85 - If It Compiles, the Agent Got It Right.
Agents are writing more of our code, and more of that code is in Rust. Prime Intellect let agents rewrite its coding agent in Rust and cut start-up from 736 ms to 52 ms. Niko Matsakis argues the type system is a big part of why agents do well in Rust, and Penguin Mail puts an opt-in assistant inside a native Rust mail client. When code gets cheaper to write, the compiler that checks the most becomes the sensible pick...
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ArtCraft Takes On Adobe With Twelve Rust Apps
Adobe's software was long seen as hard to compete with. But here we are. The ArtCraft team has announced twelve free, native creative apps written in Rust, from an image editor to CAD. There is no Electron and no web view, and most of them also compile to WebAssembly.
As a disclaimer only PhotoCraft and PdfCraft have reached alpha. PhotoCraft's README is the most concrete: its PSD support was written from Adobe's public specification and re-saves 307 of 309 psd-tools test files without changing the render. And it is good to know that the project itself says it is "not yet a Photoshop replacement for daily professional work". But it will just be a matter of time.
Niko Matsakis on What Agents Mean for Rust
Rust is an ideal language for coding agents. If the code compiles, there's a good chance it's correct. Niko Matsakis makes the same case in his post based on a talk at REBASE. In his words, Rust "happens to be a really good fit for agentic coding". The type system acts as guardrails, and agents are good at tuning fast code against a profiler.
He wants Rust to go further. "So my take is that Rust should double down on if it compiles, it works." That means a type system that can express more, so agents stop working around it. His north star is "no more unsafe code". The keyword stays, but tools like Verus would prove that unsafe code cannot cause undefined behavior.
Prime Intellect Let Agents Rewrite Its Coding Agent in Rust
More use of AI also means more use of Rust. If AI makes coding more cost effective and you still don't use Rust with its help, you are leaving a great opportunity on the table. Prime Intellect's rewrite of Prime Agent, its open-source coding agent harness, makes that case well. (By the way Google does the same read my previous email)
The team started in TypeScript. "TypeScript helped us ship Prime Agent quickly, but its types are optional and disappear at runtime," they write in the rewrite post. With agents writing most of the code, they wanted the compiler to carry more of the load. Exhaustive enums, Send and Sync, and Clippy's pedantic lints do that job.
Agents did write it, about 1,981 of them using 193 billion tokens. Each task went through a planner, an implementer, a reviewer on a different model and a verifier. Parity was checked by diffing terminal frames and session transcripts against the TypeScript binary.
The straight port did not win on its own. It was bigger on disk and slower at switching views. A three-day performance pass followed, mostly moving work off the startup path. After that, cold start to input-ready went from 736.1 ms to 51.9 ms. Memory on a large session fell from 1,130 MB to 237.3 MB.
Takeaways:
- Build the oracle first, before any agent writes Rust
- The result is nine crates with a one-way dependency graph enforced by Cargo, which keeps many agents from tangling one codebase
Penguin Mail Brings Rust and AI to Your Inbox
A lot of email is standard text and formalities, so why not combine both worlds, Rust and AI? Penguin Mail does that. It is mail, calendar and contacts for Linux and macOS, written in Rust on GTK 4 and libadwaita.
The assistant stays off until you choose a model. That can be a local server like Ollama or LM Studio, an OpenAI-compatible endpoint or the Anthropic API. It can summarise and draft replies, and it shows each tool call it runs on your mailboxes. Encryption goes through your own GnuPG, and there is no Penguin Mail server in between. The source is GPL-3.0-or-later.
Snippets
The state of SIMD in Rust in 2026 SIMD is getting more common as a speedup, so it is worth a look, or worth telling your AI to look at. Shnatsel compares autovectorization, portable libraries and raw intrinsics.
C for Rust Programmers A guide to C for people who learned Rust first. It covers null-terminated strings and array-to-pointer decay, and why fixed-width types like uint32_t beat long.
Compiling Rust to readable C with Eurydice From the Inria and Microsoft group behind Aeneas, Eurydice turns Rust into readable C for verification tools and targets with only a C compiler.
Tapo now speaks TP-Link's TPAP protocol The Rust and Python client for Tapo smart plugs and lights now supports TPAP, the SPAKE2+ login on newer firmware. It no longer needs the Third-Party Compatibility switch turned on.
Quake ported to safe Rust, playable in the browser 1996 Quake, ported from the WinQuake C source with
#![forbid(unsafe_code)]on every crate and no dependencies. Claude wrote the code, checked pixel by pixel.Deser: Rethinking Rust Serialization Armin Ronacher's experiment keeps Serde's ergonomics but inverts control. Formats push events into heap-allocated sinks, which avoids deep recursion and keeps what Serde loses with flatten and untagged enums.
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