diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 0ba03923..bc80f96e 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -9,7 +9,7 @@ jobs:
   test:
     strategy:
       matrix:
-        os: [ubuntu-latest, ubuntu-24.04-arm, macos-latest, windows-latest]
+        os: [ubuntu-latest, ubuntu-24.04-arm, macos-latest, windows-latest, windows-11-arm]
         go: ['1.25.x', '1.26.x']
     name: Test with Go ${{ matrix.go }} on ${{ matrix.os }}
     runs-on: ${{ matrix.os }}
@@ -31,8 +31,8 @@ jobs:
         with:
           go-version: ${{ matrix.go }}
 
-      - name: Set up the prerequisites
-        if: runner.os == 'Windows'
+      - name: Set up Msys2
+        if: runner.os == 'Windows' && runner.arch != 'ARM64'
         uses: msys2/setup-msys2@v2
 
       - name: go vet
@@ -127,6 +127,10 @@ jobs:
         if: runner.os == 'Windows'
         run: |
           env CGO_ENABLED=0 GOARCH=386 go test -shuffle=on -v -count=10 ./...
+
+      - name: go test (Windows 386, Cgo)
+        if: runner.os == 'Windows' && runner.arch != 'ARM64'
+        run: |
           env CGO_ENABLED=1 GOARCH=386 go test -shuffle=on -v -count=10 ./...
 
       - name: go test (Linux 386)
@@ -180,6 +184,7 @@ jobs:
           env CGO_ENABLED=0 go test -race -shuffle=on -v -count=10 ./...
 
       - name: go test race (Cgo)
+        if: ${{ !(runner.os == 'Windows' && runner.arch == 'ARM64') }}
         run: |
           env CGO_ENABLED=1 go test -race -shuffle=on -v -count=10 ./...
 
diff --git a/callback_test.go b/callback_test.go
index b298081b..ec795990 100644
--- a/callback_test.go
+++ b/callback_test.go
@@ -22,7 +22,7 @@ func TestCallGoFromSharedLib(t *testing.T) {
 	libFileName := filepath.Join(t.TempDir(), "libcbtest.so")
 	t.Logf("Build %v", libFileName)
 
-	if err := buildSharedLib("CC", libFileName, filepath.Join("testdata", "libcbtest", "callback_test.c")); err != nil {
+	if err := buildSharedLib(t, "CC", libFileName, filepath.Join("testdata", "libcbtest", "callback_test.c")); err != nil {
 		t.Fatal(err)
 	}
 	defer os.Remove(libFileName)
@@ -186,7 +186,7 @@ func TestCallbackInt32Packing(t *testing.T) {
 	}
 
 	libFileName := filepath.Join(t.TempDir(), "libcbtest_packing.so")
-	if err := buildSharedLib("CC", libFileName, filepath.Join("testdata", "libcbtest", "callback_packing_test.c")); err != nil {
+	if err := buildSharedLib(t, "CC", libFileName, filepath.Join("testdata", "libcbtest", "callback_packing_test.c")); err != nil {
 		t.Fatal(err)
 	}
 	defer os.Remove(libFileName)
@@ -218,7 +218,7 @@ func TestCallbackMixedStackPacking(t *testing.T) {
 	}
 
 	libFileName := filepath.Join(t.TempDir(), "libcbtest_packing.so")
-	if err := buildSharedLib("CC", libFileName, filepath.Join("testdata", "libcbtest", "callback_packing_test.c")); err != nil {
+	if err := buildSharedLib(t, "CC", libFileName, filepath.Join("testdata", "libcbtest", "callback_packing_test.c")); err != nil {
 		t.Fatal(err)
 	}
 	defer os.Remove(libFileName)
@@ -251,7 +251,7 @@ func TestCallbackSmallTypesPacking(t *testing.T) {
 	}
 
 	libFileName := filepath.Join(t.TempDir(), "libcbtest_packing.so")
-	if err := buildSharedLib("CC", libFileName, filepath.Join("testdata", "libcbtest", "callback_packing_test.c")); err != nil {
+	if err := buildSharedLib(t, "CC", libFileName, filepath.Join("testdata", "libcbtest", "callback_packing_test.c")); err != nil {
 		t.Fatal(err)
 	}
 	defer os.Remove(libFileName)
@@ -319,7 +319,7 @@ func TestCallback10Int32Packing(t *testing.T) {
 	}
 
