Johannes Weiss
Senior Software Engineer - Distributed Systems (ICT5) at Apple
Stony Stratford, England, United Kingdom
Summary
🤩
Rockstar🎓
Top SchoolJohannes Weiss is a Senior Software Engineer with 17 years’ experience specializing in distributed systems and server-side Swift, currently driving backend reliability at Apple. He combines deep systems expertise—TLS, SwiftNIO, and HTTP stack work—with practical security-minded engineering, having refactored OpenSSL support and hardened certificate and key handling in swift-nio-ssl. Johannes is an active open-source contributor to high-profile projects like async-http-client, Vapor, and swift-corelibs-foundation, where his work ranges from lifecycle and shutdown correctness to threading and memory-fix patches and comprehensive tests. His background spans embedded to enterprise systems across startups and research labs, and he brings a knack for improving build processes, observability, and robust streaming/error handling that quietly prevents production surprises.
17 years of coding experience
12 years of employment as a software developer
Master's degree (Diplom Informatiker), Master's degree (Diplom Informatiker) at Karlsruhe Institute of Technology (KIT)
Stackoverflow
53,213reputation
11.4mreached
326answers
32questions
console
top-5%
sql
top-5%
java
top-1%
regex
top-5%
html-parsing
top-1%
command-line
top-5%
Github Skills (74)
postgresql10
python10
echo10
testing10
swift-nio10
http10
bash10
vapor10
terminology10
c1110
c1710
vim10
server-side-swift10
mtls10
javas10
Programming languages (17)
Github contributions (5)
swift-server/async-http-client
Jul 2019 - Sep 2022
HTTP client library built on SwiftNIO
Role in this project:
Back-end Developer
Back-end DeveloperContributions:4 releases, 104 reviews, 35 commits in 3 years 2 months
Contributions summary:Johannes primarily focused on enhancing the `async-http-client` library, which is built on SwiftNIO. Their work included ensuring proper shutdown procedures, modifying the lifecycle model to align with the parameters used, and incorporating a logger. They also added tests and made code style improvements.
http-clientswift-nioswift-serverswift5
apple/swift-log
Feb 2019 - Jun 2021
A Logging API for Swift
Role in this project:Back-end Developer
Back-end DeveloperContributions:4 releases, 45 reviews, 35 commits in 2 years 3 months
Contributions summary:Johannes primarily focused on improving the logging functionality of the Swift Logging API. Their contributions included refactoring the codebase to use `Logger.Message` struct instead of strings, allowing for string interpolations, and updating the logging levels. They also made some small code and documentation improvements.
loggingswiftswift-server
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.