Building package on Launchpad is skipping to include .so files in the target package

I created a PPA to package the Helix-Editor: https://launchpad.net/~maveonair/+archive/ubuntu/helix-editor.

The build process completes successfully (logs) and the package is released. But for some reason, the package does not contain the *.so files created during the build step, which are needed at runtime to display proper syntax highlighting.

What confuses me, if I do the following on my machine (Ubuntu 22.04) then it will create a package that contains these files:

$ fakeroot debian/rules build
$ fakeroot debian/rules binary

$ dpkg -c ../helix_22.12-3\~ubuntu22.04\~ppa1_amd64.deb | grep grammars
drwxr-xr-x root/root         0 2023-01-14 13:28 ./var/lib/helix/runtime/grammars/
-rw-r--r-- root/root     51424 2023-01-14 13:28 ./var/lib/helix/runtime/grammars/astro.so
-rw-r--r-- root/root    338144 2023-01-14 13:28 ./var/lib/helix/runtime/grammars/awk.so
-rw-r--r-- root/root    559328 2023-01-14 13:28 ./var/lib/helix/runtime/grammars/bash.so
-rw-r--r-- root/root     30648 2023-01-14 13:28 ./var/lib/helix/runtime/grammars/bass.so
...

Here is the step that installs the *.so files "/var/lib/helix/runtime/grammars": https://github.com/maveonair/helix-debian/blob/main/debian/rules#L24

Does anyone have any idea what I'm doing wrong or why the package created on my machine is different from Launchpad's?

There was not a problem with the package itself, but rather with the lack of internet access during the build process of the binary on Launchpad.

I fixed the problem by adding all the additional source files to the Debian folder and then compiling the grammars for Helix during the "debian/rules build"-step.