diff --git a/sphinx/builders/__init__.py b/sphinx/builders/__init__.py
index 1947c27b0b6..ac034b9cde7 100644
--- a/sphinx/builders/__init__.py
+++ b/sphinx/builders/__init__.py
@@ -297,6 +297,7 @@ def build_update(self) -> None:
                        summary=__('targets for %d source files that are out of date') %
                        len(to_build))
 
+    @final
     def build(
         self,
         docnames: Iterable[str] | None,
@@ -305,6 +306,21 @@ def build(
     ) -> None:
         """Main build method, usually called by a specific ``build_*`` method.
 
+        First updates the environment, and then calls
+        :meth:`!write`.
+        """
+        self._build(docnames, summary, method)
+
+    def _build(
+        self,
+        docnames: Iterable[str] | None,
+        summary: str | None = None,
+        method: Literal['all', 'specific', 'update'] = 'update',
+    ) -> None:
+        """Internal build method.
+        
+        This should not be overriden by consumers of this library.
+
         First updates the environment, and then calls
         :meth:`!write`.
         """
diff --git a/sphinx/builders/gettext.py b/sphinx/builders/gettext.py
index 076d6971543..1cbe0aec54d 100644
--- a/sphinx/builders/gettext.py
+++ b/sphinx/builders/gettext.py
@@ -257,14 +257,14 @@ def _extract_from_template(self) -> None:
                 msg = f'{template}: {exc!r}'
                 raise ThemeError(msg) from exc
 
-    def build(
+    def _build(
         self,
         docnames: Iterable[str] | None,
         summary: str | None = None,
         method: Literal['all', 'specific', 'update'] = 'update',
     ) -> None:
         self._extract_from_template()
-        super().build(docnames, summary, method)
+        super()._build(docnames, summary, method)
 
     def finish(self) -> None:
         super().finish()