diff --git a/tools/build-lxml.sh b/tools/build-lxml.sh
index 61f922f..581a83e 100755
--- a/tools/build-lxml.sh
+++ b/tools/build-lxml.sh
@@ -104,7 +104,7 @@ XSLT_CONFIG=$PREFIX/bin/xslt-config
 #pushd src
 #find . -name *.pyx -exec $KIVYIOSROOT/tools/cythonize.py {} \;
 #popd
-find . -name *.pyx -exec cython {} \;
+find . -name *.pyx -exec $CYTHON {} \;
 
 try $HOSTPYTHON setup.py build_ext 
 try $HOSTPYTHON setup.py install -O2 --root iosbuild
diff --git a/tools/cythonize.py b/tools/cythonize.py
index 4e79136..466d169 100755
--- a/tools/cythonize.py
+++ b/tools/cythonize.py
@@ -1,8 +1,20 @@
 #!/usr/bin/env python
 
+import os
 import sys
 import subprocess
 
+# resolve cython executable
+cython = None
+
+def resolve_cython():
+    global cython
+    for executable in ('cython', 'cython-2.7'):
+        for path in os.environ['PATH'].split(':'):
+            if executable in os.listdir(path):
+                cython = os.path.join(path, executable)
+                return
+
 def do(fn):
     print 'cythonize:', fn
     parts = fn.split('/')
@@ -13,7 +25,7 @@ def do(fn):
     package = '_'.join(parts[:-1])
 
     # cythonize
-    subprocess.Popen(['cython', fn]).communicate()
+    subprocess.Popen([cython, fn]).communicate()
 
     if not package:
         print 'no need to rewrite', fn
@@ -43,5 +55,6 @@ def do(fn):
 
 if __name__ == '__main__':
     print '-- cythonize', sys.argv
+    resolve_cython()
     for fn in sys.argv[1:]:
         do(fn)
diff --git a/tools/environment.sh b/tools/environment.sh
index 97561e4..31848eb 100755
--- a/tools/environment.sh
+++ b/tools/environment.sh
@@ -44,6 +44,19 @@ export PKG_CONFIG_PATH="$BUILDROOT/pkgconfig:$PKG_CONFIG_PATH"
 
 # some tools
 export CCACHE=$(which ccache)
+for fn in cython-2.7 cython; do
+	export CYTHON=$(which $fn)
+	if [ "X$CYTHON" != "X" ]; then
+		echo "Cython found at $CYTHON"
+		break
+	fi
+done
+if [ "X$CYTHON" == "X" ]; then
+	print "Cython is not installed, aborting."
+	exit 1
+fi
+
+
 
 # flags for arm compilation
 export ARM_CC="$CCACHE $DEVROOT/usr/bin/arm-apple-darwin10-llvm-gcc-4.2"