Twenty years since the first commit
On 7 April 2005 Linus Torvalds makes the first commit of Git, a distributed version control system written to manage development of the Linux kernel after the break with BitKeeper. The goal is a system that is fast, distributed and resistant to data corruption. Twenty years later, Git is not just the dominant version control system: it is the invisible infrastructure on which the entire software development ecosystem is built.
The original architectural choices — a DAG of commits identified by SHA-1 hashes, immutable objects, lightweight branching and merging — have proved remarkably durable. The distributed model, where every clone contains the complete repository history, eliminated dependence on a central server and enabled workflows that centralised systems like SVN and CVS could not support.
The ecosystem built on Git
GitHub (2008), GitLab (2011) and Bitbucket transformed Git from a command-line tool into a collaborative platform. Pull requests, code review, integrated CI/CD, issue tracking: features that are not part of Git itself but exist thanks to its distributed model. The forge has become the gravitational centre of the software lifecycle, and Git is its underlying protocol.
The acquisition of GitHub by Microsoft in 2018 for $7.5 billion confirmed the economic value of the ecosystem built around Git. GitLab, with its complete DevOps approach in a single platform, created a parallel market where Git is the persistence layer for pipelines, infrastructure and configuration.
Scaling for enormous repositories
The most significant technical challenge of recent years is scalability for large repositories. Companies like Microsoft (with the Windows repository, hundreds of thousands of files) have driven the development of specific features. Sparse checkout allows downloading only a portion of the file tree. Partial clone avoids transferring the entire object history, downloading blobs on demand. Worktree enables working on multiple branches simultaneously without multiple clones.
The transition from SHA-1 to SHA-256 is underway, motivated by theoretical vulnerabilities in the original algorithm. The process is gradual and backwards-compatible, a testament to the complexity of modifying a data format adopted by billions of repositories.
A standard with no alternatives
Twenty years after its creation, Git has no real competitors. Mercurial, the most credible alternative, has been abandoned by nearly every project that used it. New systems like Jujutsu and Pijul explore different models but start from Git compatibility as a minimum requirement. Distributed version control is no longer a category of software: it is Git.
Link: git-scm.com