diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 0000000..fcadb2c
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1 @@
+* text eol=lf
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index d455494..0e7217a 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -16,7 +16,7 @@ jobs:
         strategy:
             fail-fast: false
             matrix:
-                os: [ubuntu-latest, macos-latest]
+                os: [ubuntu-latest, macos-latest, windows-latest]
 
         defaults:
             run:
@@ -41,7 +41,5 @@ jobs:
             - run: make run-cases
               if: runner.os != 'Windows'
 
-            - run: make run-cases
+            - run: make run-cases-windows
               if: runner.os == 'Windows'
-              env:
-                  CFLAGS: "-g -std=gnu11 -Wall -Wextra -Werror -Wno-shadow -lm"
diff --git a/Makefile b/Makefile
index 9a1a624..444a219 100644
--- a/Makefile
+++ b/Makefile
@@ -34,8 +34,14 @@ dist:
 	@echo "Created dist/solod.tar.gz"
 
 run-cases:
+	@make run-cases-by pattern="testdata/lang/*/ testdata/std/*/"
+
+run-cases-windows:
+	@make run-cases-by CFLAGS="-g -std=gnu11 -Wall -Wextra -Werror -Wno-shadow -lm" pattern="testdata/lang/*/"
+
+run-cases-by:
 	@failed=0; \
-	for dir in testdata/lang/*/ testdata/std/*/; do \
+	for dir in $(pattern); do \
 		name=$${dir#testdata/}; \
 		name=$${name%/}; \
 		if make run-case name=$$name > /tmp/so_test_out.txt 2>&1; then \
diff --git a/README.md b/README.md
index cf3488e..8e43b2f 100644
--- a/README.md
+++ b/README.md
@@ -174,7 +174,7 @@ So generates C11 code that relies on several GCC/Clang extensions:
 
 You can use GCC, Clang, or `zig cc` to compile the transpiled C code. MSVC is not supported.
 
-Supported operating systems: Linux, macOS, and Windows (partial support).
+Supported operating systems: Linux, macOS, and Windows (core language only).
 
 ## Design decisions
 
diff --git a/internal/compiler/builtin/builtin.h b/internal/compiler/builtin/builtin.h
index f79c341..e603b1f 100644
--- a/internal/compiler/builtin/builtin.h
+++ b/internal/compiler/builtin/builtin.h
@@ -1,6 +1,11 @@
 #pragma once
 
+#ifdef _WIN32
+#include <malloc.h>
+#else
 #include <alloca.h>
+#endif
+
 #include <inttypes.h>
 #include <stdalign.h>
 #include <stdbool.h>