diff --git a/.nextcloudignore b/.nextcloudignore
new file mode 100644
index 0000000000000..47253d2e8ddb3
--- /dev/null
+++ b/.nextcloudignore
@@ -0,0 +1,29 @@
+# SPDX-FileCopyrightText: 2026 Nextcloud GmbH and Nextcloud contributors
+# SPDX-License-Identifier: AGPL-3.0-only
+# Files removed at build time
+
+# Global exclude
+.editorconfig
+.git
+.git-blame-ignore-revs
+.gitattributes
+.github
+.gitignore
+.gitmodules
+.idea
+.l10nignore
+.nextcloudignore
+.noopenapi
+.tx
+cypress
+tests
+
+# Server specific
+/.devcontainer
+/__mocks__
+/__tests__
+/autotest*.sh
+/build
+/config/config.php
+/contribute
+/data
diff --git a/build/files-checker.php b/build/files-checker.php
index 4f8d471078b1a..178083fe6baa9 100644
--- a/build/files-checker.php
+++ b/build/files-checker.php
@@ -22,6 +22,7 @@
 	'.idea',
 	'.jshintrc',
 	'.mailmap',
+	'.nextcloudignore',
 	'.npmignore',
 	'.php-cs-fixer.dist.php',
 	'.pre-commit-config.yaml',