diff --git a/lang/rust-bootstrap/Portfile b/lang/rust-bootstrap/Portfile
index 24bdb002cf9fb..50d22f48b7ad6 100644
--- a/lang/rust-bootstrap/Portfile
+++ b/lang/rust-bootstrap/Portfile
@@ -26,7 +26,7 @@ license                     {MIT Apache-2} BSD zlib NCSA Permissive
 # we only need this port to be built once, so include `any`
 # however, we need it to build on a machine capable of building a 32-bit binary
 # see https://trac.macports.org/ticket/69198
-platforms                   {darwin any >= 16 <= 17}
+platforms                   {darwin any >= 16 < 18}
 maintainers                 {mcalhoun @MarcusCalhoun-Lopez} \
                             openmaintainer