Day 107 of 133
Design TikTok / YouTube feed recommendations
Two-stage architecture; cold start; candidate-generation strategies.
DSA · NeetCode Stack
- Min StackDSA · Stack
Interview questions to prep
- How do you support getMin in O(1) — what's the auxiliary stack trick?
- Can you do it with a single stack of pairs, and what's the trade-off?
ML System Design · Recommendations
Interview questions to prep
- Walk me through designing TikTok's For You feed end-to-end.
- How would you handle the cold-start problem for a new user?
- What candidate-generation strategies would you use, and how do you combine them?
- How would the architecture change for a Pinterest-style visual discovery or Follow Pins system?
- What feedback-loop or popularity-bias mitigation would you add for a visual discovery feed?
Interview questions to prep
- Why do industrial recsys use a two-stage (recall + rank) architecture?
- How do you avoid training/serving skew between recall and ranking?
References & further reading