# Rust Enabling the next iteration of the borrow checker on nightly

- Product: Rust (https://whatsnew.fyi/product/rust)
- Vendor: Rust Foundation
- Date: 2026-08-04
- Original notes: https://blog.rust-lang.org/2026/08/04/enabling-polonius-alpha-on-nightly/
- Permalink: https://whatsnew.fyi/product/rust/releases/2026-08-04-enabling-the-next-iteration-of-the-borrow-checker

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TL;DR We are enabling the next iteration of the borrow checker (coined Polonius Alpha) on nightly in preparation for stabilization in the next few months. Whaaaaaat? Yes! You heard it right! The next…

- **added** — Enable Polonius Alpha, the next iteration of the borrow checker, on nightly in preparation for stabilization