# What's New in Rust 1.85 through 1.87

Page: https://stenobird.com/podcast/rustacean-station/what-s-new-in-rust-1-85-through-1-87
Text version: https://stenobird.com/podcast/rustacean-station/what-s-new-in-rust-1-85-through-1-87.md
Podcast: [Rustacean Station](https://stenobird.com/podcast/rustacean-station)
Published: 2026-01-22T16:55:10+00:00
Episode link: https://rustacean-station.org/episode/rust-1.85-1.86-1.87/
Audio file: https://dts.podtrac.com/redirect.mp3/audio.rustacean-station.org/file/rustacean-station/2026-01-22-rust-1.85-1.86-1.87.mp3
Processing state: processed
JSON: https://stenobird.com/v1/public/podcasts/rustacean-station/episodes/what-s-new-in-rust-1-85-through-1-87
Duration seconds: 4442

## Resource

A deep dive into the technical advancements in Rust versions 1.85 through 1.87. The discussion covers critical changes to async closures, target feature attributes, and supply chain security via Cargo.

## Highlights
- Main idea: Async closures now allow for more intuitive lifetime capturing and different trait implementations compared to previous async-returning closures
- Practical takeaway: Use the new target feature attribute on safe functions to allow safe calls within specific CPU feature sets like AVX
- Failure mode: The compiler now enforces non-null debug assertions for pointers to prevent common dereferencing errors in debug builds
- Main idea: Cargo now supports generating Software Bill of Materials (SBOM) to enhance supply chain security and transparency
- Practical takeaway: New Windows terminal integration for Cargo provides visual progress indicators in the taskbar during builds

## Topics

Rust Programming, Async Closures, Cargo, Software Supply Chain, Systems Programming, Compiler Features, Software Bill of Materials, CPU Instruction Sets

## Chapters
- 1:00 — Rust 1.85 and Async Closures: An introduction to the 1.85 release and the technical distinction between async closures and closures that return futures.
- 6:35 — Advanced Lifetime Bounds: Discussion on higher-rank lifetime bounds and their impact on asynchronous function signatures.
- 17:25 — Waker Optimization and Pointer Safety: Exploring Waker::nop to avoid unnecessary Arcs and new debug assertions for non-null pointer checks.
- 22:55 — Const Stability and Float Operations: Updates on the stabilization of const functions for size and alignment calculations.
- 34:30 — Target Feature Attributes: How the target feature attribute can now be applied to safe functions under specific conditions.
- 51:15 — Cargo Enhancements and SBOM: New capabilities in Cargo for generating SBOMs and improved terminal integration for Windows users.

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## Transcript

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