@jtojnar : i think all is good now ;)

Hmm, I am getting

/nix/store/sck8x99a3lsjlxwns4sgy1zaf8ll31hc-gvfs-1.38.1/lib/gio/modules/libgioremote-volume-monitor.so: undefined symbol: g_mount_operation_get_is_tcrypt_system_volume
Failed to load module: /nix/store/sck8x99a3lsjlxwns4sgy1zaf8ll31hc-gvfs-1.38.1/lib/gio/modules/libgioremote-volume-monitor.so

** (gst-plugin-scanner:9640): CRITICAL **: 12:18:04.914: pygobject initialization failed

This still fails to run for me:

Traceback (most recent call last):
  File "/nix/store/92wzfvip0pvkhzi44029hybm7vjmwxdh-gscrabble-unstable-2019-03-11/bin/..gscrabble-wrapped-wrapped", line 15, in <module>
    import gscrabble
  File "/nix/store/92wzfvip0pvkhzi44029hybm7vjmwxdh-gscrabble-unstable-2019-03-11/share/GScrabble/modules/gscrabble.py", line 11, in <module>
    gi.require_version('Gst', '1.0')
  File "/nix/store/bncy9d114kp08ln751f89qvgb674j6qf-python3.7-pygobject-3.30.4/lib/python3.7/site-packages/gi/__init__.py", line 129, in require_version
    raise ValueError('Namespace %s not available' % namespace)
ValueError: Namespace Gst not available

It seems the GI overrides from ${python3.pkgs.gst-python}/lib/python3.7/site-packages/gi/overrides are not being picked up.

I however don't know how the gio override magic works :-)

i've environment.variables.GIO_EXTRA_MODULES = [ "${pkgs.gvfs}/lib/gio/modules" ]; # lets PCManFM discover gvfs modules from https://nixos.wiki/wiki/Samba (that failed as all of this documentation on the wiki ) but perharps it covers me to see such bug. I should have a closer look at this. btw there is a lot of bugs about gi around, i'm not confident the problem is from my derivation ... i've gvfs-1.36 for information.

i've git rebase and fix things, hope it's good now.

Got it to run without erroring out, but the language selection seems to be buggy. I couldn't switch using something other than Arabic (or am to stupid to figure out where to click).

Any idea what fixed the Namespace Gst not available error now?

What about the version number? Readme in the upstream repo mentions 0.1.2, but there seem to be neither tags nor release tarballs. Could you ask upstream to make a release (maybe after the language selection is fixed)?

the language selection seems to be buggy. I couldn't switch using something other than Arabic (or am to stupid to figure out where to click).

Yes you need to fix in the preference, it wont work from start screen.

Any idea what fixed the Namespace Gst not available error now?

Can't be sure since i didn't have this problem with my old git tree. I think the alias gobjectIntrospection wont work but in my old tree, that was the official name.

What about the version number? Readme in the upstream repo mentions 0.1.2, but there seem to be neither tags nor release tarballs. Could you ask upstream to make a release (maybe after the language selection is fixed)?

If there is no tagged i take the latest that fix things for us ( RaaH/gscrabble#3 )
and since i've already 2 PR pending on this, i'll wait finish french translation and more worried bug without ask for a release. It took 7 months for jtojnar to have an answer ...

Well, I assume you'll maintain the package here and bump once the french translations or bugs are fixed, and take care asking upstream about a release ;-)

Started hitting the same issue as @jtojnar when trying to open a PDF with Zathura, which used to work just before the last channel update about 2 weeks ago.

/nix/store/cvzabqj2wiymkkrdw0l0mk6pw9rkdx4v-gvfs-1.40.1/lib/gio/modules/libgioremote-volume-monitor.so: undefined symbol: g_mount_operation_get_is_tcrypt_system_volume
Failed to load module: /nix/store/cvzabqj2wiymkkrdw0l0mk6pw9rkdx4v-gvfs-1.40.1/lib/gio/modules/libgioremote-volume-monitor.so

@FlorianFranzen looks like some kind of impurity. Please open a new issue.