Go to GitHub, search "Grokking-ML-System-Design-Interview" , fork it, download the PDF summary, and print it out. Then, set a timer for 45 minutes and draw a "News Feed Ranking" system from scratch.

For those who prefer a structured, offline reading experience:

: A comprehensive guide focused on big tech (FAANG) roles. It includes a famous 9-step ML System Design Formula .

ML systems are moving to real-time. This repo explains exactly how to do feature engineering on streaming data (tumbling windows, sliding windows). You need this for "real-time fraud detection" questions.