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Fixing a Thread-Safety Bug with Nate Berkopec

Can you tell if a Ruby gem is really thread-safe or not? And how do you fix a seemingly thread-safety issue that can be something else entirely?

We had no idea. So we asked Nate Berkopec to help us. Nate is an expert in Ruby performance.

The verdict: nuking all shared global mutable state in your Ruby code is a bad idea if you don't know what you're doing!

Listen to this episode to learn:
- How and why faker-ruby became thread-unsafe, especially for Puma users
- Questions to ask yourself when trying to debug thread-safety issues
- Shared global mutable state is not always the villain, and is not the source of all thread-safety issues
- Nate's "watch-out" list of things that can cause undesired behavior when running multi-threaded Ruby applications: Constants, Class Variables, and Rack Middleware.

Episode Notes
🔗 Full transcript and links


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A special thanks to Valentino Stoll, nfstern02, and Gregg P for sponsoring hexdevs!

Enjoy!

Episode source