Unable to install Seafile's server dependencies

Question

I'm trying to compile Seafile for Raspberry Pi and when I run sudo ./build.sh -DTA -v 9.0.9 -h https://raw.githubusercontent.com/haiwen/seafile-rpi/master/requirements/seahub_requirements_v9.0.9.txt -d https://raw.githubusercontent.com/haiwen/seafile-rpi/master/requirements/seafdav_requirements_v9.0.9.txt , per instructions, I always stumble upon the following error:

Collecting PyYAML~=5.1
  Downloading PyYAML-5.4.1.tar.gz (175 kB)
     ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 175.1/175.1 kB 40.6 MB/s eta 0:00:00
  Installing build dependencies ... done
  Getting requirements to build wheel ... error
  error: subprocess-exited-with-error
  
  × Getting requirements to build wheel did not run successfully.
  │ exit code: 1
  ╰─> [54 lines of output]
      running egg_info
      writing lib3/PyYAML.egg-info/PKG-INFO
      writing dependency_links to lib3/PyYAML.egg-info/dependency_links.txt
      writing top-level names to lib3/PyYAML.egg-info/top_level.txt
      Traceback (most recent call last):
        File "/usr/lib/python3/dist-packages/pip/_vendor/pyproject_hooks/_in_process/_in_process.py", line 353, in <module>
          main()
        File "/usr/lib/python3/dist-packages/pip/_vendor/pyproject_hooks/_in_process/_in_process.py", line 335, in main
          json_out['return_val'] = hook(**hook_input['kwargs'])
                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "/usr/lib/python3/dist-packages/pip/_vendor/pyproject_hooks/_in_process/_in_process.py", line 118, in get_requires_for_build_wheel
          return hook(config_settings)
                 ^^^^^^^^^^^^^^^^^^^^^
        File "/tmp/pip-build-env-pq42uacg/overlay/local/lib/python3.11/dist-packages/setuptools/build_meta.py", line 325, in get_requires_for_build_wheel
          return self._get_build_requires(config_settings, requirements=['wheel'])
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "/tmp/pip-build-env-pq42uacg/overlay/local/lib/python3.11/dist-packages/setuptools/build_meta.py", line 295, in _get_build_requires
          self.run_setup()
        File "/tmp/pip-build-env-pq42uacg/overlay/local/lib/python3.11/dist-packages/setuptools/build_meta.py", line 311, in run_setup
          exec(code, locals())
        File "<string>", line 271, in <module>
        File "/tmp/pip-build-env-pq42uacg/overlay/local/lib/python3.11/dist-packages/setuptools/__init__.py", line 103, in setup
          return distutils.core.setup(**attrs)
                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "/tmp/pip-build-env-pq42uacg/overlay/local/lib/python3.11/dist-packages/setuptools/_distutils/core.py", line 185, in setup
          return run_commands(dist)
                 ^^^^^^^^^^^^^^^^^^
        File "/tmp/pip-build-env-pq42uacg/overlay/local/lib/python3.11/dist-packages/setuptools/_distutils/core.py", line 201, in run_commands
          dist.run_commands()
        File "/tmp/pip-build-env-pq42uacg/overlay/local/lib/python3.11/dist-packages/setuptools/_distutils/dist.py", line 969, in run_commands
          self.run_command(cmd)
        File "/tmp/pip-build-env-pq42uacg/overlay/local/lib/python3.11/dist-packages/setuptools/dist.py", line 963, in run_command
          super().run_command(command)
        File "/tmp/pip-build-env-pq42uacg/overlay/local/lib/python3.11/dist-packages/setuptools/_distutils/dist.py", line 988, in run_command
          cmd_obj.run()
        File "/tmp/pip-build-env-pq42uacg/overlay/local/lib/python3.11/dist-packages/setuptools/command/egg_info.py", line 321, in run
          self.find_sources()
        File "/tmp/pip-build-env-pq42uacg/overlay/local/lib/python3.11/dist-packages/setuptools/command/egg_info.py", line 329, in find_sources
          mm.run()
        File "/tmp/pip-build-env-pq42uacg/overlay/local/lib/python3.11/dist-packages/setuptools/command/egg_info.py", line 550, in run
          self.add_defaults()
        File "/tmp/pip-build-env-pq42uacg/overlay/local/lib/python3.11/dist-packages/setuptools/command/egg_info.py", line 588, in add_defaults
          sdist.add_defaults(self)
        File "/tmp/pip-build-env-pq42uacg/overlay/local/lib/python3.11/dist-packages/setuptools/command/sdist.py", line 102, in add_defaults
          super().add_defaults()
        File "/tmp/pip-build-env-pq42uacg/overlay/local/lib/python3.11/dist-packages/setuptools/_distutils/command/sdist.py", line 251, in add_defaults
          self._add_defaults_ext()
        File "/tmp/pip-build-env-pq42uacg/overlay/local/lib/python3.11/dist-packages/setuptools/_distutils/command/sdist.py", line 336, in _add_defaults_ext
          self.filelist.extend(build_ext.get_source_files())
                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        File "<string>", line 201, in get_source_files
        File "/tmp/pip-build-env-pq42uacg/overlay/local/lib/python3.11/dist-packages/setuptools/_distutils/cmd.py", line 107, in __getattr__
          raise AttributeError(attr)
      AttributeError: cython_sources
      [end of output]
  
  note: This error originates from a subprocess, and is likely not a problem with pip.
error: subprocess-exited-with-error

× Getting requirements to build wheel did not run successfully.
│ exit code: 1
╰─> See above for output.

note: This error originates from a subprocess, and is likely not a problem with pip.
error: Thirdparty requirements installation failed

I've tried all kinds of things without success. It looks like the issue might be the lack of Cython support but I seem to keep getting this error even though I supposedly installed it.

I'm still a fairly newcomer to Linux so please provide steps I can follow.

Thanks in advance!