There is an effort right now to produce a Devuan based OS that uses Maemo libraries (hildon and things for example) and can be run on various bits of hardware (with both the N900 and Neo900 being suggested as targets)

The idea of moving to a new OS base with modern kernel and libraries (ones that get fixes for any security flaws they may contain) is a good one but the way its being done by that team doesn't make sense.

I see the software stack for the N900 and Neo900 containing the following things going forward:
1.Replacements for old Maemo Fremantle packages taken from Devuan or elsewhere that are modern, up-to-date and still maintained and which are ABI compatible with Maemo
Fremantle/support the hardware we have in the N(eo)900 (or can be modified to be ABI compatible and support the hardware we have without a lot of work). So, newer kernel, newer libraries, things like that.

2.Replacements for Maemo packages that aren't a direct replacement but still do the same job. So, newer browser that isn't a direct clone of microb but still does what a browser for the N(eo)900 needs to do, new WiFi stack based on wpa_supplicant that replaces the old Maemo stack, things like that.

3.Existing maemo-specific FOSS packages (be they originally FOSS or be they cloned by someone) that are maintained and fixed (including security issues) going forward (this may include porting such packages to newer versions of various libraries). So, hildon stuff, status bar widgets, control panels, hardware daemons, things like that.

4.Older versions of FOSS libs that we need to keep around to keep existing binaries running. So, older openssl that we need for certain binaries, old browser engine that we might need for rtcom-mesasging-ui or nokia-maps, things like that.

5.Binary packages distributed by Nokia as part of Maemo Fremantle (where cloning those packages or otherwise replacing them just isn't an option or where we want that functionality in the short term but plan to replace it completly in the long term). So, cellular services daemon on N900, dialer app, messaging app, nokia maps, things like that.

and 6.Packages distributed by 3rd parties be they FOSS or otherwise that we want to be able to install and run as-is without needing to change them. So, things in extras-*, things on Garage, things on the forums, things like that.

Could you explain what exactly doesn't make sense and what is done differently to what you think it should be?

I was mostly talking about the armhf thing but FMG says there is no real reason the new work needs to use armhf at all and that switching to armel is trivial so that's sorted.

In regards to libraries on the N900, the libraries we have on the N900 fit into several categories:
1.Libraries where we have a newer modern maintained version that is ABI compatible with the Fremantle version (e.g. libc) or that can be modified/forked to be ABI compatible (e.g. I suspect GTK2 fits in this category)
2.Libraries specific to Maemo where we can keep the same ABI (e.g. hildon or e.g. various closed-source libraries we are keeping around)
3.Libraries where the version on Maemo is obsolete and there is a newer maintained version and its possible to have both libraries side-by-side on the one system (e.g. openssl)
4.Libraries where the version on Maemo is obsolete and there is a newer maintained version and its not possible to have both libraries side-by-side on the one system. (this should not happen since the Linux convention is that you bump up the library version and create a new .so file any time you do something that breaks the ABI)
and 5.Libraries that can/will go away because they are no longer needed due to changes elsewhere

Then please edit your comment, as it sounds impolite to the guys doing the really hard work for the last couple of months (if not more).

Why Devuan? What is wrong with Debian?

I guess not having Systemd is a good thing.

Yeah, that sounds like a much better base for me as well (bigger community, know track record, the actual origin of Freemantle, etc.). Also the Librem guys apparently want to choose Debian as well.

Do you have any concrete things in mind where using Systemd would be an issue ?

Systemd (and journal) has been used by Mer/Sailfish OS from day one and I really can't remember any Systemd specific problems during all those years.

Yes but the thing is, you want to be rid of systemd.
Take it from someone who's paid job is to work with systemd!