Update #15281 Release Notes for 0.15 (no_std)

release-content/0.15/release-notes/15281_Add_core_and_alloc_over_std_Lints.md

@@ -1,4 +1,50 @@
 <!-- Add `core` and `alloc` over `std` Lints -->
 <!-- https://github.com/bevyengine/bevy/pull/15281 -->
 
-<!-- TODO -->
+Bevy relies heavily on Rust's [standard library](https://doc.rust-lang.org/std/), making it
+challenging to use on embedded, niche platforms, and even certain consoles. But what if that
+_wasn't_ the case?
+
+We've undertaken a new initiative to challenge the reliance on the standard
+library, with the eventual goal of providing a [`no_std`](https://docs.rust-embedded.org/book/intro/no-std.html)
+compatible subset of Bevy which could be used on a much wider range of platforms.
+
+The first very simple step is to enable a new set of lints:
+
+* [`std_instead_of_core`](https://rust-lang.github.io/rust-clippy/master/index.html#std_instead_of_core)
+* [`std_instead_of_alloc`](https://rust-lang.github.io/rust-clippy/master/index.html#std_instead_of_alloc)
+* [`alloc_instead_of_core`](https://rust-lang.github.io/rust-clippy/master/index.html#alloc_instead_of_core)
+
+For those unfamiliar with `no_std` Rust, the standard library, `std`, gets a lot of its functionality
+from two smaller crates, [`core`](https://doc.rust-lang.org/core/) and [`alloc`](https://doc.rust-lang.org/alloc/).
+The `core` crate is available on every Rust target with very few exceptions, providing the
+fundamental infrastructure that the Rust language relies on, such as iterators, `Result`, and many more.
+Complementing that the `alloc` crate provides access to allocation-related functionality, such as
+`Vec`, `Box`, and `String`.
+
+Rust's support for platforms follows a [three tiered policy](https://doc.rust-lang.org/rustc/platform-support.html),
+where tier 1 is guaranteed to work and will always provide the `std` crate, and tiers 2 and 3 _may_
+have the `std` crate, but often do not.
+The reason for this is some platforms simply don't support the features the `std` crate requires,
+such as a filesystem, networking, or threading.
+
+But why should Bevy care about these platforms? When a new platform is added to Rust,
+it is often lacking tier 1 support.
+Even modern consoles such as the Nintendo Switch, PlayStation 5, or Xbox Series don't have tier 1
+support due to non-disclosure agreements and platform specifics.
+Adding `no_std` support to Bevy will make it easier for commercial teams developing for these
+platforms to get started and stay up to date.
+
+Beyond the commercially-relevant modern consoles, there is a vibrant community of embedded and retro
+enthusiasts developing for platforms that may never support the standard library.
+Crates such as [`agb`](https://crates.io/crates/agb) and [`psx`](https://crates.io/crates/psx) provide
+support for developing games on the GameBoy Advance and PlayStation One respectively.
+With `no_std` support in Bevy, users may be able to leverage the wider Rust ecosystem to run their
+software on these platforms.
+
+We're still a while away from true `no_std` support in Bevy, but the first few changes have already
+been accepted, with many more lined up for the next release in 0.16.
+
+If this work sounds interesting, check out the
+[`no_std` tracking issue](https://github.com/bevyengine/bevy/issues/15460) on GitHub, where you can
+find a list of pull requests, and even prototypes of Bevy running in `no_std` environments.