🦀 Compile-Time Reflection Is Finally Here
Today’s issue: Rust-Powered Safety Rolls Into Volvo, Rc::clone Hits a Performance Speed Bump, and Rust Jobs Are Having a Moment
Hello, Rustaceans!
In this issue, we’ll discuss a highly anticipated feature, present you a Rust tip, spotlight an amazing crate, and share 10 incredible links of the week.
Here’s issue 102
MAIN NEWS
Compile-Time Reflection Is Finally Here
Have you ever written a generic function and thought, “Man, how do I just ask the compiler, ‘Yo, what even is T?’ at compile time? I swear my life would be at least 42% less painful.” Yeah. That pain.
After four months of implementation and architectural decision, the Rust gods just dropped a shiny new nightly toy: std::mem::type_info.
This fresh experimental feature (gated behind `#![feature(type_info)]`) gives you actual compile-time reflection via a const function that spits out a `Type` struct describing… well, the type.
Right now it’s super MVP, mostly useful for tuples (think field counts, offsets, recursion into elements), with basic `TypeKind` variants like `Tuple`, `Leaf` (primitives), or `Other` (everything else that’s currenty shy).
You call `Type::of::<T>()` in a const context, and boom, you’ve got size info, kind, and tuple deets without any runtime cost or sketchy proc-macro gymnastics.
What’s cool? This is the first real step toward proper const-friendly introspection in std, meaning smarter generic code, better error messages, maybe even tuple unpacking or auto-derives that aren’t pure macro wizardry.
Problematic side? It’s very early, don’t expect struct fields, enum variants, or trait info yet.
The current implementation is basically “tuples or bust,” and everything else gets a polite shrug.
Still, it’s a massive signal from the lang team: reflection is coming, and it’s not going to be another 10-year internals thread.
For us devs, this matters because it inches us closer to writing generic code that feels less like fighting the borrow checker and more like… programming.
Imagine debug printers, serializers, or visitor patterns that actually know what they’re looking at without a forest of trait bounds.
Who knew self-reflection would arrive before half our 2026 TODO lists?
Huge kudos to Oli, Ralf, Boxy, Tim, Josh, and the whole crew who shipped this first MVP.
RUST TIP 🦀
Last week we had you solve the Group String Rotations challenge. Awesome of you jancha, and dotPE. Now, this week’s tip.
#[inline] on small hot-path methods in traits
pub trait FastHash {
#[inline(always)]
fn hash(&self) -> u64;
}Why?
When you have small trivial trait methods that are called in very hot loops, #[inline(always)] often gives bigger performance wins than the compiler would decide by itself (especially across crate boundaries).
Reference: https://doc.rust-lang.org/reference/attributes/codegen.html?referrer=grok.com#the-inline-attribute.
PROJECT SPOTLIGHT 💡
Tylax
Tylax is a high-performance tool that converts mathematical formulas, tables, full documents, and TikZ graphics between LaTeX and Typst formats.
What makes Tylax secretly awesome:
Actually bidirectional and structure-preserving Not just math formulas, it tries very hard to keep tables, sectioning, environments and general document skeleton readable on both sides.
TikZ → CeTZ conversion - The one feature everyone pretends they don’t desperately need until they do.
It also compiles to WASM if you enjoy pain in the browser.
Tylax is open-source and available on GitHub at https://github.com/scipenai/tylax.
AWESOME LINKS OF THE WEEK 🔗
The Rust Foundation Maintainer Fund Design Committee wrote What is maintenance, anyway? The Infrastructure Team also released their 2025 Q4 Recap and Q1 2026 Plan. Plus, the Vision Doc group published a new article attempting to answer: What does it take to ship Rust in safety-critical?
GRSH is an advanced Unix-like shell designed as an intelligent workflow environment that integrates native automation, AI assistance, and a modern terminal UI.
Jiayi Zhuang went digging into a Rust C parser and found the real villain: way too many Rc::clones. A rethink of state management later, boom, a casual 14% speedup. Turns out cloning “just in case” isn’t free.
Filtra’s Rust Jobs Report (December 2025) just released, and Rust hiring hit a fresh all-time high at 1,323 jobs.
TokioConf 2026 released its speaker lineup. If hearing Nicholas Matsakis, Glauber Costa, Alice Ryhl, and Steve Klabnik nerd out on stage sounds like your kind of fun, you know what to do, register and grab that ticket.
Jonathan Behrens just gave a fantastic talk at the Seattle Rust Meetup on Fast and Safe Image Decoding in Rust. [video]
Aapo Alasuutari’s Nova blog post on Garbage collection is contrarian explains why Nova’s JS engine should use contravariant lifetimes for GC handles, and for cleaner ergonomics, despite added complexity and unsafety.
Bevy v 0.18 is out, and yeah it’s stacked. Atmosphere Occlusion + better PBR shading? Chef’s kiss. Also: built-in fly/pan cameras and font variations, because quality-of-life matters.
Kampffrosch shows how to implement fast, stateful hot-reloading in Rust games using host/worker split + serialization.
Volvo Cars has shipped their first fully Rust-written ECU as part of the new SPA2 EV platform, a world-first in the automotive industry. Julius Gustavsson gave an awesome talk about it at NDC Conferences last week. [video]
CodeCrafters: Become a Better Rust Engineer
CodeCrafters created amazing Rust courses that push your skills beyond the basics.
You’ll have fun building real-world projects from scratch, including Git, Docker, Redis, Kafka, SQLite, Grep, BitTorrent, HTTP Server, an Interpreter, and DNS.
The courses are self-paced, so you can learn at your own speed.
Join for free and get 40% off when you upgrade. [affiliate]
SUPPORT RUST BYTES
You’re Rust Bytes’ biggest fans, and we love to see it.
❤️ Recommend Rust Bytes to your friends.
🤳 Connect with us on our socials: X, BlueSky, Mastodon, LinkedIn.
☕️ Buy our editors coffee.
📨 Email us at rustaceanseditors@gmail.com for sponsorship, feedback or ideas.
I’ve been working on being grateful for all the good things in life, it really helps keep overwhelm at bay.
I hope you can take a little time today to pause and feel thankful too.
That's all for now, Rustaceans.
John & Elley.