diff --git a/openGJK_cython.c b/openGJK_cython.c
deleted file mode 100644
index 06f2230..0000000
--- a/openGJK_cython.c
+++ /dev/null
@@ -1 +0,0 @@
-#error Do not use this file, it is the result of a failed Cython compilation.
diff --git a/openGJK_cython.pxd b/openGJK_cython.pxd
new file mode 100644
index 0000000..724ab00
--- /dev/null
+++ b/openGJK_cython.pxd
@@ -0,0 +1,14 @@
+# Declare C function and data types
+cdef extern from "openGJK.h":
+	struct bd:
+		int numpoints
+		double s[3]
+		double ** coord
+
+	struct simplex:
+		int nvrtx
+		double vrtx[4][3]
+		int wids[4]
+		double lambdas[4]
+
+	double gjk(bd bd1, bd bd2, simplex *s)