Jakub Chaloupka
Principal Software Developer at Oracle
Brno, South Moravia, Czechia
Summary
🤩
Rockstar🎓
Top SchoolJakub Chaloupka is a Principal Software Developer at Oracle Labs in Brno with six years of professional experience focused on high-performance language runtimes and developer tooling. He contributes to GraalVM core projects—Graal, TruffleRuby, GraalPy and GraalJS—where his work improves native image builds, Java-language interop, and runtime performance and stability. Prior to Oracle he led engineering teams at NetSuite, blending hands-on backend development with team leadership. He holds an advanced computer science background from Masaryk University (PhD/MA) and brings research-grade rigor to pragmatic performance engineering problems. Notably, his open-source commits reveal a knack for subtle runtime fixes (stack-trace recovery, thread-local optimizations) and JNI/build-system integrations that reduce friction for polyglot native images.
6 years of coding experience
8 years of employment as a software developer
Doctor of Philosophy (Ph.D.), Computer Science, Doctor of Philosophy (Ph.D.), Computer Science at Masarykova univerzita Brno, Fakulta informatiky
Github Skills (20)
debugging10
debug10
javascript10
graalvm10
python10
image10
java10
ruby10
javas10
jna10
performance-optimization10
truffle10
testing9
jvm9
multithreading9
Programming languages (5)
Github contributions (5)
oracle/graaljs
Dec 2019 - Jan 2023
GraalJS – A high-performance, ECMAScript compliant, and embeddable JavaScript runtime for Java
Role in this project:
Back-end Developer
Back-end DeveloperContributions:34 commits, 7 comments in 3 years 1 month
Contributions summary:Jakub's commits primarily focus on developing and testing Java code related to JavaScript interop within the GraalJS runtime. Contributions involve creating tests for JavaScript array interop, modifying Java adapter bytecode generation, and adding Java-JavaScript interop benchmarks using JMH. The user's work includes implementing various interop scenarios, such as accessing JavaScript arrays from Java, and passing Java arrays to JavaScript.
polyglotnode-jscompliantjavascriptinteroperability
oracle/graal
Nov 2022 - Jan 2023
GraalVM compiles Java applications into native executables that start instantly, scale fast, and use fewer compute resources 🚀
Role in this project:Back-end Developer & Performance Engineer
Back-end Developer & Performance EngineerContributions:9 reviews, 20 commits, 30 comments in 2 months
Contributions summary:Jakub's contributions primarily focus on improving the performance and stability of the GraalVM project, with the commits addressing bugs and optimizations within the Truffle and Java runtime components. The user implemented fixes by including stack traces for possibly swallowed exceptions and also optimized various runtime aspects, such as thread-local actions and object size calculations. The commits also indicate debugging the Java runtime.
polyglotpythonjavascriptrubyanywhere
Find and Hire Top DevelopersWe’ve analyzed the programming source code of over 60 million software developers on GitHub and scored them by 50,000 skills. Sign-up on Prog,AI to search for software developers.