Staging passed, production broke. Why does staging always lie and what do you actually do about it?

Staging is a snowflake maintained by accretion. Rank drift sources by risk, shrink them mechanically with parity by construction, and stop calling staging the last line of defence.

Grounded in researched DevOps, SRE and platform engineering interview loops, written to a senior-engineer editorial bar, and never padded to hit a word count.