It doesn't use any helpers in its first article.

After that 90% of the articles only use code to compile shaders. The rest is raw.

At some point you have stop using raw OpenGL/WebGL. The point becomes to show how to apply the concepts, not focus on minutia of setting up things that were covered before.

AFAICT every article links to the articles it depends on and they all lead back to the issues that were already covered. Did you read the linked prerequisites or did you expected every article to have 10s or 100s of pages of repeated explanation?

This is no different than reading a book. If you jump to chapter 14 you can't complain it's not re-covering topics that were covered in chapters 1 through 13.