--- title: Ferrocene 26.05.0 now available! | daily.dev description: Ferrocene 26.05.0 is now available, the latest release of the TÜV SÜD-qualified Rust toolchain for safety-critical development. Key additions include a new... canonical: https://daily.dev/posts/ferrocene-26-05-0-now-available--ylnkb994l twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Ferrocene 26.05.0 now available! | daily.dev og:description: Ferrocene 26.05.0 is now available, the latest release of the TÜV SÜD-qualified Rust toolchain for safety-critical development. Key additions include a new... og:url: https://daily.dev/posts/ferrocene-26-05-0-now-available--ylnkb994l og:image: https://api.daily.dev/og/posts/ylnKb994l.png og:image:alt: Ferrocene 26.05.0 now available! og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Ferrocene 26.05.0 now available! **[Ferrous Systems](https://daily.dev/sources/ferroussystems)** · 6 min read · 5 upvotes · 0 comments ## Summary Ferrocene 26.05.0 is now available, the latest release of the TÜV SÜD-qualified Rust toolchain for safety-critical development. Key additions include a new `#[warn(ferrocene::unvalidated)]` lint for tracking certified vs. uncertified code usage directly in the IDE, certified `core::fmt` and `panic!()` macro support, limited `-C target-cpu` support for Cortex-M4 and Cortex-A53, and a new qualified `aarch64-rhivos2-linux-gnu` target in collaboration with Red Hat for software-defined vehicles. The release incorporates upstream Rust changes from versions 1.93.0 through 1.95.0. Ferrocene is ISO 26262 (ASIL D), IEC 61508 (SIL 3), and IEC 62304 (Class C) qualified, and is available at €25/month per user. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What new lint does Ferrocene 26.05.0 add for certified core usage? Ferrocene 26.05.0 introduces the #[warn(ferrocene::unvalidated)] lint, which warns when code uses uncertified library functions. Users add #![warn(ferrocene::unvalidated)] to their codebase instead of relying on a separate certified core package or custom target. Functions can be marked safe with #[ferrocene::prevalidated], or explicitly opted out with #[allow(ferrocene::unvalidated)], and warnings appear live in IDEs like Zed. _Rust teams tracking safety-critical tooling changes can follow releases like this one on daily.dev._ ### Is core::fmt certified in Ferrocene 26.05.0? Yes, core::fmt and the panic! macro's formatting machinery are certified as of Ferrocene 26.05.0. Previously the certified core subset lacked core::fmt, making panic! output and general debugging harder. Now developers can use panic!("At the {place}") in safety-critical Rust code with the same formatting experience as on a standard Linux distribution. _Developers weighing safety-critical Rust tooling upgrades can track changes like this via daily.dev._ ### What new target does Ferrocene 26.05.0 support for automotive use cases? Ferrocene 26.05.0 adds a qualified aarch64-rhivos2-linux-gnu target, built in collaboration with Red Hat for the Red Hat In-Vehicle Operating System used in software-defined vehicles. Alongside this, a qualified aarch64-unknown-linux-gnu host platform is being rolled out, though for this release it is only qualified when targeting aarch64-rhivos2-linux-gnu. _Engineers evaluating Rust for automotive safety platforms can keep up with target support on daily.dev._ ## Similar posts on daily.dev - [Rust core library partly polished for industrial safety spec](https://daily.dev/posts/rust-core-library-partly-polished-for-industrial-safety-spec-kvgfypftu) · The Register · 8 upvotes · 1 comments - [Ferrous Systems Achieves IEC 61508 \(SIL 2\) Certification for Rust Core Library Subset](https://daily.dev/posts/ferrous-systems-achieves-iec-61508-sil-2-certification-for-rust-core-library-subset-cwr2ymfeu) · Ferrous Systems · 1 upvotes · 0 comments - [Ferrocene for Air-Gapped Environments](https://daily.dev/posts/ferrocene-for-air-gapped-environments-derm4yuh9) · Ferrous Systems · 1 upvotes · 0 comments - [Recent Rust Changes](https://daily.dev/posts/recent-rust-changes-iaytt6tvw) · Nick Cameron · 9 upvotes · 0 comments - [Announcing Rust 1.97.0](https://daily.dev/posts/announcing-rust-1-97-0-fqxhq3pfj) · Rust · 22 upvotes · 0 comments --- Tags: [#rust](https://daily.dev/tags/rust), [#embedded](https://daily.dev/tags/embedded) [View this post on daily.dev](https://daily.dev/posts/ferrocene-26-05-0-now-available--ylnkb994l) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Ferrocene 26.05.0 now available!","url":"https://daily.dev/posts/ferrocene-26-05-0-now-available--ylnkb994l","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/ferrocene-26-05-0-now-available--ylnkb994l"},"datePublished":"2026-07-30T11:37:09.349Z","dateModified":"2026-09-14T08:43:14.046Z","description":"Ferrocene 26.05.0 is now available, the latest release of the TÜV SÜD-qualified Rust toolchain for safety-critical development. 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