What is the structure of the Internet projects Habrahabr, Smartprogress?

Question

Programming

Hey Habr!
There are many experienced programmers sharing their experience with beginners.
In this regard, it would be very interesting to know the structure of web projects - habrahabr.ru and smartprogress.do (very similar, at first glance).
From my current position, when you are just getting acquainted with basic programming languages, only the tip of the iceberg is visible - this is design, external layout, the basic structure with its user registration and the possibility of publishing materials.
If you are a software developer and have already implemented large projects, then what, in your opinion, is important in the development of such a web project? What nodes of the project allow you to start the project, so that you can then grind the details?
If you wish, you can write a detailed article on Habré, so as not to write the answer here exclusively for me.
Thank you for attention!

Answer 1

"The devil is in the details," say the Arabs. “God is in the details,” Christians say. Both are right. If you don't pay attention to details, the devil is hiding behind them. If you give them their due, God reveals himself in them.
You can contact the developers of both services and ask them directly :) And chat with their cockroaches.
They can start with any of the following topics
1. How the project came about: relevance, demand, user-centricity, satisfaction of needs, usability, and as a result the idea and design
2. How the development is carried out: collaborative development, version control systems, automated testing, automatic update
3. How they attracted users: SEO, advertising, engagement, retention
4. How they grew: growth orientation, scaling, redundancy, caching, optimization
5. How they communicate with users: feedback, user support, technical support
5. How they earn: paid services, customer acquisition and retention, commercial impact, experiments with users
6. How they manage the project: prospects, tasks, work planning, risks
These are all different aspects, but that's not all.

Answer 2

What nodes of the project allow you to start the project, so that you can then grind the details?

The main 3 turtles:
1. Router (+session controller) => Single entry point for all public requests.
2. forms (+ data validator) => "Conversation" of the system with the user. (registration, search, etc.)
3. database (CRUD and etc.) => Data warehouse.

Answer 3

Router, validator, database, compiler - it's all clear.
The visible part of the Internet resource is the design (control panel, links), content (publications), database (again, publications and users), etc.
The invisible part is probably (I don't know) the most difficult part of an Internet project. That's what lies there and in what structure?