diff --git a/deps/labjack/ljacklm/build.zig b/deps/labjack/ljacklm/build.zig
index 78ec2c9..7cb124f 100644
--- a/deps/labjack/ljacklm/build.zig
+++ b/deps/labjack/ljacklm/build.zig
@@ -17,6 +17,10 @@ pub fn build(b: *std.Build) !void {
         .link_libc = true,
     });
 
+    if (target.result.os.tag == .windows) {
+        libljacklm.defineCMacro("LJACKLM_USE_WINDOWS_MUTEX_SHIM", "1");
+    }
+
     libljacklm.addCSourceFile(.{ .file = b.path("libljacklm/ljacklm.c") });
     libljacklm.installHeader(b.path("libljacklm/ljacklm.h"), "ljacklm.h");
 
diff --git a/deps/labjack/ljacklm/libljacklm/ljacklm.c b/deps/labjack/ljacklm/libljacklm/ljacklm.c
index 0febd8c..eddb20c 100644
--- a/deps/labjack/ljacklm/libljacklm/ljacklm.c
+++ b/deps/labjack/ljacklm/libljacklm/ljacklm.c
@@ -23,7 +23,14 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
-#include <pthread.h>
+
+#if defined(LJACKLM_USE_WINDOWS_MUTEX_SHIM)
+	#include <windows.h>
+	#include "windows_mutex_shim.h"
+#else
+	#include <pthread.h>
+#endif // LJACKLM_USE_WINDOWS_MUTEX_SHIM
+
 #include "labjackusb.h"
 
 
@@ -286,7 +293,9 @@ long GetU12Information( HANDLE hDevice,
 					    long *fcddMaxSize,
 					    long *hvcMaxSize);
 
+#if !defined(LJACKLM_USE_WINDOWS_MUTEX_SHIM)
 unsigned long GetTickCount( void);
+#endif
 
 
 __attribute__((constructor))
@@ -7266,6 +7275,7 @@ long GetU12Information( HANDLE hDevice,
 }
 
 
+#if !defined(LJACKLM_USE_WINDOWS_MUTEX_SHIM)
 //======================================================================
 //GetTickCount:	Implementation of GetTickCount() for Unix.  Returns the
 //				current time, expressed as millisconds since the Epoch 
@@ -7276,3 +7286,4 @@ unsigned long GetTickCount( void)
 	gettimeofday(&tv, NULL);
 	return (tv.tv_sec * 1000) + (tv.tv_usec / 1000);
 }
+#endif
diff --git a/deps/labjack/ljacklm/libljacklm/windows_mutex_shim.h b/deps/labjack/ljacklm/libljacklm/windows_mutex_shim.h
new file mode 100644
index 0000000..6ba645a
--- /dev/null
+++ b/deps/labjack/ljacklm/libljacklm/windows_mutex_shim.h
@@ -0,0 +1,28 @@
+#ifndef LJACKLM_WIN_MUTEX
+#define LJACKLM_WIN_MUTEX
+
+typedef CRITICAL_SECTION pthread_mutex_t;
+
+static inline int pthread_mutex_init(pthread_mutex_t *mutex, void *attr) {
+    InitializeCriticalSection(mutex);
+    return 0;
+}
+
+static inline void pthread_mutex_lock(pthread_mutex_t *mutex) {
+    EnterCriticalSection(mutex);
+}
+
+static inline int pthread_mutex_unlock(pthread_mutex_t *mutex) {
+    LeaveCriticalSection(mutex);
+    return 0;
+}
+
+static inline int pthread_mutex_trylock(pthread_mutex_t *mutex) {
+    return TryEnterCriticalSection(mutex) == 0;
+}
+
+static inline void pthread_mutex_destroy(pthread_mutex_t *mutex) {
+    DeleteCriticalSection(mutex);
+}
+
+#endif // LJACKLM_WIN_MUTEX