The Qlty CLI is Fair Source

Licensing is a critical consideration for software developer tools. The Qlty CLI is the foundation of our code quality platform, and we knew from the outset that closed source and per-seat licensing fees were a non-starter.

Publishing the code publicly on GitHub allows us to run a community-driven development process in the open. Making the software free-as-in-beer makes it easy to adopt in any organization of any size without salespeople or credit cards. Both are essential for making the Qlty CLI the best and most widely adopted code quality tool for polyglot teams.

As a small business, we are committed to building a commercially sustainable, self-funded business that will secure continued investment in best-in-class code quality tools for developers over the long term.

With this in mind, we are excited to announce that the Qlty CLI's Rust codebase is licensed under Fair Source.

What is Fair Source?

Fair Source is an innovative licensing model that balances open access and commercial sustainability and is intended as an alternative to closed-source software.

The official website defines Fair Source Software with three criteria:

1. The code is publicly available -- in our case, on GitHub

2. The license allows free use, modification, and redistribution with minimal restrictions to protect the producer’s business model; and

3. After a delay, the code reverts to an OSI-approved Open Source license, also known as delayed Open Source publication (DOSP)

You can read more about Fair Source on their FAQ.

Our license choice

Like Open Source, Fair Source is an umbrella term. Various licenses meet the Fair Source criteria.

For the Qlty CLI, we are using the Business Source License 1.1 with delayed publication under the GNU General Public License (GPL). You can read the full license in the code repository.

We considered the Functional Source License (FSL), but it is written with permissive Open Source in mind, and only allows for Apache or MIT as future licenses. However, we felt that the GPL's copyleft protections provided value by ensuring that all future improvements to the CLI are made available to the whole community.

We are thrilled to see how the developer community will engage with the Qlty CLI under this new licensing model and look forward to the innovations it will inspire.