Fly is building everything in hard mode - since they are not layering on top of an existing cloud like pretty much everyone else (heroku, render, railway, ...).<p>It's either very smart (if they pull it off) because they will have a ginormous cost advantage or they fail.<p>I'm personally of the opinion that the ux on top of aws/gcp/... is worse than a doo-doo in a shoe. However, they are as stable as can be (all complex systems go down once in a while). There are very few mature projects that do not rely on aws/gcp/... managed services anyway.
Might as well put in the little bit of effort to set yourself up for the future instead of painful migrations. This obviously doesn't hold for hobby projects.<p>In any case, I have a <i>lot</i> of respect for the engineering that fly does. Kudos.