Jul 21
Design a Coding Contest Platform like LeetCode
Design a coding contest platform that allows users to view problems, submit code, and compete in real-time programming contests.
4 min read
Writing24 posts · Since 2025
Notes on systems, LLMs, and the industry building them.
I'm Wenhao, a software engineer. I write up system design problems I've worked through, what I'm learning about LLMs, notes from shipping side projects like ResumeMatch, and the occasional take on layoffs and where the industry is heading.
Pinned
Jul 18
Design a online ticketing platform like Ticketmaster
Design an online ticketing platform that allows users to browse, purchase, and manage tickets for live events such as concerts, sports games, theater…
4 min read
Jul 18
Design a video streaming platform like YouTube
Designing a video streaming platform like YouTube is a classic and ambitious system design challenge.
3 min read
Jul 13
Spotify Top K Songs
Designing a system to identify the top k heavy hitters in a data stream is a common yet challenging system design interview problem.
3 min read
Jul 12
Key Concepts in System Design
Understanding core system design concepts is crucial for building scalable, performant, and reliable software systems.
4 min read
Jul 12
Design a Collaborative Document Editing System Liike Google Docs
Designing a collaborative document editing system like Google Docs is a common and challenging system design interview problem.
3 min read
Jul 10
Design a URL shortener like Bitly
Designing a URL shortener like Bitly is a classic beginner system design interview question.
2 min read