Buried in this nicely-detailed RCA is a pretty damning fact:

Cloudflare left .unwrap() in mission-critical Rust code.

For non-Rustaceans, .unwrap() handles a type called Result that can either be Ok with a value, or an Err with an Error. The whole point is to gracefully handle errors and not let panics make it to production code. But unwrap() assumes there's a value to extract without safeguards.

I use .unwrap() sometimes! Usually when there's a logical guarantee that the result can never be an error. But I make sure to purge it from critical processes for exactly this reason.

https://blog.cloudflare.com/18-november-2025-outage/

@mttaggart I feel like all programming languages toe the line between being too permissive and everything breaks or too conservative and nobody uses it. For what it's worth I think rust does a good job striking this balance.

this is cloudflares fault and I really hope no one focuses their "this must never happen again" energy at Rust.

@fl0und3r 100% agreed. This is not a Rust problem and anyone who thinks Rust is supposed to prevent all programmer error misunderstands how programming works