diff --git a/test_libs/pyspec/eth2spec/fuzzing/decoder.py b/test_libs/pyspec/eth2spec/fuzzing/decoder.py
index ccca17385..e3b4de318 100644
--- a/test_libs/pyspec/eth2spec/fuzzing/decoder.py
+++ b/test_libs/pyspec/eth2spec/fuzzing/decoder.py
@@ -19,13 +19,13 @@ def translate_typ(typ) -> ssz.BaseSedes:
         return ssz.Vector(translate_typ(typ.elem_type), typ.length)
     elif issubclass(typ, spec_ssz.List):
         # TODO: Make py-ssz List support the new fixed length list
-        return ssz.List(translate_typ(typ.elem_type))
+        return ssz.List(translate_typ(typ.elem_type), typ.length)
     elif issubclass(typ, spec_ssz.Bitlist):
         # TODO: Once Bitlist implemented in py-ssz, use appropriate type
-        return ssz.List(translate_typ(typ.elem_type))
+        return ssz.Bitlist(typ.length)
     elif issubclass(typ, spec_ssz.Bitvector):
         # TODO: Once Bitvector implemented in py-ssz, use appropriate type
-        return ssz.Vector(translate_typ(typ.elem_type), typ.length)
+        return ssz.Bitvector(typ.length)
     elif issubclass(typ, spec_ssz.boolean):
         return ssz.boolean
     elif issubclass(typ, spec_ssz.uint):
diff --git a/test_libs/pyspec/eth2spec/fuzzing/test_decoder.py b/test_libs/pyspec/eth2spec/fuzzing/test_decoder.py
index ea1f1d47f..e68133bd6 100644
--- a/test_libs/pyspec/eth2spec/fuzzing/test_decoder.py
+++ b/test_libs/pyspec/eth2spec/fuzzing/test_decoder.py
@@ -9,9 +9,7 @@ def test_decoder():
     rng = Random(123)
 
     # check these types only, Block covers a lot of operation types already.
-    # TODO: Once has Bitlists and Bitvectors, add back
-    #       spec.BeaconState and spec.BeaconBlock
-    for typ in [spec.IndexedAttestation, spec.AttestationDataAndCustodyBit]:
+    for typ in [spec.BeaconState, spec.BeaconBlock]:
         # create a random pyspec value
         original = random_value.get_random_ssz_object(rng, typ, 100, 10,
                                                       mode=random_value.RandomizationMode.mode_random,
diff --git a/test_libs/pyspec/requirements.txt b/test_libs/pyspec/requirements.txt
index 713b4331a..5aeea4cab 100644
--- a/test_libs/pyspec/requirements.txt
+++ b/test_libs/pyspec/requirements.txt
@@ -3,4 +3,4 @@ eth-typing>=2.1.0,<3.0.0
 pycryptodome==3.7.3
 py_ecc==1.7.1
 dataclasses==0.6
-ssz==0.1.0a10
+ssz==0.1.0a11
diff --git a/test_libs/pyspec/setup.py b/test_libs/pyspec/setup.py
index 07e538e80..9bdbdb2e9 100644
--- a/test_libs/pyspec/setup.py
+++ b/test_libs/pyspec/setup.py
@@ -9,7 +9,7 @@ setup(
         "eth-typing>=2.1.0,<3.0.0",
         "pycryptodome==3.7.3",
         "py_ecc==1.7.1",
-        "ssz==0.1.0a10",
+        "ssz==0.1.0a11",
         "dataclasses==0.6",
     ]
 )