diff --git a/modules/OSWin32.core b/modules/OSWin32.core
new file mode 100644
index 0000000..56393cf
--- /dev/null
+++ b/modules/OSWin32.core
@@ -0,0 +1,65 @@
+#import "KERNEL32.core"
+#import "Base.core"
+
+PAGE_SIZE :: 4096
+Memory :: struct
+  commit : SizeU
+  reserve: SizeU
+  data   : *U8
+
+ProcessHeap: HANDLE
+Allocate :: (size: U64): *void
+  if ProcessHeap == 0
+    ProcessHeap = GetProcessHeap()
+  return HeapAlloc(ProcessHeap, 0, size)
+
+Reserve :: (size: SizeU): Memory
+  result := Memory{reserve=AlignUp(size, PAGE_SIZE)}
+  result.data = VirtualAlloc(
+    flProtect        = PAGE_READWRITE,
+    dwSize           = result.reserve,
+    flAllocationType = MEM_RESERVE,
+    lpAddress        = 0)->*U8
+  return result
+
+Commit :: (m: *Memory, size: SizeU): Bool
+  commit_size := AlignUp(size, PAGE_SIZE)
+  total_commit := m.commit + commit_size
+  clamped_commit := ClampTopSizeU(total_commit, m.reserve)
+  adjusted_commit := clamped_commit - m.commit
+  if adjusted_commit != 0
+    result := VirtualAlloc(
+      lpAddress        = (m.data + m.commit)->*void,
+      dwSize           = adjusted_commit,
+      flAllocationType = MEM_COMMIT,
+      flProtect        = PAGE_READWRITE,
+    )
+    Assert(result != 0)
+    m.commit += adjusted_commit
+    return true
+  return false
+
+Release :: (m: *Memory)
+  result := VirtualFree(m.data->*void, 0, MEM_RELEASE)
+  if result != 0
+    m.data    = 0
+    m.commit  = 0
+    m.reserve = 0
+
+WriteConsole :: (string: String16)
+  handle := GetStdHandle(STD_OUTPUT_HANDLE)
+  WriteConsoleW(handle, string.str->*void, string.len->DWORD, 0, 0)
+
+PerformanceFrequency: F64
+PerformanceFrequency_S64: S64
+Time :: (): F64
+  query: LARGE_INTEGER
+  if PerformanceFrequency_S64 == 0
+    err := QueryPerformanceFrequency(&PerformanceFrequency_S64)
+    Assert(err != 0)
+    PerformanceFrequency = PerformanceFrequency_S64->F64
+
+  err := QueryPerformanceCounter(&query)
+  Assert(err != 0)
+  result := query->F64 / PerformanceFrequency
+  return result