[adamb]

Security holes present an interesting challenge. Since we allow authors to blacklist their code at the uuid level, it's possible to issue a network-wide advisory that revokes execution rights for that specific uuid.

This can instantly close the hole until a patch is released. This keeps users safe and gives application authors time to test against their application with the new library before re-publishing.

In many cases, application authors are the only people that are qualified to test interactions between their applications and the updated library.

[adamb]

The distributed programmer in me wants to point out that having applications automatically use the latest version of a library is a scary proposition.

During a distributed operation, participants can arrive at many different points in time. This means that applications using the newly-patched library will likely be interacting with applications using the unpatched library. Whenever multiple versions of anything are interacting with themselves things can get complicated.

In light of this, we opted to keep things simple and predictable for ourselves (and others). Since applications always run against exactly what you say they should, you're free to keep running forward, without having to worry about tripping over past decisions.