diff --git a/doc/PKGBUILD.5.asciidoc b/doc/PKGBUILD.5.asciidoc
index 83a61458..6336a5cd 100644
--- a/doc/PKGBUILD.5.asciidoc
+++ b/doc/PKGBUILD.5.asciidoc
@@ -359,7 +359,11 @@ function.
 
 *build() Function*::
 	The optional `build()` function is use to compile and/or adjust the source
-	files in preparation to be installed by the `package()` function.
+	files in preparation to be installed by the `package()` function. All
+	commands specific to the package creation (but not source code
+	preparation), before the final installation of files into the packaging
+	root, should be performed here. The `build()` function is permitted to run
+	multiple times if `makepkg --noextract` is used.
 
 *check() Function*::
 	An optional `check()` function can be specified in which a package's