It does reduce the competition of the "We provide Sentry as a Service" kind but it still allows people to create their own Sentry-like product of which they can also provide as a service.
I think for customers having different companies have their own approaches to solving this problem is vastly preferable to having different companies solve the same problem in exactly the same way.
They aren't closing their source though, just making it against the license to use it as a hosted service.
Example: Our company self-hosts sentry, this license won't effect us at all, we're still free to use and modify the source. We only use it internally - we don't sell "access" to it.
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This is cropping up more and more with various software companies. They _want_ to keep their source open. But people take the source, and just start selling it (Looking at you amazon) without actually contributing. It's one of those, "This is why we can't have nice things"
"Open source" has a definition, and they are removing their project from that open source definition. Even their own blog post acknowledges that they are no longer open source.
Saying that the source is "closed" seems a stretch though. Its certainly not free software any more. But even if it doesn't meet the official definition of open either (at least, for 3 years per contribution), there's still a lot of utility to be had.
Proprietary software with code that's viewable is actively harmful. It's worse than being closed. If you read the source, and use it (or a very similar version derived from it) in your code, you're including a copyright violation into your code.
You can still modify the code for personal and business use, as long as you’re not making money off of it, you’re fine. This is far better than it being closed source.
You can make money of it. You just can't use it to run a SaaS based on Sentry. This is a lot narrower than a general "non-compete" with a very minimal "non-commercial" restriction.
You can provide Sentry-as-a-service but you can't do so commercially.
You can use the Sentry code commercially but you can't use it to provide Sentry-as-a-service commercially.
But this restricts corporations from selling this as a service. Similiar to how some open source liceases require you to provide any modifications if you choose to reuse and modify.
They are still open source because the source is open.
Not every open source lic is like MIT where you can do whatever you want.
> They are still open source because the source is open.
That is not the definition of 'Open Source'. Using it interchangeably with 'open source' just adds confusion. And from the other uses of 'open source' in your comment, it seems you're using it in the same sense as 'Open Source'
> Not every open source lic is like MIT where you can do whatever you want.
No Open Source license allows you to "do whatever you want". Even the WTFPL, which comes close to that goal, is not an Open Source license. Being Open Source comes with a few requirements, which every Open Source license, licensor, and licensee must fulfill.
How's it different from AGPL? It seems like AGPL creates certain restrictions on the internal order of a company which uses AGPL code for the benefit of the AGPLed code's community. And this licence is basically the same.
Because the BSL flat out bans the use of the source code for a specific purpose for 36 months and mostly behaves like Apache-2.0 for most other intents and purposes, whereas the AGPL affects all users (commercial or non) and requires them to publish source code for all publicly accessible services using the AGPL licensed code, regardless of purpose.
If MongoDB were AGPL, both a company providing MongoDB-as-a-Service and a non-profit web app using MongoDB in the backend would equally need to publish their source code.
The BSL just says "you can't do this one specific thing for 36 months".
The AGPL is a more viral version of the GPL, which basically says "if your code uses this code, your code is now GPL licensed" and also "for all GPL licensed software you distribute, you must also make its source code available" (with the AGPL just redefining that "distribute" as "distribute or make accessible as a service").
I think for customers having different companies have their own approaches to solving this problem is vastly preferable to having different companies solve the same problem in exactly the same way.