diff --git a/sys/include/ubixos/uthread.h b/sys/include/ubixos/uthread.h
new file mode 100644
index 0000000..cf5577f
--- /dev/null
+++ b/sys/include/ubixos/uthread.h
@@ -0,0 +1,29 @@
+#ifndef _UBIXOS_UTHREAD_H
+#define _UBIXOS_UTHREAD_H
+
+#include <sys/cdefs.h>
+#include <sys/types.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct uthread {
+  struct uthread *uthread_pointer;
+  size_t uthread_size;
+  unsigned long uthread_flags;
+  void *tls_master_mmap;
+  size_t tls_master_size;
+  size_t tls_master_align;
+  void *tls_mmap;
+  size_t stack_size;
+  void *arg_mmap;
+  size_t arg_size;
+  size_t __uthread_reserved[4];
+};
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif