Thanks! Yes I think a caching solution like this is great for notebooks, because it makes it very cheap to re-run the whole thing (as long as you reasonably organized long-running computations into `@op`s), overcoming the notorious state problem.

Graphviz is indeed a lifesaver; and you can similarly think of `mandala` as a "build system for Python objects" (with all the cool and uncool things that come with that; serializing arbitrary Python objects with strong guarantees is hard https://amakelov.github.io/mandala/tutorials/gotchas/).

I've no experience with rust, but I'd be curious to hear about the difficulties that came up. I'd expect to see some overlap with Python!

What I can remember immediately:

1. Imports are more complex than in Python, because a module can be just a block in code, not necessarily a separate file/folder. E.g. `pub mod my_module { <code with functions and constants> }` is a module inside another module, so you don't need a folder and `__init__` inside to have inner modules.

Also, `use something` may man an external crate.

`use super::something` means import from upper level of modules tree, but it's not necessarily a folder.

2. I can parse what types my functions require in their signatures, or structs require in their members (but I must have resolved where really those names point at), but there's also type elision -- i.e. you don't need to explicitly write the type of every var, it's deduced from what is assigned, for example `let my_var = some_func(...)` -- will make `my_var` have the return type of some_func. Now I must also keep track of all functions and what they return.

And then, there are generics:

    let my_var: Vec<MyType> = vec![...];

Vec is generic, and in this case it has MyType inside. Well, this may be enough to just register `MyType` on my deps list. But then I may do some more calls:

    let my_other_var = my_var.pop().unwrap().my_method();

Here, `pop()` returns `Option<MyType>`, unwrap returns `MyType`, and then in the end, my_method may return whatever, and I essentially need something like a compiler to figure out what it returns.

This seems big like a little compiler or language server.