What Junio Hamano Reveals About 15 Years of Git Evolution

On April 7, 2020, a mailing‑list message was sent to the Linux kernel group announcing the 15th anniversary of the first Git tarball release.

Junio Hamano’s message: He thanks all contributors—code writers, documentation authors, legal helpers, and others—highlighting that software development involves many roles beyond coding. He notes that Git is a free‑software project supported by employers who allow contributors to work on it alongside their duties.

The email, titled “Happy Birthday,” was sent by Junio Hamano, a Google engineer, the main maintainer of Git and author of “Git 入门”.

Interview excerpt:

Q: How long have you been involved with Git, and what was your first impression? A: I joined about a week after Linus announced the first Git version in April 2005. I unpacked the tarball, read the code in a couple of hours, and was impressed by its simplicity and clarity.

Q: Why did you choose Git in 2005? A: I was already working on the Linux kernel and needed a robust version‑control system. Git’s patch and diff model fit my needs, and I wanted to help developers collaborate more efficiently.

Q: What was it like becoming the maintainer? A: I started as an individual contributor, waiting for Linus to officially pass the maintainer role to me. Early Git had many bugs, and development felt like a chaotic battle among many talented kernel engineers.

Q: Which Git feature are you most proud of? A: The rename and rewrite detection in the diff engine, which tracks changes across file boundaries, is a personal favorite. More broadly, I’m proud of how the community has grown and how contributors from diverse backgrounds collaborate.

Q: If you had a magic wand, what would you change? A: I would redesign the command‑line parsing for git rev‑list to avoid reusing diff syntax and make the index a hierarchical data structure rather than a flat one.

Q: How has Git changed the way developers build software? A: Distributed development allows developers to work privately and later publish snapshots, fostering better discipline. While tools alone don’t make programmers better, using a good tool like Git generally improves software quality.