Kengo TODA

I am an enterprise Java application developer. I'm also playing with JavaScript and Rust.
Motivated to make daily hacking enjoyable with build automation, CI, static analysis and virtualization.

FOSS Products

Unofficial GitHub Action for ReadTheDocs

Tackle routines work around doc-review in pull requests

Documentation with ReadTheDocs is really nice, because It lets us integrate documentation process to development workflow. This GitHub Action automates several tasks around documentation review, to encourage team to collaborate.

Jan 2021 - Present

new SpotBugs Gradle plugin

The official Gradle Plugin to run SpotBugs on Java and Android project

Developed a new Gradle plugin (v4.0.0) from scratch. It supports latest Gradle API like cachable task, lazy configuration, task config avoidance, and worker API for performance.

Mar 2020 - Present

gradle semantic-release plugin

Yet another gradle-semantic-release-plugin that invokes Gradle wrapper script to release

Bring semantic-release even to the Gradle project. Best match to library project that needs to follow SemVer2 and automate the release process for rapid development lifecycle.

Mar 2019 - Present


An OSS clone of

A playground to code with new technologies and best practices. It uses spring-boot, spring-webflux, selenide, Gradle, Checkerframework, Google Errorprone and docker-compose.

Jun 2017 - Present

What is Maven (ebook written in Japanese)

Introduction for Japanese newbies

An opensource ebook based on GitBook. You can get free copy at GitBook, or purchase at Amazon's Kindle Direct Publishing.

Jun 2017 - Present


The spiritual successor of FindBugs

Contributing as a core member, mainly working on bugfix, documentation, archetype for plugin developers, build on GitHub Actions, deploy onto Maven Central, deploy onto Eclipse update site.

Nov 2016 - Present

FindBugs Plugin, SonarQube Plugin & Errorprone Plugin for SLF4J

Static Analysis Tools for SLF4J users

Personal projects that helps SLF4J users to find misusage of logging API. With these tools, you will not miss the important log and data that can be easily missed by human errors like placeholder mismatch. It also contributes to improve readability of log messages, by eliminating non human readable message.

Nov 2012 - Present

Guava helper for Java 8

Migrate your code from legacy Guava to Java 8

Personal project that provides library for Google Guava Collection to work with Java 8 Stream API. It also provides SpotBugs plugin and SonarQube plugin, to detect usage of legacy parts in Guava like Optional.

Jul 2015 - Feb 2021

Jenkins Regression Report Plugin

Report newly created enbugs from tons of failing test

This plugin sends a mail if your test cases find regression (new failure). It is useful when your project has many failing tests and developers have got used to ignore them.

Jun 2012 - Apr 2016


Notice when follower removes you

A web service to notice you when followers remove/block your twitter account. It worked on Google App Engine (Java) and appengine-mapreduce. Analysis part is kicked by cron via TaskQueue, and runs on Backends. It used Twitter4J to check diff of followers, and send direct message to users.

May 2010 – Jan 2012


Programming Languages & Tools
  • Managing Cross Functional Teams, based on the culture of FOSS
  • Continuous Integration with Maven, Gradle, npm, Jenkins, Travis CI and GitHub Actions
  • Maintainable code based on DI, spring-boot and Selenium/Selenide
  • Performance tuning for RDBMS, KVS, server-side application and web pages
  • Agile Development & Scrum


I like hacking, especially static code analysis that supports stability and scalability of daily development. I also developed several plugins for Maven, Jenkins, SpotBugs, SonarQube, Google Errorprone, GitHub Actions and more to make daily hacking comfortable.