Read it once.
Reference it
forever.
Two libraries, both indexed by topic. The first is how I think about real systems on a whiteboard, written down with Mermaid diagrams. The second is 160 DSA problems with the solution next to it—not as a copy-paste, but as an explanation.
51 deep dives
Each document covers a real architecture problem the way I'd whiteboard it: requirements, the components I'd reach for, the flows between them, and the trade-offs. With diagrams.
- Distributed systems14 docs
- Realtime & messaging9 docs
- Storage & data11 docs
- Capstone designs17 docs
160 problems
Each problem opens with the statement, has a solution tab with the actual approach explained, and a tests tab so you can verify your own attempt. No locked content.
- Two-pointer & sliding window24 problems
- Trees & graphs53 problems
- Dynamic programming28 problems
- Misc · stack, hash, heap55 problems
Browse by topic
· How to use this
Three ways I'd actually use this library.
Before an interview
Pick the system-design topic that matches the company. Read the doc, walk through the diagram out loud, then close the tab and try to redraw it from scratch on paper. That's it.
During a real build
When you're choosing between two approaches at work, search the library for the closest pattern. Read what trade-offs I called out. Decide. Move on. The library is reference, not religion.
As a daily DSA habit
One DSA problem a day. Write your own solution first, then open the solution tab to compare, then run the tests. Twenty minutes a morning beats six hours on a weekend.
Reading isn't enough. Watch the videos too.
The video programs cover the same territory in a different texture—me explaining as I draw, with the rabbit holes and second-thoughts left in.