diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 39b7cef..0c593ab 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -12,15 +12,15 @@ permissions:
 
 jobs:
   install:
-    name: Rust ${{matrix.rust}} on ${{matrix.os == 'ubuntu' && 'Linux' || matrix.os == 'macos' && 'macOS' || matrix.os == 'windows' && 'Windows' || '???'}}
-    runs-on: ${{matrix.os}}-latest
+    name: Rust ${{matrix.rust}} on ${{matrix.os}}
+    runs-on: ${{matrix.os}}
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu, macos, windows]
+        os: [ubuntu-latest, macos-latest, windows-latest, windows-11-arm, ubuntu-22.04-arm]
         rust: [nightly, beta, stable, 1.62.0, stable 18 months ago, stable minus 8 releases]
         include:
-          - os: ubuntu
+          - os: ubuntu-latest
             rust: 1.0.0
     timeout-minutes: 45
     steps:
diff --git a/action.yml b/action.yml
index 5281d42..64cdda2 100644
--- a/action.yml
+++ b/action.yml
@@ -8,7 +8,8 @@ branding:
 inputs:
   toolchain:
     description: Rust toolchain specification -- see https://rust-lang.github.io/rustup/concepts/toolchains.html#toolchain-specification
-    required: true
+    required: false
+    default: nightly
   targets:
     description: Comma-separated list of target triples to install for this toolchain
     required: false
@@ -63,18 +64,28 @@ runs:
 
     - run: |
         : set $CARGO_HOME
-        echo CARGO_HOME=${CARGO_HOME:-${{runner.os == 'Windows' && '$USERPROFILE' || '$HOME'}}/.cargo} >> $GITHUB_ENV
+        echo CARGO_HOME=${CARGO_HOME:-"${{runner.os == 'Windows' && '$USERPROFILE\.cargo' || '$HOME/.cargo'}}"} >> $GITHUB_ENV
       shell: bash
 
     - run: |
         : install rustup if needed
         if ! command -v rustup &>/dev/null; then
-          curl --proto '=https' --tlsv1.2 --retry 10 --retry-connrefused --location --silent --show-error --fail "https://sh.rustup.rs" | sh -s -- --default-toolchain none -y
+          curl --proto '=https' --tlsv1.2 --retry 10 --retry-connrefused --location --silent --show-error --fail https://sh.rustup.rs | sh -s -- --default-toolchain none -y
           echo "$CARGO_HOME/bin" >> $GITHUB_PATH
         fi
       if: runner.os != 'Windows'
       shell: bash
 
+    - run: |
+        : install rustup if needed on windows
+        if ! command -v rustup &>/dev/null; then
+          curl --proto '=https' --tlsv1.2 --retry 10 --retry-connrefused --location --silent --show-error --fail https://win.rustup.rs/${{runner.arch == 'ARM64' && 'aarch64' || 'x86_64'}} --output '${{runner.temp}}\rustup-init.exe'
+          '${{runner.temp}}\rustup-init.exe' --default-toolchain none --no-modify-path -y
+          echo "$CARGO_HOME\bin" >> $GITHUB_PATH
+        fi
+      if: runner.os == 'Windows'
+      shell: bash
+
     - name: rustup toolchain install ${{steps.parse.outputs.toolchain}}
       run: rustup toolchain install ${{steps.parse.outputs.toolchain}}${{steps.flags.outputs.targets}}${{steps.flags.outputs.components}} --profile minimal${{steps.flags.outputs.downgrade}} --no-self-update
       shell: bash