How a PHP request actually runs: PHP-FPM, OPcache and timeouts
PHP still starts every request from nothing, as it did in 1995. How nginx, PHP-FPM and OPcache work, and why they explain most PHP performance problems.
Backend
When the numbers don't agree, trust is the first thing to go. Backend work as correctness the business can rely on: APIs, business rules and integrations.
Handling money in software: why floats will eventually cost you
How the Vancouver Stock Exchange lost half its index to a rounding rule, and how to store, round and convert money correctly in any stack.