diff --git a/core/.gitignore b/core/.gitignore
new file mode 100644
index 0000000000000000000000000000000000000000..0ee3d5607cf56e6cc305ded0d94bc95d51abb9ab
--- /dev/null
+++ b/core/.gitignore
@@ -0,0 +1,7 @@
+# Ignore node_modules folder created when installing core's JavaScript
+# dependencies.
+node_modules
+
+# Ignore overrides of core's phpcs.xml.dist and phpunit.xml.dist.
+phpcs.xml
+phpunit.xml
diff --git a/example.gitignore b/example.gitignore
index 4fde30a8a1f582679d4da8ceaef5798ed4eb9f65..d1e35ac003194adfbce3ae11e6afe71dea48a070 100644
--- a/example.gitignore
+++ b/example.gitignore
@@ -14,10 +14,6 @@
 # Core's dependencies are managed with Composer.
 vendor
 
-# Ignore node_modules folder created when installing core's JavaScript
-# dependencies.
-core/node_modules
-
 # Ignore configuration files that may contain sensitive information.
 sites/*/settings*.php
 sites/*/services*.yml
@@ -41,7 +37,3 @@ sites/simpletest
 
 # Ignore SimpleTest multi-site environment.
 # simpletest
-
-# Ignore core phpcs.xml and phpunit.xml.
-core/phpcs.xml
-core/phpunit.xml