My Confluent loop, tail -n and temp email SD

My Confluent loop, tail -n and temp email SD

Just wrapped my Confluent loop, 3 rounds, figured I'd share since not much is out there about their process.

First coding round was tail -n, print the last N lines of a file using a given file API (read N bytes, move pointer, get size). Had to stream the output instead of holding it all in memory. Decent discussion on buffer vs pointer tradeoffs.

Second round was sensor health, wasAlive(key, start), checking if a sensor stayed active in a time window. Brute forced it then optimized with binary search.

SD was the temp email system, 100M users, mostly about generating realistic usernames and fast dedup checks.

Passed the two coding rounds, SD felt shakier. Still waiting to hear back.