diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index d8470f0..1ba1e82 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -78,8 +78,8 @@ jobs:
         set -euxo pipefail
 
         # Install the appropriate version of Rust.
-        rustup toolchain install 1.77.0 # [ref:rust_1.77.0]
-        rustup default 1.77.0 # [ref:rust_1.77.0]
+        rustup toolchain install 1.78.0 # [ref:rust_1.78.0]
+        rustup default 1.78.0 # [ref:rust_1.78.0]
 
         # Add the targets.
         rustup target add x86_64-pc-windows-msvc
@@ -118,8 +118,8 @@ jobs:
         set -euxo pipefail
 
         # Install the appropriate version of Rust.
-        rustup toolchain install 1.77.0 # [ref:rust_1.77.0]
-        rustup default 1.77.0 # [ref:rust_1.77.0]
+        rustup toolchain install 1.78.0 # [ref:rust_1.78.0]
+        rustup default 1.78.0 # [ref:rust_1.78.0]
 
         # Add the targets.
         rustup target add x86_64-apple-darwin
@@ -191,8 +191,8 @@ jobs:
         set -euxo pipefail
 
         # Install the appropriate version of Rust.
-        rustup toolchain install 1.77.0 # [ref:rust_1.77.0]
-        rustup default 1.77.0 # [ref:rust_1.77.0]
+        rustup toolchain install 1.78.0 # [ref:rust_1.78.0]
+        rustup default 1.78.0 # [ref:rust_1.78.0]
 
         # Fetch the program version.
         VERSION="$(cargo pkgid | cut -d# -f2 | cut -d: -f2)"
diff --git a/Cargo.toml b/Cargo.toml
index 3733f90..2477eb2 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -11,9 +11,9 @@ repository = "https://github.com/stepchowfun/tagref"
 readme = "README.md"
 
 [lints]
-clippy.all = "deny"
+clippy.all = { level = "deny", priority = -1 }
 clippy.default_numeric_fallback = "deny"
-clippy.pedantic = "deny"
+clippy.pedantic = { level = "deny", priority = -1 }
 rust.warnings = "deny"
 
 [dependencies]
diff --git a/toast.yml b/toast.yml
index 2c04100..245baa5 100644
--- a/toast.yml
+++ b/toast.yml
@@ -17,11 +17,11 @@ command_prefix: |
   cargo-offline () { cargo --frozen --offline "$@"; }
 
   # Use this wrapper for formatting code or checking that code is formatted. We use a nightly Rust
-  # version for the `trailing_comma` formatting option [tag:rust_fmt_nightly_2024-03-23]. The
+  # version for the `trailing_comma` formatting option [tag:rust_fmt_nightly_2024-05-04]. The
   # nightly version was chosen as the latest available release with all components present
   # according to this page:
   #   https://rust-lang.github.io/rustup-components-history/x86_64-unknown-linux-gnu.html
-  cargo-fmt () { cargo +nightly-2024-03-23 --frozen --offline fmt --all -- "$@"; }
+  cargo-fmt () { cargo +nightly-2024-05-04 --frozen --offline fmt --all -- "$@"; }
 tasks:
   install_packages:
     description: Install system packages.
@@ -68,18 +68,18 @@ tasks:
       - install_packages
       - create_user
     command: |
-      # Install stable Rust [tag:rust_1.77.0].
+      # Install stable Rust [tag:rust_1.78.0].
       curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- \
         -y \
-        --default-toolchain 1.77.0 \
+        --default-toolchain 1.78.0 \
         --profile minimal \
         --component clippy
 
       # Add Rust tools to `$PATH`.
       . "$HOME/.cargo/env"
 
-      # Install nightly Rust [ref:rust_fmt_nightly_2024-03-23].
-      rustup toolchain install nightly-2024-03-23 --profile minimal --component rustfmt
+      # Install nightly Rust [ref:rust_fmt_nightly_2024-05-04].
+      rustup toolchain install nightly-2024-05-04 --profile minimal --component rustfmt
 
   install_tools:
     description: Install the tools needed to build and validate the program.