docs(standards): add blog post for rust language support

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: matthew-on-git

content/blog/2026-03-04-rust-support.md

@@ -0,0 +1,74 @@
+---
+title: "Rust Support"
+date: 2026-03-04
+description: "DevRail now supports Rust -- clippy, rustfmt, cargo-audit, cargo-deny, and cargo test ship in the dev-toolchain container."
+---
+
+Rust is the eighth language ecosystem in DevRail. Add `rust` to your `.devrail.yml` and the full toolchain is available immediately.
+
+## What Ships
+
+The dev-toolchain container includes the complete Rust toolchain and five tools:
+
+| Concern | Tool | What It Does |
+|---|---|---|
+| Linter | clippy | Official Rust linter, treats warnings as errors |
+| Formatter | rustfmt | Official Rust formatter |
+| Security | cargo-audit | Scans `Cargo.lock` against the RustSec Advisory Database |
+| Security | cargo-deny | Enforces license, ban, and source policies on dependencies |
+| Tests | cargo test | Built-in test runner, all targets |
+
+The entire Rust toolchain -- rustup, cargo, rustc, clippy, and rustfmt -- is COPY'd from the `rust:1-slim-bookworm` builder stage. Clippy and rustfmt are rustup components, tightly coupled to the compiler version. Shipping them together eliminates version drift between the linter, formatter, and compiler.
+
+cargo-audit and cargo-deny are installed via [cargo-binstall](https://github.com/cargo-bins/cargo-binstall) in the builder stage, avoiding long compilation times for these tools.
+
+## How It Works
+
+```yaml
+# .devrail.yml
+languages:
+  - rust
+```
+
+```console
+$ make check
+✓ lint       (cargo clippy --all-targets --all-features -- -D warnings)
+✓ format     (cargo fmt --all -- --check)
+✓ security   (cargo audit, cargo deny check)
+✓ test       (cargo test --all-targets)
+✓ scan       (trivy, gitleaks)
+```
+
+`make fix` runs `cargo fmt --all` to auto-format in place.
+
+## Gating
+
+Each tool gates on the presence of the files it needs:
+
+- **clippy and rustfmt** gate on `*.rs` files
+- **cargo audit** gates on `Cargo.lock` -- skipped if no lock file exists
+- **cargo deny** gates on `deny.toml` -- skipped if no policy file exists
+- **cargo test** gates on `*.rs` files + `Cargo.toml`
+
+This means Rust tools run only when there is Rust code to check. A multi-language project that declares `rust` but has not yet added any `.rs` files will not fail.
+
+## Pre-Commit Hooks
+
+The template repositories include commented hooks using [pre-commit-cargo](https://github.com/AndrejOrsula/pre-commit-cargo):
+
+```yaml
+- repo: https://github.com/AndrejOrsula/pre-commit-cargo
+  rev: v0.4.0
+  hooks:
+    - id: cargo-fmt
+      args: ["--all", "--", "--check"]
+    - id: cargo-clippy
+      args: ["--all-targets", "--all-features", "--workspace", "--", "-D", "warnings"]
+```
+
+Security scanning and tests remain CI-only due to execution time.
+
+## Get Started
+
+- [Rust standards reference](/docs/standards/rust/) -- configuration, Makefile targets, and notes
+- [Container tool versions](/docs/container/versions/) -- exact versions shipped in the current image