diff --git a/setup.cfg b/setup.cfg
index a19ac36..89f57a9 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,5 +1,5 @@
 [egg_info]
-tag_build = dev
+tag_build = b1
 
 [wheel]
 universal = 1
diff --git a/tools/build.sh b/tools/build.sh
index 7aa8859..a5dcbeb 100755
--- a/tools/build.sh
+++ b/tools/build.sh
@@ -77,7 +77,7 @@ pyenv uninstall -f $VENV_NAME
 #----------------------------------------------------------------------
 
 _echo_task "Building source distribution"
-_open_env 2.7.11
+_open_env 2.7.12
 
 python setup.py sdist -d $DIST_DIR
 
@@ -88,7 +88,7 @@ _close_env
 #----------------------------------------------------------------------
 
 _echo_task "Building universal wheel"
-_open_env 2.7.11
+_open_env 2.7.12
 
 python setup.py bdist_wheel -d $DIST_DIR