component/pygolang: force to use a fixed cython version until pygolang supports cython3

component/pygolang/buildout.cfg

@@ -10,6 +10,13 @@ parts =
     pygolang
     gpython-interpreter
 
+[cython-for-pygolang]
+recipe  = slapos.recipe.build:download-unpacked
+url = https://github.com/cython/cython/releases/download/0.29.35/Cython-0.29.35.tar.gz#138dba31e20e178b431a2e403154f906
+
+
+[pygolang-env]
+PYTHONPATH=${cython-for-pygolang:location}
 
 # pygolang is installed from git checkout
 [pygolang]
@@ -17,9 +24,9 @@ recipe  = zc.recipe.egg:develop
 setup   = ${pygolang-repository:location}
 egg     = pygolang
 setup-eggs =
-    ${cython:egg}
     setuptools-dso
     gevent
+environment = pygolang-env
 
 [pygolang-repository]
 recipe  = slapos.recipe.build:gitclone