For your use it may be more relevant to look at the .mpy version rather than the MicroPython version.

as you are building now, I would suggest to go no lower than .mpy v6 or v6.1 by default - that already gives a wide range (v1.20 and up).

Looking at the download stats for mpy-cross that range would likely cover the vast majority. (no guaranteed correlation with the active developers for natmods, but a likely related stat)

Dor the MicroPython stubs I do collect the (rather noisy) downloads stats from PyPI if you want a view of that may be useful to glean active MicroPython active development / version over a longer period.

https://github.com/Josverl/micropython-stubs/blob/main/statistics/month_version.png

The development of such tool began to be a quest how to resolve incompatibility. I solved natmod fully, it works simple and fine. I also solved support for esp32/windows/wasm/rp2 - fully. But I have difficulties with Unix now, I trying to use official pypa manylinux/musllinux docker images for cross builds but it still not fully covered.

But I have difficulties with Unix now, I trying to use official pypa manylinux/musllinux docker images for cross builds but it still not fully covered.

If I may ask, what is your goal, all tier 1 ports ? Is it ever possible to support all Unix/Linux flavours? You may need to set some bounds, in my limited understanding

But I have difficulties with Unix now, I trying to use official pypa manylinux/musllinux docker images for cross builds but it still not fully covered.

If I may ask, what is your goal, all tier 1 ports ? Is it ever possible to support all Unix/Linux flavours? You may need to set some bounds, in my limited understanding

All tier 1 ports is my goal

There is list of all that already builds

https://github.com/ballistics-lab/cibuildmp/actions/runs/33275435467/attempts/1#summary-99165910033

If I may ask, what is your goal, all tier 1 ports ? Is it ever possible to support all Unix/Linux flavours? You may need to set some bounds, in my limited understanding

I plan to cover:

• natmod builds all arches (done)
• usermod builds - at least tier 1, already handled rp2/stm32/wasm/windows/qemu/linux
• unix/linux usermod coverage now is the same as cibuildwheel provides. I use same pypa/manylinux vendored images or my own but nested FROM on pypa/manylinux
• Allow to build upstream micropython firmware from the upstream repo with no usermodules

You can find out how the build containers are grouped here https://github.com/ballistics-lab/cibuildmp/blob/main/docs/reference/vendored-images.md

The CLI and config were intentionally simplified compared to cibuildwheel, as the cibuildwheel model is rectangular and cannot cover the MicroPython distribution model, which has different nesting depths for different ports. So, the goal build/skip selectors model was chosen as a result of research and the rejection of cascade/tree-based models.

In any case, usermod is more complex to support than natmod, so it may have a lot of problems. But once you set up this tool once, its maintenance will start to simplify over time.

Currently, micropython upstream uses a lot of CI scripts tied to GitHub Workflows, and it still does not provide users or developers with a convenient way to build firmware for many targets simultaneously. Cibuildmp is inspired by cibuildwheel and is intended to at least partially solve this problem.
I have doubts that the micropython maintainers will want to take the project into micropython org. However, since I have limited time for active maintenance, I want to make the project useful enough so that it can be handed over to the community for further development.
I would be very interested to hear your feedback regarding the interest of the maintainers and active contributors in such a solution.

I found the real problem, it's an absolute mismatch of toolchain versions between ports and micropython versions. Is there some deterministic dependency across mpy versions?

I'm not a compiler specialist, but I think one reason for such variation actually might stem from the required SDKs and their toolchains.

possibly relevant: mattytrentini/build-micropython-arm-docker#3

I'm not a compiler specialist, but I think one reason for such variation actually might stem from the required SDKs and their toolchains.

possibly relevant: mattytrentini/build-micropython-arm-docker#3

Thanks anyway. I'm trying to make PoC changing architecture to use bootlin toolchains instead of system ones

I got some progress with cibuildmp. I even able to build lvgl usermod project.