diff --git a/include/uring/syscall.hpp b/include/uring/syscall.hpp
index 0f5e5e5..7ec5015 100644
--- a/include/uring/syscall.hpp
+++ b/include/uring/syscall.hpp
@@ -10,6 +10,42 @@
 #include <sys/syscall.h>
 #include <unistd.h>
 
+#ifdef __alpha__
+/*
+ * alpha and mips are the exceptions, all other architectures have
+ * common numbers for new system calls.
+ */
+#ifndef __NR_io_uring_setup
+#define __NR_io_uring_setup 535
+#endif
+#ifndef __NR_io_uring_enter
+#define __NR_io_uring_enter 536
+#endif
+#ifndef __NR_io_uring_register
+#define __NR_io_uring_register 537
+#endif
+#elif defined __mips__
+#ifndef __NR_io_uring_setup
+#define __NR_io_uring_setup (__NR_Linux + 425)
+#endif
+#ifndef __NR_io_uring_enter
+#define __NR_io_uring_enter (__NR_Linux + 426)
+#endif
+#ifndef __NR_io_uring_register
+#define __NR_io_uring_register (__NR_Linux + 427)
+#endif
+#else /* !__alpha__ and !__mips__ */
+#ifndef __NR_io_uring_setup
+#define __NR_io_uring_setup 425
+#endif
+#ifndef __NR_io_uring_enter
+#define __NR_io_uring_enter 426
+#endif
+#ifndef __NR_io_uring_register
+#define __NR_io_uring_register 427
+#endif
+#endif
+
 /*
  * Don't put this below the #include "arch/$arch/syscall.h", that
  * file may need it.