I usually have far lower server bills than my colleagues because i don't pick up saas when i don't need too. This is the an optimization that does save money :

I usually have far lower server bills than my colleagues because i don't pick up saas when i don't need too. This is the an optimization that does save money : knowing when to manually setup servers vs going aws/firebase/whatever. As for the doubled nested loops, as usual, it depends. Data size, boudaries, number of concurrent operations, cpu costs, acceptable loading time...