Andrzej Ratajczak
Kotlin Developer at JetBrains
Greater Poland Voivodeship
Summary
🤩
Rockstar🎓
Top SchoolAndrzej Ratajczak is a Kotlin developer with 7 years of JVM-focused engineering experience, currently working at VirtusLab and JetBrains. He has deep hands-on expertise in tooling and documentation engines, having contributed significant fixes and features to high-profile open-source projects like Kotlin/dokka and the Scala 3 compiler. His work spans backend development, test automation, and compiler-rendering improvements—most notably resolving complex Gradle/Android multi-flavor documentation issues and implementing interactive type-hierarchy diagrams for Scala 3. Comfortable navigating build systems and Gradle plugin integrations, he brings a pragmatic approach to improving developer tooling and docs generation. Based in Greater Poland and holding an MS in Computer Science from AGH University of Krakow, he combines academic grounding with practical OSS impact that’s often hidden behind polished SDKs and docs.
7 years of coding experience
3 years of employment as a software developer
Master of Science - MS Informatyka, Master of Science - MS Informatyka at AGH University of Krakow
Github Skills (18)
kotlin10
dokka10
java10
scala10
javas10
api-documentation10
compiler-design10
gradlew10
gradle10
markdown9
apidoc9
markdown-it9
api9
build-tools9
html8
Programming languages (9)
Github contributions (5)
Kotlin/dokka
Nov 2019 - Feb 2022
API documentation engine for Kotlin
Role in this project:
Back-end Developer
Back-end DeveloperContributions:106 reviews, 217 commits, 113 PRs in 2 years 3 months
Contributions summary:Andrzej primarily contributed to the `kotlin/dokka` project, which is an API documentation engine for Kotlin. Their work focused on resolving issues related to documentation generation, particularly addressing problems with Android multi-flavor documentation shadowing. The user modified code to extract configuration data from Gradle plugins, and also added abstract structures for MD/HTML comments and an MD parser. Additionally, they have performed various bug fixes related to the processing of different content.
apidokkaapi-documentationkotlinjavadoc
scala/scala3
Oct 2020 - Jan 2022
The Scala 3 compiler, also known as Dotty.
Role in this project:Back-end Developer
Back-end DeveloperContributions:324 reviews, 201 commits, 130 PRs in 1 year 3 months
Contributions summary:Andrzej primarily focused on enhancing the Scala 3 compiler, specifically by implementing a fully interactive hierarchy diagram. Their work involved modifications to the rendering engine (ScalaHtmlRenderer.scala), the page creation process (ScalaPageCreator.scala), and the diagram building functionality (DotDiagramBuilder.scala, InheritanceInformationTransformer.scala). The user also contributed to improvements in the project's documentation and incorporated a feature for hiding redundant type hierarchy diagrams.
compilerscala3scaladottyepfl
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