diff --git a/test_libs/pyspec/eth2spec/debug/decode.py b/test_libs/pyspec/eth2spec/debug/decode.py
index e9aa8bc2b..261692bed 100644
--- a/test_libs/pyspec/eth2spec/debug/decode.py
+++ b/test_libs/pyspec/eth2spec/debug/decode.py
@@ -1,28 +1,35 @@
-from eth2spec.utils.minimal_ssz import hash_tree_root
+from eth2spec.utils.ssz.ssz_impl import hash_tree_root
+from eth2spec.utils.ssz.ssz_typing import *
 
 
-def decode(json, typ):
-    if isinstance(typ, str) and typ[:4] == 'uint':
-        return json
-    elif typ == 'bool':
-        assert json in (True, False)
-        return json
-    elif isinstance(typ, list):
-        return [decode(element, typ[0]) for element in json]
-    elif isinstance(typ, str) and typ[:4] == 'byte':
-        return bytes.fromhex(json[2:])
-    elif hasattr(typ, 'fields'):
+def decode(data, typ):
+    if is_uint(typ):
+        return data
+    elif is_bool_type(typ):
+        assert data in (True, False)
+        return data
+    elif issubclass(typ, list):
+        elem_typ = read_list_elem_typ(typ)
+        return [decode(element, elem_typ) for element in data]
+    elif issubclass(typ, Vector):
+        elem_typ = read_vector_elem_typ(typ)
+        return Vector(decode(element, elem_typ) for element in data)
+    elif issubclass(typ, bytes):
+        return bytes.fromhex(data[2:])
+    elif issubclass(typ, BytesN):
+        return BytesN(bytes.fromhex(data[2:]))
+    elif is_container_typ(typ):
         temp = {}
-        for field, subtype in typ.fields.items():
-            temp[field] = decode(json[field], subtype)
-            if field + "_hash_tree_root" in json:
-                assert(json[field + "_hash_tree_root"][2:] ==
+        for field, subtype in typ.get_fields():
+            temp[field] = decode(data[field], subtype)
+            if field + "_hash_tree_root" in data:
+                assert(data[field + "_hash_tree_root"][2:] ==
                        hash_tree_root(temp[field], subtype).hex())
         ret = typ(**temp)
-        if "hash_tree_root" in json:
-            assert(json["hash_tree_root"][2:] ==
+        if "hash_tree_root" in data:
+            assert(data["hash_tree_root"][2:] ==
                    hash_tree_root(ret, typ).hex())
         return ret
     else:
-        print(json, typ)
+        print(data, typ)
         raise Exception("Type not recognized")
diff --git a/test_libs/pyspec/eth2spec/debug/encode.py b/test_libs/pyspec/eth2spec/debug/encode.py
index b38e5fe98..3c0658c8f 100644
--- a/test_libs/pyspec/eth2spec/debug/encode.py
+++ b/test_libs/pyspec/eth2spec/debug/encode.py
@@ -1,24 +1,27 @@
-from eth2spec.utils.minimal_ssz import hash_tree_root
+from eth2spec.utils.ssz.ssz_impl import hash_tree_root
+from eth2spec.utils.ssz.ssz_typing import *
 
 
 def encode(value, typ, include_hash_tree_roots=False):
-    if isinstance(typ, str) and typ[:4] == 'uint':
-        if typ[4:] == '128' or typ[4:] == '256':
+    if is_uint(typ):
+        if issubclass(typ, uint) and typ.byte_len > 8:
             return str(value)
         return value
-    elif typ == 'bool':
+    elif is_bool_type(typ):
         assert value in (True, False)
         return value
-    elif isinstance(typ, list):
-        return [encode(element, typ[0], include_hash_tree_roots) for element in value]
-    elif isinstance(typ, str) and typ[:4] == 'byte':
+    elif issubclass(typ, list) or issubclass(typ, Vector):
+        elem_typ = read_elem_typ(typ)
+        return [encode(element, elem_typ, include_hash_tree_roots) for element in value]
+    elif issubclass(typ, bytes):
         return '0x' + value.hex()
-    elif hasattr(typ, 'fields'):
+    elif is_container_typ(typ):
         ret = {}
-        for field, subtype in typ.fields.items():
-            ret[field] = encode(getattr(value, field), subtype, include_hash_tree_roots)
+        for field, subtype in typ.get_fields():
+            field_value = getattr(value, field)
+            ret[field] = encode(field_value, subtype, include_hash_tree_roots)
             if include_hash_tree_roots:
-                ret[field + "_hash_tree_root"] = '0x' + hash_tree_root(getattr(value, field), subtype).hex()
+                ret[field + "_hash_tree_root"] = '0x' + hash_tree_root(field_value, subtype).hex()
         if include_hash_tree_roots:
             ret["hash_tree_root"] = '0x' + hash_tree_root(value, typ).hex()
         return ret