diff --git a/.circleci/config.yml b/.circleci/config.yml
index f3870d922..afa5b82d9 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -35,32 +35,32 @@ commands:
     description: "Restore the cache with pyspec keys"
     steps:
       - restore_cached_venv:
-          venv_name: v5-pyspec
+          venv_name: v6-pyspec
           reqs_checksum: cache-{{ checksum "test_libs/pyspec/requirements.txt" }}-{{ checksum "test_libs/pyspec/requirements-testing.txt" }}
   save_pyspec_cached_venv:
     description: Save a venv into a cache with pyspec keys"
     steps:
       - save_cached_venv:
-          venv_name: v5-pyspec
+          venv_name: v6-pyspec
           reqs_checksum: cache-{{ checksum "test_libs/pyspec/requirements.txt" }}-{{ checksum "test_libs/pyspec/requirements-testing.txt" }}
           venv_path: ./test_libs/pyspec/venv
   restore_deposit_contract_cached_venv:
     description: "Restore the cache with deposit_contract keys"
     steps:
       - restore_cached_venv:
-          venv_name: v8-deposit-contract
+          venv_name: v9-deposit-contract
           reqs_checksum: cache-{{ checksum "test_libs/pyspec/requirements.txt" }}-{{ checksum "deposit_contract/requirements-testing.txt" }}
   save_deposit_contract_cached_venv:
     description: Save a venv into a cache with deposit_contract keys"
     steps:
       - save_cached_venv:
-          venv_name: v8-deposit-contract
+          venv_name: v9-deposit-contract
           reqs_checksum: cache-{{ checksum "test_libs/pyspec/requirements.txt" }}-{{ checksum "deposit_contract/requirements-testing.txt" }}
           venv_path: ./deposit_contract/venv
 jobs:
   checkout_specs:
     docker:
-      - image: circleci/python:3.6
+      - image: circleci/python:3.8
     working_directory: ~/specs-repo
     steps:
       # Restore git repo at point close to target branch/revision, to speed up checkout
@@ -80,7 +80,7 @@ jobs:
             - ~/specs-repo
   install_pyspec_test:
     docker:
-      - image: circleci/python:3.6
+      - image: circleci/python:3.8
     working_directory: ~/specs-repo
     steps:
       - restore_cache:
@@ -92,7 +92,7 @@ jobs:
       - save_pyspec_cached_venv
   test:
     docker:
-      - image: circleci/python:3.6
+      - image: circleci/python:3.8
     working_directory: ~/specs-repo
     steps:
       - restore_cache:
@@ -114,7 +114,7 @@ jobs:
           command: sudo npm install -g doctoc && make check_toc
   codespell:
     docker:
-      - image: circleci/python:3.6
+      - image: circleci/python:3.8
     working_directory: ~/specs-repo
     steps:
       - checkout
@@ -123,7 +123,7 @@ jobs:
           command: pip install codespell --user &&  make codespell
   lint:
     docker:
-      - image: circleci/python:3.6
+      - image: circleci/python:3.8
     working_directory: ~/specs-repo
     steps:
       - restore_cache:
@@ -134,7 +134,7 @@ jobs:
           command: make lint
   install_deposit_contract_test:
     docker:
-      - image: circleci/python:3.6
+      - image: circleci/python:3.8
     working_directory: ~/specs-repo
     steps:
       - restore_cache:
@@ -146,7 +146,7 @@ jobs:
       - save_deposit_contract_cached_venv
   deposit_contract:
     docker:
-      - image: circleci/python:3.6
+      - image: circleci/python:3.8
     working_directory: ~/specs-repo
     steps:
       - restore_cache:
diff --git a/test_libs/pyspec/setup.py b/test_libs/pyspec/setup.py
index 5be0db7f8..204187efc 100644
--- a/test_libs/pyspec/setup.py
+++ b/test_libs/pyspec/setup.py
@@ -3,6 +3,7 @@ from setuptools import setup, find_packages
 setup(
     name='pyspec',
     packages=find_packages(),
+    python_requires=">=3.8, <4",
     tests_require=["pytest"],
     install_requires=[
         "eth-utils>=1.3.0,<2",