Day 22 - Kafka Streams & First Open Source PR!

Diving deep into Kafka Streams and contributing to Apache Kafka OSS
Author

Shashank Hosahalli Shivamurthy

Published

July 10, 2025

Day 22 - Kafka Streams & First Open Source PR!

Today was all about Kafka Streams.

Yesterday, I spent the entire day investigating an issue on the Apache Kafka GitHub repo. So I woke up excited and pumped to continue.


Kafka Streams Learning

Started the Kafka Streams course from Confluent.

  • Understood the purpose, what problem it solves, and how it fits in the Kafka ecosystem
  • Built a simple Kafka Streams app that:
    • Consumed from a topic
    • Did some basic filtering
    • Produced to another topic
  • Ran everything on Confluent Cloud

Also experimented with configs and logs — this was super helpful because it directly related to the issue I was planning to work on.

Watched a Kafka Streams Architecture & Deep Dive talk from the Confluent YouTube channel and read the official docs, honestly really clean and clear. Great experience overall.


Open Source Contribution

After getting a good grip on Streams, I:

  • Read the codebase
  • Went through the issue in detail
  • Checked out an older PR where someone had worked on this but left it midway

All of this gave me great context.


Small Break + Personal Errands

Went on a run + short walk, Got a haircut and treated myself to a good dinner.

It was a sunny evening and I am glad I stepped out.


First Open Source PR

Came back home and worked more.

After hours of testing and debugging - finally, around 11PM, I opened my first ever Pull Request to the Apache Kafka GitHub repo.

Many more to come! Super excited about this journey.


This one’s a milestone. Lesssgooooo!!!