diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 9e7ec1ae..69e1c633 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -196,21 +196,22 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-latest, windows-latest]
+        os: [ubuntu-latest, windows-latest, macos-latest]
+    env:
+      MSRV: 1.66.0
     steps:
       - uses: actions/checkout@v4
       - name: Install Rust
         run: |
-          rustup toolchain install 1.63.0 --no-self-update --profile minimal
+          rustup toolchain install $MSRV --no-self-update --profile minimal
           rustup toolchain install nightly --no-self-update --profile minimal
-          rustup default 1.63.0
+          rustup default $MSRV
         shell: bash
       - name: Create Cargo.lock with minimal version
         run: cargo +nightly update -Zminimal-versions
-      - name: Cache downloaded crates since 1.63 is really slow in fetching
-        uses: Swatinem/rust-cache@v2
-      - run: cargo check --lib -p cc --locked
-      - run: cargo check --lib -p cc --locked --all-features
+      - uses: Swatinem/rust-cache@v2
+      - run: env -u CARGO_REGISTRIES_CRATES_IO_PROTOCOL cargo check --lib -p cc --locked
+      - run: env -u CARGO_REGISTRIES_CRATES_IO_PROTOCOL cargo check --lib -p cc --locked --all-features
 
   clippy:
     name: Clippy
diff --git a/Cargo.toml b/Cargo.toml
index c2419475..310d82b4 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -17,7 +17,7 @@ categories = ["development-tools::build-utils"]
 # The binary target is only used by tests.
 exclude = ["/.github", "tests", "src/bin"]
 edition = "2018"
-rust-version = "1.63"
+rust-version = "1.66"
 
 [dependencies]
 jobserver = { version = "0.1.30", default-features = false, optional = true }