories and tried to understand how Ruby shaped the way they code and see the world. I dug into online archives, explored old codebases, and learned about the myths and legends of the Ruby world. In this talk, I reveal what I learned as an anthropologist and researcher of the nicest coding community of them all.