diff --git a/libc/include/sys/param.h b/libc/include/sys/param.h
index 79ae067..1c991ae 100644
--- a/libc/include/sys/param.h
+++ b/libc/include/sys/param.h
@@ -41,8 +41,11 @@
 /** The unit of `st_blocks` in `struct stat`. */
 #define DEV_BSIZE 512
 
-/** A historical name for PATH_MAX. */
-#define MAXPATHLEN  PATH_MAX
+/** A historical name for PATH_MAX. Use PATH_MAX in new code. */
+#define MAXPATHLEN PATH_MAX
+
+/** A historical name for NGROUPS_MAX. Use NGROUPS_MAX in new code. */
+#define NGROUPS NGROUPS_MAX
 
 #define MAXSYMLINKS 8