rtfeldman

8 ms·

1.
by rtfeldman 28d ago
I think the only language that's used in production where malicious dependencies can't do arbitrary effects is https://roc-lang.org - but it's a pre-0.1.0 language and as such its production usage is extremely min
2.
by rtfeldman 2mo ago
> Does roc run tests in the same process as the compiler? We do for tests of pure functions, yes. > Your tests run in an entirely separate process from the compiler (and from cargo). That's a great point and a relevant distinctio
3.
by rtfeldman 2mo ago
Also a good point! TIL that Rust and C++ use interpreters for const, although of course that wouldn't work for running tests. Then again, in the specific case of Rust I believe rustc only compiles the tests and then something else like
4.
by rtfeldman 2mo ago
> I think that for the hot binary patching / code reloading features, yes, that is going to need unsafe. But for regular old "producing an executable" compilation? Emitting machine code isn't the part that requires un
5.
by rtfeldman 4mo ago
Roc defaults functions to being pure, and functions that can run side effects are inferred to have a different type by the compiler based on usage. By convention, their names should also end in `!` (e.g. `transform` for the name of a pure f
6.
by rtfeldman 5mo ago
You can disable all AI features in Zed with a single setting: https://zed.dev/blog/disable-ai-features
7.
by rtfeldman 5mo ago
> The best at that that I've found is Conductor, but I can't use it at work because we only have Copilot and they're locked to a Claude/Codex backend. FYI, you can use Copilot directly in Zed!
8.
by rtfeldman 6mo ago
I maintain a ~250K LoC Zig compiler code base [0]. We've been through several breaking Zig releases (although the code base was much smaller for most of that time; Writergate is the main one we've had to deal with since the code b
9.
by rtfeldman 6mo ago
Very cool! The permission model is almost identical to Roc's - https://www.roc-lang.org/platforms - although Roc isn't designed for "Syntax only an AI could love" (among many other differences between th
10.
by rtfeldman 7mo ago
That's a much better test!
11.
by rtfeldman 7mo ago
If a stranger asks me, "Should I walk or drive to this car wash?" then I assume they're asking in good faith and both options are reasonable for their situation. So it's a safe assumption that they're not going ther
12.
by rtfeldman 7mo ago
> Whether functions are introduced with an explicit keyword; how return types are marked; whether semicolons can be omitted at end of line; how types are named (and the overall system for describing algebraic types). Yes, these are all e
13.
by rtfeldman 7mo ago
Wow, this is one of the most surprising comments I've ever read on HN! Personally, I bucket C++ and Rust and Swift under "basically the same syntax." When I think about major syntax differences, I'm thinking about things
14.
by rtfeldman 8mo ago
Claude Opus 4.5 is completely fluent in Zig. I use it constantly, and it never occurred to me that someone might think there was a problem to be solved there.
15.
by rtfeldman 8mo ago
Just based on timing, I am almost 100% sure whatever code is responsible was handwritten before anyone working on Windows was using LLMs...but anyway, thank you for the bug report - I'll pass it along!
16.
by rtfeldman 8mo ago
Definitely more than a faster keyboard (e.g. I also ask the model to track down the source of a bug, or questions about the state of the code base after others have changed it, bounce architectural ideas off the model, research, etc.) but a
17.
by rtfeldman 8mo ago
> Do you think it can replace you basically one-shotting features/bugs in Zed? Nobody is one-shotting anything nontrivial in Zed's code base, with Opus 4.5 or any other model. What about a future model? Literally nobody knows.
18.
by rtfeldman 8mo ago
Zed's entire code base is already open source, so Anthropic has a much more straightforward way to see our code: https://github.com/zed-industries/zed
19.
by rtfeldman 8mo ago
Anecdotally, we use Opus 4.5 constantly on Zed's code base, which is almost a million lines of Rust code and has over 150K active users, and we use it for basically every task you can think of - new features, bug fixes, refactors, prot
20.
by rtfeldman 10mo ago
If you're feeling adventurous and would like to try Roc's new compiler, I put together a quick tutorial for it! https://gist.github.com/rtfeldman/f46bcbfe5132d62c4095dfa687...
21.
by rtfeldman 11mo ago
My understanding is that the reasoning behind all this is: - In 1985 there were a ton of different hardware floating-point implementations with incompatible instructions, making it a nightmare to write floating-point code once that worked o
22.
by rtfeldman 11mo ago
> I’ve tried all the popular alternatives (Copilot, Claude Code, Codex, Gemini CLI, Cline) Can't help but notice you haven't tried Zed!
23.
by rtfeldman 11mo ago
As of August 2025, Zed had 150K monthly active users. That was before it supported Windows; the number is much higher now (although not publicly reported). I'd be very surprised to learn that any other Rust UI crate has more real-world
24.
by rtfeldman 11mo ago
You don't have to use Codex in its terminal UI - e.g. you can use it in the Zed IDE out-the-box: https://zed.dev/blog/codex-is-live-in-zed
25.
by rtfeldman 1y ago
When I wrote Elm in Action for Manning, I talked with them explicitly about the language being pre-1.0 and what would happen if there were breaking changes. The short answer was that it was something they dealt with all the time; if there w
26.
by rtfeldman 1y ago
> I get it, pausing some work to ship AI integration plumbing is a good strategy to keep momentum up with competition. By every metric - lines of code shipped, hours per week spent on it, number of people assigned to it, etc. - AI is a m
27.
by rtfeldman 1y ago
It's actively being worked on - there have been 8 font rendering PRs in the past 3 weeks, most recently yesterday: https://github.com/zed-industries/zed/pulls?q=is%3Apr+is%3Ac... A downside that comes with th
28.
by rtfeldman 1y ago
A quick glance at Zed's changelog is all it takes to see that AI has been a minority of what Zed has shipped since it was rolled out over a year ago. :) https://zed.dev/releases/stable (And that's even with a
29.
by rtfeldman 1y ago
We just pushed a fix! Here's how to get it: - Start a new Claude Code Thread, which will kick off the background download of the new Claude Code ACP adapter. - Wait a few seconds, then start another Claude Code Thread. The new thread w
30.
by rtfeldman 1y ago
Zed is open-source under GPLv3 - https://github.com/zed-industries/zed That doesn't guarantee it will have paid contributors indefinitely, but the same is true of the other editors you listed. It does, however, gu

More ›