[melony]

Go, Rust, and JS are unique in having package management solutions that prevents the diamond dependency problem. Most other languages suffer from the same problems as python in that they cannot have more than one version of the same package globally. The dependency resolution algorithms for Ruby/Dart/Julia are all NP class and require constraint solving which often fails to find a solution if your dependencies are complex.

[DougBTX]

For what it’s worth, the Poetry version solver works in the same way as Dart’s: https://github.com/python-poetry/poetry/blob/286f4ddb70394dd...

[brundolf]

You can face the diamond problem in NPM, it just deals with it internally (usually by installing both versions under node_modules). But I don't see that as related to whether dependencies are project-specific or system-wide