You don’t have time to design everything — choose parts that show engineering judgment. Alex Wu’s notes emphasize focusing on the “hot path” and scalability bottlenecks. For the photo app, drill into:
Be explicit: “I’ll design upload + storage, and feed generation. I’ll assume auth and search are out of scope.”
Alex Xu’s books are famous for their blue/black architecture diagrams. Some GitHub users have recreated these diagrams using PlantUML, Mermaid.js, or Draw.io. These are excellent for practice because you can edit them for your own mock interviews.
You may have confused the name "Alex Wu" with Alex Xu. Alex Xu is the author of the best-selling series "System Design Interview" (often referred to as System Design Interview: An Insider's Guide).
Content: These books break down complex system design problems (like designing YouTube, Google Drive, or a chat system) into manageable steps.
GitHub Resources: While the books themselves are not legally available as free PDFs on GitHub, Alex Xu maintains a popular GitHub repository with system design resources.
The region where the Stin and Devos Rivers meet is populated by four duets of Warlords who are constantly battling for control of the region. The winning alliance of this struggle will dominate the region and control trade for four nations.
Underwaters
by siwego
Type Heroes 3 The Restoration of Eratia
Added 14-01-2018
Rating : 0 Rate this map
Download : 611
The geometry of the place was all wrong. One could not be sure that the sea and the ground were horizontal, hence the relative position of everything else seemed phantasmally variable.
- H.P. Lovecraft, The Call of Cthulhu
The Two People
by M Nielsen
Type Heroes 3 The Restoration of Eratia
Added 25-11-2017
Rating : 0 Rate this map
Download : 425
In this scenario 2 people living next to each other seperated by a river hate each other, so they now try to reach each other by any means possible and eradicate them
Underworld explor
by Klinno
Type Heroes 3 The Restoration of Eratia
Added 20-01-2018
Rating : 0 Rate this map
Download : 665
You and your allies are on a quest for the Royal Sphinx(Grail); will you succeed?
Or will your conquest come to a quiet ancient sleep as that of the Old Mummies Buried Deep Within Their Crypts.
Equal Opportunities
by Serge Trudolyubov, Alexander Degay, Andrei Kolobov
Type Heroes 3 The Restoration of Eratia
Added 16-01-2018
Rating : 0 Rate this map
Download : 593
It was peace. Until the day when the ruler of the underworld seized the Sword of judgement. Once other kingdoms and barbarians knew about it, Amolta turned ut to be in danger. This sword was a symbol of power and nobody dared to stand Amolt army led by a knight with the sword.
The Rise Of Infernex
by Brad Hayton
Type Heroes 3 The Restoration of Eratia
Added 28-08-2017
Rating : 0 Rate this map
Download : 530
You are Lord Argusia. You rule all of Tyria, But when the magical island of Snowden starts blowing out volcaniac ash clouds you know something is wrong.
Snowden was the jewel of Tyria but now its order is lost factions have arisen and it is up to you to claim back all of Tyria!
Subscribe to our Telegram Channel "maps4heroes.com" to be the first to receive NEW Maps and News for Heroes of Might & Magic 7, 6, 5, 4, 3, 2! 