 	libFileName := filepath.Join(t.TempDir(), "libcbtest_packing.so")
-	if err := buildSharedLib("CC", libFileName, filepath.Join("testdata", "libcbtest", "callback_packing_test.c")); err != nil {
+	if err := buildSharedLib(t, "CC", libFileName, filepath.Join("testdata", "libcbtest", "callback_packing_test.c")); err != nil {
 		t.Fatal(err)
 	}
 	defer os.Remove(libFileName)
@@ -350,7 +350,7 @@ func TestCallbackFloat64StackPacking(t *testing.T) {
 	}
 
 	libFileName := filepath.Join(t.TempDir(), "libcbtest_packing.so")
-	if err := buildSharedLib("CC", libFileName, filepath.Join("testdata", "libcbtest", "callback_packing_test.c")); err != nil {
+	if err := buildSharedLib(t, "CC", libFileName, filepath.Join("testdata", "libcbtest", "callback_packing_test.c")); err != nil {
 		t.Fatal(err)
 	}
 	defer os.Remove(libFileName)
@@ -384,7 +384,7 @@ func TestCallbackFloat32StackPacking(t *testing.T) {
 	}
 
 	libFileName := filepath.Join(t.TempDir(), "libcbtest_packing.so")
-	if err := buildSharedLib("CC", libFileName, filepath.Join("testdata", "libcbtest", "callback_packing_test.c")); err != nil {
+	if err := buildSharedLib(t, "CC", libFileName, filepath.Join("testdata", "libcbtest", "callback_packing_test.c")); err != nil {
 		t.Fatal(err)
 	}
 	defer os.Remove(libFileName)
diff --git a/dlfcn_test.go b/dlfcn_test.go
index 7ca5456c..e358b9bd 100644
--- a/dlfcn_test.go
+++ b/dlfcn_test.go
@@ -24,7 +24,7 @@ func TestNestedDlopenCall(t *testing.T) {
 	libFileName := filepath.Join(t.TempDir(), "libdlnested.so")
 	t.Logf("Build %v", libFileName)
 
-	if err := buildSharedLib("CXX", libFileName, filepath.Join("testdata", "libdlnested", "nested_test.cpp")); err != nil {
+	if err := buildSharedLib(t, "CXX", libFileName, filepath.Join("testdata", "libdlnested", "nested_test.cpp")); err != nil {
 		t.Fatal(err)
 	}
 	defer os.Remove(libFileName)
diff --git a/func_test.go b/func_test.go
index 85e80e82..970919bb 100644
--- a/func_test.go
+++ b/func_test.go
@@ -178,13 +178,10 @@ func TestRegisterLibFunc_Bool(t *testing.T) {
 }
 
 func TestABI(t *testing.T) {
-	if runtime.GOOS == "windows" && runtime.GOARCH == "386" {
-		t.Skip("need a 32bit gcc to run this test") // TODO: find 32bit gcc for test
-	}
 	libFileName := filepath.Join(t.TempDir(), "abitest.so")
 	t.Logf("Build %v", libFileName)
 
-	if err := buildSharedLib("CC", libFileName, filepath.Join("testdata", "abitest", "abi_test.c")); err != nil {
+	if err := buildSharedLib(t, "CC", libFileName, filepath.Join("testdata", "abitest", "abi_test.c")); err != nil {
 		t.Fatal(err)
 	}
 
@@ -242,11 +239,8 @@ func TestABI(t *testing.T) {
 }
 
 func TestABI_ArgumentPassing(t *testing.T) {
-	if runtime.GOOS == "windows" && runtime.GOARCH == "386" {
-		t.Skip("need a 32bit gcc to run this test") // TODO: find 32bit gcc for test
-	}
 	libFileName := filepath.Join(t.TempDir(), "abitest.so")
-	if err := buildSharedLib("CC", libFileName, filepath.Join("testdata", "abitest", "abi_test.c")); err != nil {
+	if err := buildSharedLib(t, "CC", libFileName, filepath.Join("testdata", "abitest", "abi_test.c")); err != nil {
 		t.Fatal(err)
 	}
 	lib, err := load.OpenLibrary(libFileName)
@@ -603,7 +597,8 @@ func TestABI_TooManyArguments(t *testing.T) {
 	})
 }
 
