Ask HN: Is there any repo includes any “Hello World” projects you want?

I'm seeking for a git repo which has successful "hello world" templates for anything. Examples: an OpenGL project displaying simple triangle, an OpenCV project reads a png file and applies a simple filter, an HTML5 project which has style.css and app.js which have 3-4 lines of code, a very simple node server, a java project having only main method and System.out.println() inside it.

If there is no project like this? or I'm planning to start. Each project might have it's own repo and can be unified under a repo with submodules. This could be a useful resource if anyone wants to start a new project. Also, I want to know if anyone wants to join so we can build together.