diff --git a/spacy/symbols.pxd b/spacy/symbols.pxd
index 0b713cb21..e981de6ae 100644
--- a/spacy/symbols.pxd
+++ b/spacy/symbols.pxd
@@ -1,4 +1,4 @@
-cpdef enum symbol_t:
+cdef enum symbol_t:
     NIL
     IS_ALPHA
     IS_ASCII
diff --git a/spacy/symbols.pyx b/spacy/symbols.pyx
index 9f4009579..dd0e38cad 100644
--- a/spacy/symbols.pyx
+++ b/spacy/symbols.pyx
@@ -1,4 +1,6 @@
 # coding: utf8
+#cython: optimize.unpack_method_calls=False
+
 from __future__ import unicode_literals
 
 IDS = {
@@ -458,4 +460,11 @@ IDS = {
     "xcomp": xcomp
 }
 
-NAMES = [it[0] for it in sorted(IDS.items(), key=lambda it: it[1])]
+def sort_nums(x):
+    return x[1]
+
+NAMES = [it[0] for it in sorted(IDS.items(), key=sort_nums)]
+# Unfortunate hack here, to work around problem with long cpdef enum
+# (which is generating an enormous amount of C++ in Cython 0.24+)
+# We keep the enum cdef, and just make sure the names are available to Python
+locals().update(IDS)