QtCS2024 Breaking The Monolith

Notes

Should we split qtbase even further than it is? Core separate from Gui
Should add-on modules support require only the last Qt LTS?
Whatever we do, we shouldn't lose our consistency in quality
- Compiler, platform requirements, C++ level, etc.
Danger: incompatible versions, if "max versions" exist
Danger: fragmentation of contributors' attentions
- Right now, we are "all in" for every release and we are all invested in all modules' quality

Bring back Qt Solutions - source-only releases

Source-compatibility only and mostly
Should be easy to integrate into existing projects (used to be just a .pri file, for qmake)
Issue is discoverability - Qt Market Place?

Installation and packaging

Maintanance tool should support installing things
- But shouldn't make things more confusing!
- Different version numbers going out-of-sync would be confusing
C++ doesn't have a good way outside of this, which makes things difficult for users
- This needs to be investigated first

Look at what the KDE Frameworks split and how the process went, pros and cons

Splitting too-fine-grained has a drawbacks, for users who need more than just a few
Dependencies become non-obvious
Left-over modules that become dumping ground because they weren't cleaned up
All modules still released in-sync

Use of private API is extensive in Qt between libraries

Too convenient, also difficult to change now without BC break
Intra-module dependencies may be OK, inter-module ones with different release cycles are not
Create an intermediate class between public and private API ("protected" API)
- Not as well documented
- Documented as meta-stable: stable for only a period of time, but may change beyond that

Is it fine right now?

Runtime dependencies are mostly ok already (no deploying of QtWidgets in Android apps for example)
Splitting further out or having different release cycles may be counter-productive
Does allow us to immediately use new APIs in all modules
- No waiting for the new content to have been present in the last LTS
- But isn't this what stable user applications already face?
But may be required for some modules, for other reasons
- qtwebengine is an example

Use the feature system more