1 files changed, 1 insertions, 0 deletions
diff --git a/tox.ini b/tox.ini
index a5ce930f..3eb408cc 100644
--- a/tox.ini
+++ b/tox.ini
@@ -18,6 +18,7 @@ install_command = {[helpers]pip} install {opts} {packages}
 list_dependencies_command = {[helpers]pip} freeze --all
 setenv =
 	COVERAGE_FILE={toxworkdir}/.coverage.{envname}
+	PIP_USE_PEP517=1
 # TODO: The passed environment variables came from copying other tox.ini files
 # These should probably be individually annotated to explain what needs them.
 passenv=APPDATA HOMEDRIVE HOMEPATH windir APPVEYOR APPVEYOR_* CI CODECOV_* TRAVIS TRAVIS_* NETWORK_REQUIRED