diff --git a/plugins/python-build/test/build.bats b/plugins/python-build/test/build.bats
index 466aebcf..f0e3a1b8 100644
--- a/plugins/python-build/test/build.bats
+++ b/plugins/python-build/test/build.bats
@@ -67,6 +67,10 @@ assert_build_log() {
   stub_make_install
   stub_make_install
 
+  # yyuu/pyenv#257
+  stub uname '-s : echo Linux'
+  stub uname '-s : echo Linux'
+
   install_fixture definitions/needs-yaml
   assert_success
 
@@ -93,6 +97,10 @@ OUT
   stub_make_install
   stub patch ' : echo patch "$@" | sed -E "s/\.[[:alnum:]]+$/.XXX/" >> build.log'
 
+  # yyuu/pyenv#257
+  stub uname '-s : echo Linux'
+  stub uname '-s : echo Linux'
+
   TMPDIR="$TMP" install_fixture --patch definitions/needs-yaml <<<""
   assert_success
 
@@ -121,6 +129,10 @@ OUT
   stub_make_install
   stub patch ' : echo patch "$@" | sed -E "s/\.[[:alnum:]]+$/.XXX/" >> build.log'
 
+  # yyuu/pyenv#257
+  stub uname '-s : echo Linux'
+  stub uname '-s : echo Linux'
+
   TMPDIR="$TMP" install_fixture --patch definitions/needs-yaml <<<"diff --git a/script.py"
   assert_success
 
@@ -149,6 +161,10 @@ OUT
   stub brew "--prefix libyaml : echo '$brew_libdir'" false
   stub_make_install
 
+  # yyuu/pyenv#257
+  stub uname '-s : echo Linux'
+  stub uname '-s : echo Linux'
+
   install_fixture definitions/needs-yaml
   assert_success
 
@@ -172,6 +188,10 @@ OUT
   stub brew "--prefix readline : echo '$readline_libdir'"
   stub_make_install
 
+  # yyuu/pyenv#257
+  stub uname '-s : echo Linux'
+  stub uname '-s : echo Linux'
+
   run_inline_definition <<DEF
 install_package "Python-3.2.1" "http://python.org/ftp/python/3.2.1/Python-3.2.1.tar.gz"
 DEF
@@ -199,6 +219,10 @@ OUT
   stub brew
   stub_make_install
 
+  # yyuu/pyenv#257
+  stub uname '-s : echo Linux'
+  stub uname '-s : echo Linux'
+
   export PYTHON_CONFIGURE_OPTS="CPPFLAGS=-I$readline_libdir/include LDFLAGS=-L$readline_libdir/lib"
   run_inline_definition <<DEF
 install_package "Python-3.2.1" "http://python.org/ftp/python/3.2.1/Python-3.2.1.tar.gz"
@@ -317,6 +341,10 @@ OUT
 
   stub_make_install
 
+  # yyuu/pyenv#257
+  stub uname '-s : echo Linux'
+  stub uname '-s : echo Linux'
+
   export PYTHON_MAKE_INSTALL_OPTS="DOGE=\"such wow\""
   run_inline_definition <<DEF
 install_package "Python-3.2.1" "http://python.org/ftp/python/3.2.1/Python-3.2.1.tar.gz"
@@ -412,6 +440,10 @@ CONF
   stub apply 'echo apply "$@" >> build.log'
   stub_make_install
 
+  # yyuu/pyenv#257
+  stub uname '-s : echo Linux'
+  stub uname '-s : echo Linux'
+
   export PYTHON_CONFIGURE="${TMP}/custom-configure"
   run_inline_definition <<DEF
 install_package "Python-3.2.1" "http://python.org/ftp/python/3.2.1/Python-3.2.1.tar.gz"
diff --git a/plugins/python-build/test/pyenv_ext.bats b/plugins/python-build/test/pyenv_ext.bats
index bcda77c7..823662c0 100644
--- a/plugins/python-build/test/pyenv_ext.bats
+++ b/plugins/python-build/test/pyenv_ext.bats
@@ -101,6 +101,10 @@ resolve_link() {
 
   echo | install_patch definitions/vanilla-python "Python-3.2.1/empty.patch"
 
+  # yyuu/pyenv#257
+  stub uname '-s : echo Linux'
+  stub uname '-s : echo Linux'
+
   TMPDIR="$TMP" install_tmp_fixture definitions/vanilla-python < /dev/null
   assert_success
 
@@ -127,6 +131,10 @@ OUT
   echo "bar" | install_patch definitions/vanilla-python "Python-3.2.1/bar.patch"
   echo "baz" | install_patch definitions/vanilla-python "Python-3.2.1/baz.patch"
 
+  # yyuu/pyenv#257
+  stub uname '-s : echo Linux'
+  stub uname '-s : echo Linux'
+
   TMPDIR="$TMP" install_tmp_fixture definitions/vanilla-python < /dev/null
   assert_success
 
@@ -152,6 +160,10 @@ OUT
     " : echo \"$MAKE \$@\" >> build.log" \
     " : echo \"$MAKE \$@\" >> build.log && cat build.log >> '$INSTALL_ROOT/build.log'"
 
+  # yyuu/pyenv#257
+  stub uname '-s : echo Linux'
+  stub uname '-s : echo Linux'
+
   PYTHON_MAKE_INSTALL_TARGET="altinstall" TMPDIR="$TMP" install_tmp_fixture definitions/vanilla-python < /dev/null
   assert_success