Index: head/devel/py-srsly/Makefile
===================================================================
--- head/devel/py-srsly/Makefile	(revision 541134)
+++ head/devel/py-srsly/Makefile	(revision 541135)
@@ -1,23 +1,23 @@
 # $FreeBSD$
 
 PORTNAME=	srsly
 DISTVERSION=	2.1.0
 CATEGORIES=	devel python
 MASTER_SITES=	CHEESESHOP
 PKGNAMEPREFIX=	${PYTHON_PKGNAMEPREFIX}
 
 MAINTAINER=	jwb@FreeBSD.org
 COMMENT=	Modern high-performance serialization utilities for Python
 
 LICENSE=	MIT
 LICENSE_FILE=	${WRKSRC}/LICENSE
 
 BUILD_DEPENDS=	${PYTHON_PKGNAMEPREFIX}wheel>=0:devel/py-wheel@${PY_FLAVOR}
 
-USES=		python
+USES=		python:3.6+
 USE_PYTHON=	autoplist cython distutils
 
 post-install:
 	@${STRIP_CMD} ${STAGEDIR}${PYTHON_SITELIBDIR}/srsly/*/*.so
 
 .include <bsd.port.mk>