[anonydsfsfs]

> Also, BLAKE3 is faster than MD5 and also far more secure, so if you're saying "It's okay I'm using MD5 because I want a faster hash and SHA-256 is too slow," there are options other than SHA-256.

True, but BLAKE3 isn't shipped as part of the standard library of many (any?) languages, whereas MD5 is. There are third-party implementations for a lot of languages, but using one of these brings up a lot of problems:

1. Are you sure the implementation doesn't have any bugs? AFAIK, the BLAKE3 team has only created C and Rust implementations, so anything else likely hasn't received the same level of care.

2. How are you going to notified of bugs or vulnerabilities in the implementation? For your language's standard library, it's usually easy to get notified of any bugs or vulnerabilities, but you're probably not going to get that from some random implementation on Github.

3. Pulling in the dependency can be an attack vector in itself. For example, if you use the Javascript implementation on NPM, you're now going to have worry about the NPM author having their account compromised and the package replaced with malicious code.

[geofft]

That's fair, I should have added that as an exception too. Another similar case: you're writing a shell script and you can assume the target machines all have md5sum installed but not necessarily b3sum.