diff --git a/Source/DrangPlatform/Include/drang/fs.h b/Source/DrangPlatform/Include/drang/fs.h
index b212903..89d2b2b 100644
--- a/Source/DrangPlatform/Include/drang/fs.h
+++ b/Source/DrangPlatform/Include/drang/fs.h
@@ -2,6 +2,7 @@
 #include "platform.h"
 #include <stdbool.h>
 #include <stdint.h>
+#include <stddef.h>
 
 DRANG_BEGIN_DECLS
 
@@ -59,8 +60,7 @@ typedef uint32_t drang_fs_permissions_t;
 /**
  * @brief File system timestamp type.
  *
- * Represents file timestamps as 64-bit values. The specific format
- * and epoch may be platform-dependent.
+ * Represents 64-bits of time in seconds since the Unix epoch (1970-01-01 00:00:00 UTC).
  */
 typedef uint64_t drang_fs_time_t;