architecture Designing a Real-Time Leaderboard: Why Sorted Sets Beat a SQL ORDER BY at Scale josedacruz, September 16, 2026September 16, 2026 TL;DR: A leaderboard looks like a simple feature — sort some scores, show the top N — but a plain SQL table falls over once you have millions of players updating scores in real time. The fix isn’t a bigger database, it’s a different data structure: a sorted set (like… Continue Reading
architecture How Distributed Locks Actually Work (And Why They’re Harder Than They Look) josedacruz, August 5, 2026August 5, 2026 TL;DR: A distributed lock stops two servers from doing the same risky thing at the same time, like selling the last concert ticket twice. The tricky part isn’t getting the lock — it’s what happens if the worker holding it crashes, freezes, or runs slower than expected. Get the timeout… Continue Reading