chore: Upgrade to latest Rust toolchain

README.md

@@ -12,7 +12,7 @@
 This repository contains a set of crates that help you build robust highly scalable services in Rust.
 
 - [Crates](#crates)
-- [About This Repo](#about-this-repo)
+- [About this Repo](#about-this-repo)
     - [Adding New Crates](#adding-new-crates)
     - [Publishing Crates](#publishing-crates)
     - [Documenting Crates](#documenting-crates)
@@ -35,7 +35,7 @@ These are the primary crates built out of this repo:
 - [`thread_aware`](./crates/thread_aware/README.md) - Facilities to support thread-isolated state.
 - [`tick`](./crates/tick/README.md) - Provides primitives to interact with and manipulate machine time.
 
-## About This Repo
+## About this Repo
 
 The following sections explain the overall engineering process we use
 in this repo.

constants.env

@@ -8,9 +8,9 @@
 # used for testing, ensures the MSRV promise is kept; must match Cargo.toml [workspace.package].rust-version
 RUST_MSRV=1.88
 # used for static analysis & mutation testing; must match rust-toolchain.toml
-RUST_LATEST=1.92
+RUST_LATEST=1.93
 # used for coverage and extended analysis; update on a regular basis
-RUST_NIGHTLY=nightly-2026-01-17
+RUST_NIGHTLY=nightly-2026-01-21
 # used for external type exposure checks; update alongside updates to cargo-check-external-types
 RUST_NIGHTLY_EXTERNAL_TYPES=nightly-2025-10-18
 

rust-toolchain.toml

@@ -3,7 +3,7 @@
 
 [toolchain]
 # This needs to match RUST_LATEST in constants.env.
-channel = "1.92"
+channel = "1.93"
 
 # Additional targets to install for all builds (in both cloud and local builds).
 # The toolchain will always come with support for the host platform.