diff --git a/tox.ini b/tox.ini
index b3b516d0..6c90339e 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-isolated_build = True
+isolated_build = true
 skipsdist = true
 usedevelop = true
 envlist = py{38,39,310,311,312}-{all,core}, docs