by sunshowers | 2025-10-16 20:20:54+00:00
Thank you for the kind words and the thoughtful response.

I'm deeply sympathetic to your viewpoint, and some days I certainly feel like Rust is creaking under its own weight. Why does your typical backend web service need all this complexity with borrows and lifetimes and manual memory management?

But allow me to present the other side of the argument. My background is in systems-level developer tools, and Rust has a combination of things that no other programming environment has:

* & and &mut, which enforce a rigorous separation between mutable and immutable state. I think this is the single most important feature of Rust, and the closest analog to this in other environments is purely functional languages like Haskell

* enums with data + exhaustive pattern matching; the latter is something even Haskell lacks

* high-level idiomatic code that performs like low-level code (e.g. iterators): Rust achieves this through an extraordinary combination of monomorphizing and inlining

* working in memory-constrained environments: tracing GC tends to have significant memory overhead, and I've worked in server environments where a big limiting factor was the amount of DRAM being produced globally

* good polymorphism: I think OOP is a suboptimal paradigm that breaks under day-to-day development stress. I've written about it at https://news.ycombinator.com/item?id=42512629

* fast startup times: this is a requirement for command-line tools people use hundreds of times a day—I spent many years working on Mercurial where Python's slow startup time was a very common complaint

* first-class support for using native OS calls directly; many higher-level languages like Java abstract away the details, so things like signal handling are hard to hook into

* first-class Windows support: again, non-negotiable for many developer tools, since the plurality of developers are on Windows

* and last but not least, a great dependency ecosystem, which ties into all of the above points: & and &mut mean that some transitive dependency three levels down won't suddenly alter the list you pass in, idiomatic performance means that perf regressions are rare, first-class Windows support means most dependencies just work on Windows, and so on

Is it possible to have an application-level/GCd/managed language that meets most or all of these requirements? Certainly. Does such an application-level language exist today? No, and there's nothing on the horizon either (Haskell has its heart in the right place, but is missing many of the more practical features here).

Rust isn't a great application-level language, but it's the best application-level language. And given how high the barrier tends to be for a new language to reach adoption, I'll probably be retired long before something like that shows up.

And yeah, async really is quite confusing in so many ways, and it's really unfortunate that this situation has seen no improvements in so many years. And yet, through its characteristics combined with the other things listed here, it enables developers to solve real problems that are completely infeasible in any other language.

So I keep trying to make Rust better :)