Exactly. And there are tons of techniques to do so. For instance, Stripe is a payment service (you would think a payment service is the number one choice for tr

Exactly. And there are tons of techniques to do so. For instance, Stripe is a payment service (you would think a payment service is the number one choice for transactions/locks/etc right?) implemented on the good ol unreliable internet. you can look at how they do it (idempotency, etc) Transactions are a nice and convenient shortcut when they're applicable but they're far from mandatory.