-func buildSharedLib(compilerEnv, libFile string, sources ...string) error {
+func buildSharedLib(tb testing.TB, compilerEnv, libFile string, sources ...string) error {
+	tb.Helper()
 	// When PUREGO_TEST_PREBUILT_LIBDIR is set, the shared library has been
 	// cross-compiled ahead of time and placed in that directory under the
 	// base name of libFile. This allows running the tests on a target that
@@ -619,6 +614,18 @@ func buildSharedLib(compilerEnv, libFile string, sources ...string) error {
 		return nil
 	}
 
+	// Compiling the library needs a C toolchain targeting GOARCH. CI has none
+	// for Windows on 386 or arm64, so skip those (the prebuilt path above
+	// avoids the toolchain).
+	if runtime.GOOS == "windows" {
+		switch runtime.GOARCH {
+		case "386":
+			tb.Skip("need a 386 C toolchain to run this test") // TODO: find a 386 C toolchain for test
+		case "arm64":
+			tb.Skip("need an arm64 C toolchain to run this test")
+		}
+	}
+
 	out, err := exec.Command("go", "env", compilerEnv).Output()
 	if err != nil {
 		return fmt.Errorf("go env %s error: %w", compilerEnv, err)
diff --git a/struct_test.go b/struct_test.go
index a9cd6148..14ed0584 100644
--- a/struct_test.go
+++ b/struct_test.go
@@ -24,7 +24,7 @@ func TestRegisterFunc_structArgs(t *testing.T) {
 	libFileName := filepath.Join(t.TempDir(), "structtest.so")
 	t.Logf("Build %v", libFileName)
 
-	if err := buildSharedLib("CC", libFileName, filepath.Join("testdata", "structtest", "struct_test.c")); err != nil {
+	if err := buildSharedLib(t, "CC", libFileName, filepath.Join("testdata", "structtest", "struct_test.c")); err != nil {
 		t.Fatal(err)
 	}
 	defer os.Remove(libFileName)
@@ -859,7 +859,7 @@ func TestRegisterFunc_structReturns(t *testing.T) {
 	libFileName := filepath.Join(t.TempDir(), "structreturntest.so")
 	t.Logf("Build %v", libFileName)
 
-	if err := buildSharedLib("CC", libFileName, filepath.Join("testdata", "structtest", "structreturn_test.c")); err != nil {
+	if err := buildSharedLib(t, "CC", libFileName, filepath.Join("testdata", "structtest", "structreturn_test.c")); err != nil {
 		t.Fatal(err)
 	}
 	defer os.Remove(libFileName)
diff --git a/syscall_bench_test.go b/syscall_bench_test.go
index 86e8a0c7..4f835c12 100644
--- a/syscall_bench_test.go
+++ b/syscall_bench_test.go
@@ -37,7 +37,7 @@ func BenchmarkCallingMethods(b *testing.B) {
 
 	// Build C library for benchmarking
 	libFileName := filepath.Join(b.TempDir(), "libbenchmark.so")
-	if err := buildSharedLib("CC", libFileName, filepath.Join("testdata", "benchmarktest", "benchmark.c")); err != nil {
+	if err := buildSharedLib(b, "CC", libFileName, filepath.Join("testdata", "benchmarktest", "benchmark.c")); err != nil {
 		b.Fatalf("Failed to build C library: %v", err)
 	}
 	b.Cleanup(func() {
diff --git a/syscall_linux_test.go b/syscall_linux_test.go
index 6a331e3a..45ce47e4 100644
--- a/syscall_linux_test.go
+++ b/syscall_linux_test.go
@@ -173,7 +173,7 @@ func compareStatus(filter, expect string) error {
 func TestDlopenThenAllThreadsSyscall(t *testing.T) {
 	// Step 1: Build and load a shared C library that calls back into Go.
 	libFileName := filepath.Join(t.TempDir(), "libcbtest.so")
-	if err := buildSharedLib("CC", libFileName, filepath.Join("testdata", "libcbtest", "callback_test.c")); err != nil {
+	if err := buildSharedLib(t, "CC", libFileName, filepath.Join("testdata", "libcbtest", "callback_test.c")); err != nil {
 		t.Fatal(err)
 	}
 	defer os.Remove(libFileName)