Since the @bunjavascript folks recently wrote about their experience moving from Zig to Rust, it seemed like a good time to write about our experience rewriting @roc_lang from Rust to Zig!
rtfeldman.com/rust-to-zig
rtfeldman.com/rust-to-zig
Jul 16, 2026 · 9:44 AM UTC
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@rtfeldman @bunjavascript @roc_lang Thanks for the post! I'm curious about the cold build timings. Are these in release or debug? And if debug, is this using LLVM for Zig, or their new custom backend? My mental model has been "Zig should compile faster in non-Release builds" so I'm curious if it's wrong.
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@zeuxcg @bunjavascript @roc_lang Debug for all of them, and it's the default (non-llvm) backend in Zig's case.
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@rtfeldman @bunjavascript @roc_lang Great write up! I appreciate the balance and nuance you brought. I hadn’t seen Andrew’s pointer free programming talk, will have to give that a watch. Roc is incredible.
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@rtfeldman @bunjavascript @roc_lang Given what you know today what would you have done different if you had the opportunity to do it again?
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@rtfeldman @bunjavascript @roc_lang Way to be a good example of how to present a good-faith pleasant post. People reading that will leave with good vibes for roc, rust and zig but an understanding of why you made the choices you did
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@rtfeldman @bunjavascript @roc_lang A very fair and practical write up!
Came across the zero-parse deserialization strategy a few months back in a data oriented design talk as well. Pretty interesting
Came across the zero-parse deserialization strategy a few months back in a data oriented design talk as well. Pretty interesting
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@rtfeldman @bunjavascript @roc_lang Nice read friend. Just wait till you see Jac, it very well may be the best language in the world, its cooking... give it a little bit more time. (unless of course you don't want to ;-))
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@rtfeldman @bunjavascript @roc_lang Open source is about trust. To me, the Roc team's approach seems to have earned that, unlike Bun. Looking forward to trying out 0.1.0.
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@rtfeldman @bunjavascript @roc_lang Hahaha, say about waiting for the right moment! Now you can farm the aura.
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@rtfeldman @bunjavascript @roc_lang This was a very good read even though I haven’t programmed in any of those languages. Makes me want to try both
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@rtfeldman @bunjavascript @roc_lang Why not self-bootstrapped compiler though? Won’t be it an another rewrite soon?
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@rtfeldman @bunjavascript @roc_lang Nice use of Perceus ref counting, looking forward to roc numbered release!
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