Really like the "state your assumptions out loud" move, it's the step juniors skip most. Two things that pair well with your 30-minute flow:
Write the numbers on the board, don't just say them. When you later choose a cache or a shard key, you can point back at "~1,200 read QPS" and the trade-off sounds reasoned instead of memorized.
Pick your deep-dive before the interviewer does. Around minute 15, say something like "the riskiest piece here is the feed fan-out, I'd like to spend the next 10 minutes there." It shows judgment and keeps you out of a random rabbit hole.
One small extra: close with a 30-second recap of what you'd change at 10x scale, since that's the last impression the interviewer writes down.
Really like the "state your assumptions out loud" move, it's the step juniors skip most. Two things that pair well with your 30-minute flow:
One small extra: close with a 30-second recap of what you'd change at 10x scale, since that's the last impression the interviewer writes down.
(Disclosure: I work on Linkjob AI interview assistant, a tool for interview practice and live help.)