diff --git a/README.md b/README.md
index ff80bc4..5735ad1 100644
--- a/README.md
+++ b/README.md
@@ -11,9 +11,9 @@ purpose of building PHP composer packages.  It provides several key features:
 * Access to the build location will be in the volume located at `/code`.  This
   directory will be the default working directory.
 * PHP limited access using `open_basedir`.  By default, access is only granted
-  to `/code` and `$COMPOSER_HOME`.  For general builds this should likely be
-  sufficient, but should you need to override the settings you can do so by
-  updating `/etc/php/conf.d/basedir.ini`.
+  to `/code`, `/tmp`, and `$COMPOSER_HOME`.  For general builds this should
+  likely be sufficient, but should you need to override the settings you can do
+  so by updating `/etc/php/conf.d/basedir.ini`.
 * Composer bin directories are automatically included in `PATH`.  Both a
   relative `vendor/bin` directory, and the global `$COMPOSER_HOME/vendor/bin`
   directory are included in the `PATH`.
diff --git a/basedir.ini b/basedir.ini
index 411844d..f5136ae 100644
--- a/basedir.ini
+++ b/basedir.ini
@@ -1,2 +1,2 @@
 [PHP]
-open_basedir = /code:/home/build/.composer
+open_basedir = /code:/home/build/.composer:/tmp