diff --git a/plugins/python-build/share/python-build/ironpython-2.7.6.3 b/plugins/python-build/share/python-build/ironpython-2.7.6.3
index 94bca05e..fce1f312 100644
--- a/plugins/python-build/share/python-build/ironpython-2.7.6.3
+++ b/plugins/python-build/share/python-build/ironpython-2.7.6.3
@@ -1,2 +1,2 @@
-install_zip "IronPython-2.7.6.3" "https://github.com/IronLanguages/main/releases/download/ipy-2.7.6.3/IronPython-2.7.6.3.zip" ironpython
+install_zip "IronPython-2.7.6.3" "https://github.com/IronLanguages/main/releases/download/ipy-2.7.6.3/IronPython-2.7.6.3.zip#dfd00598f4752104f90c248c1662eafbebf7ead24e17531d852ffc32a5a8075b" ironpython
 # FIXME: have not confirmed to install setuptools into IronPython yet
diff --git a/plugins/python-build/share/python-build/stackless-2.7.9 b/plugins/python-build/share/python-build/stackless-2.7.9
index 53b69da0..806e4235 100644
--- a/plugins/python-build/share/python-build/stackless-2.7.9
+++ b/plugins/python-build/share/python-build/stackless-2.7.9
@@ -1,4 +1,4 @@
 #require_gcc
 install_package "openssl-1.0.2g" "https://www.openssl.org/source/openssl-1.0.2g.tar.gz#b784b1b3907ce39abf4098702dade6365522a253ad1552e267a9a0e89594aa33" mac_openssl --if has_broken_mac_openssl
 install_package "readline-6.3" "https://ftpmirror.gnu.org/readline/readline-6.3.tar.gz#56ba6071b9462f980c5a72ab0023893b65ba6debb4eeb475d7a563dc65cafd43" standard --if has_broken_mac_readline
-install_package "stackless-dev-stackless-43302de87df4" "https://bitbucket.org/stackless-dev/stackless/get/v2.7.9-slp.tar.bz2" ldflags_dirs standard verify_py27 ensurepip
+install_package "stackless-dev-stackless-43302de87df4" "https://bitbucket.org/stackless-dev/stackless/get/v2.7.9-slp.tar.bz2#83857fb269a59cca51c68aef84295892f86ce775700dbe9a3f7fe8322f7dd6ff" ldflags_dirs standard verify_py27 ensurepip
diff --git a/plugins/python-build/share/python-build/stackless-3.4.2 b/plugins/python-build/share/python-build/stackless-3.4.2
new file mode 100644
index 00000000..ef489833
--- /dev/null
+++ b/plugins/python-build/share/python-build/stackless-3.4.2
@@ -0,0 +1,4 @@
+#require_gcc
+install_package "openssl-1.0.2g" "https://www.openssl.org/source/openssl-1.0.2g.tar.gz#b784b1b3907ce39abf4098702dade6365522a253ad1552e267a9a0e89594aa33" mac_openssl --if has_broken_mac_openssl
+install_package "readline-6.3" "https://ftpmirror.gnu.org/readline/readline-6.3.tar.gz#56ba6071b9462f980c5a72ab0023893b65ba6debb4eeb475d7a563dc65cafd43" standard --if has_broken_mac_readline
+install_package "stackless-dev-stackless-587417070fe4" "https://bitbucket.org/stackless-dev/stackless/get/v3.4.2-slp.tar.bz2#c3dbdde536fa6bf366fdbc3e957596487608ba11009758ce599357512eb74103" ldflags_dirs standard verify_py34 ensurepip