Which Qt version for open source project?

agarny · 30 Nov 2022, 06:10

Hi,

I have a Qt-based open source project. For many years, I used to rely on the LTS version of Qt. That approach worked great until Qt 5.12 LTS, but around that time the Qt team decided to give up on open source developers.

So, right now, if I wanted to use the latest LTS version of Qt, I understand that I would have to use either Qt 5.15.2 LTS for the Qt 5 branch or Qt 6.2.4 LTS for the Qt 6 branch. I have seen here that Qt 5.15.6 LTS is now available to open source developers, but it's not through the maintenance tool. So, does it mean that one has to build it from source? If so, this is not an option for me, not to mention that, if anything, I would rather use the Qt 6 branch.

So, what do you, open source developers, do nowadays when it comes to the version of Qt to use? I feel like Qt is not good anymore for open source projects, which is very frustrating when you have spent so many years using it (very) successfully.

Alan

Christian Ehrlicher · 30 Nov 2022, 07:05

@agarny said in Which Qt version for open source project?:

So, what do you, open source developers,

Latest Qt 5.15 or latest Qt6 depending on if the program was already ported to Qt6 or not.

agarny · wrote on 30 Nov 2022, 07:05

@Christian-Ehrlicher said in Which Qt version for open source project?:

Latest Qt 5.15 or latest Qt6 depending on if the program was already ported to Qt6 or not.

Yes, when I first started with Qt, I used to use the latest version that was available, but I got bitten so many times that I eventually decided to use their LTS since it didn't bite as much (but still did on occasions). Argh, I really wish they would be more considerate of open source projects. I work in an academic environment and we just can't afford a commercial license. 😕

Christian Ehrlicher · 30 Nov 2022, 07:58

Then stay with one version until you really need new features.

agarny · wrote on 30 Nov 2022, 07:58

@Christian-Ehrlicher said in Which Qt version for open source project?:

Then stay with one version until you really need new features.

I don't really need new Qt-specific features, but I do need bug fixes / improvements in some areas. For instance, Qt 5.12 has various minor UI issues on recent versions of macOS and that's fair enough since it doesn't officially support those versions of macOS. That's why I feel like I might be better off upgrading to Qt 5.15 or, better, Qt 6. I just wish that I could get access to an LTS that is not crippled.

Anyway, I have just installed Qt 5.15.2, 6.2.4, and 6.4.1 and will give them a try and see how it goes. Just not impressed with the path taken by Qt. I used to recommend Qt all the time, but not anymore, unfortunately.

SGaist · 30 Nov 2022, 19:19

@agarny Since you mention academics, maybe the Qt educational license might me of interest.

agarny · S SGaist 30 Nov 2022, 08:39

@SGaist said in Which Qt version for open source project?:

@agarny Since you mention academics, maybe the Qt educational license might me of interest.

Yes, I remember looking into it, but... it says that "the license is for learning purposes only" and that "sharing and distribution of the created applications [is] allowed for learning purposes only". Well, this is not the case with my software since it is used by researchers, both in academia and in the industry. So, it looks like I wouldn't qualify for the educational license...?

SGaist · 30 Nov 2022, 21:32

Indeed then maybe the small business.

agarny · S SGaist 30 Nov 2022, 19:52

@SGaist said in Which Qt version for open source project?:

Indeed then maybe the small business.

Hmm... not sure that a University qualifies as a small business and, as a university, I would expect my employer not having a "combined revenue and funding equal to or less than two-hundred and fifty thousand ($250000) USD".