diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index d5fd59e1..8ea0db9c 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -11,12 +11,12 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        python-version: [3.6, 3.7]
+        python-version: ['3.8', '3.9', '3.10', '3.11']
         os: [ubuntu-20.04, macos-latest]
     steps:
     - uses: actions/checkout@v1
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v1
+      uses: actions/setup-python@v2
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install package
@@ -28,12 +28,12 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        python-version: [3.6, 3.7]
+        python-version: ['3.8', '3.9', '3.10', '3.11']
         os: [ubuntu-20.04, macos-latest]
     steps:
     - uses: actions/checkout@v1
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v1
+      uses: actions/setup-python@v2
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install package and dependencies
@@ -45,12 +45,12 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        python-version: [3.6, 3.7]
+        python-version: ['3.8', '3.9', '3.10', '3.11']
         os: [ubuntu-20.04, macos-latest]
     steps:
     - uses: actions/checkout@v1
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v1
+      uses: actions/setup-python@v2
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install package and dependencies
diff --git a/cardea/data_loader/data_loader.py b/cardea/data_loader/data_loader.py
index e2ba959a..21665bfb 100644
--- a/cardea/data_loader/data_loader.py
+++ b/cardea/data_loader/data_loader.py
@@ -2,7 +2,6 @@
 import sys
 
 import networkx as nx
-import numpy as np
 import pandas as pd
 from numpy import nan
 
@@ -126,9 +125,8 @@ def check_for_missing_values(self, entity_set, target_entity, column_name):
         """
         if self.check_column_existence(entity_set, target_entity, column_name):
 
-            nat = np.datetime64('NaT')
+            # nat = np.datetime64('NaT')
             missings = [
-                nat,
                 nan,
                 'null',
                 'nan',
diff --git a/cardea/modeling/modeler.py b/cardea/modeling/modeler.py
index 68d48959..01a00900 100644
--- a/cardea/modeling/modeler.py
+++ b/cardea/modeling/modeler.py
@@ -4,7 +4,7 @@
 import numpy as np
 import pandas as pd
 import sklearn
-from btb.session import BTBSession
+from baytune.session import BTBSession
 from mlblocks import MLPipeline
 from sklearn.model_selection import KFold, train_test_split
 
@@ -32,8 +32,21 @@ class Modeler:
         'Confusion Matrix': sklearn.metrics.confusion_matrix
     }
 
+    @staticmethod
+    def _load_pipeline(pipeline):
+        mlpipeline = MLPipeline(pipeline)
+        hyperparameters = pipeline.get_hyperparameters()
+        for primitive, values in hyperparameters.items():
+            for hyperparam, value in values.items():
+                if isinstance(value, list):
+                    hyperparameters[primitive][hyperparam] = tuple(value)
+
+        mlpipeline.set_hyperparameters(hyperparameters)
+
+        return mlpipeline
+
     def __init__(self, pipeline, problem_type):
-        self._pipeline = MLPipeline(pipeline)
+        self._pipeline = self._load_pipeline(pipeline)
         self._problem_type = problem_type
 
     @staticmethod
@@ -97,7 +110,7 @@ def pipeline(self):
             MLPipeline:
                 The pipeline in the modeler.
         """
-        return MLPipeline(self._pipeline)
+        return self._load_pipeline(self._pipeline)
 
     def k_fold_validation(self, hyperparameters, X, y, scoring=None):
         """Score the pipeline through k-fold validation with the given scoring function.
@@ -116,7 +129,7 @@ def k_fold_validation(self, hyperparameters, X, y, scoring=None):
             np.float64:
                 The average score in the k-fold validation.
         """
-        model_instance = MLPipeline(self._pipeline)
+        model_instance = self._load_pipeline(self._pipeline)
         X = pd.DataFrame(X)
         y = pd.Series(y)
 
diff --git a/setup.py b/setup.py
index 9a5a5620..c065818b 100644
--- a/setup.py
+++ b/setup.py
@@ -14,7 +14,7 @@
     'mlprimitives>=0.3.6.dev0,<0.5',
     'baytune>=0.5,<0.6',
     'pyCLI==2.0.3',
-    # 'scikit-learn>=0.21,<0.22',
+    'scikit-learn>=1.2,<2',
     # 'featuretools>=0.20.0,<0.25',
 ]
 
@@ -68,8 +68,10 @@
         'License :: OSI Approved :: MIT License',
         'Natural Language :: English',
         'Programming Language :: Python :: 3',
-        'Programming Language :: Python :: 3.6',
-        'Programming Language :: Python :: 3.7',
+        'Programming Language :: Python :: 3.8',
+        'Programming Language :: Python :: 3.9',
+        'Programming Language :: Python :: 3.10',
+        'Programming Language :: Python :: 3.11',
     ],
     description="Cardea",
     entry_points={
@@ -90,7 +92,7 @@
     long_description_content_type='text/markdown',
     name='cardea',
     packages=find_packages(include=['cardea', 'cardea.*']),
-    python_requires='>=3.4',
+    python_requires='>=3.8,<3.12',
     setup_requires=setup_requires,
     test_suite='tests',
     tests_require=tests_require,
diff --git a/tox.ini b/tox.ini
index 6895ed00..becff058 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,11 +1,13 @@
 [tox]
-envlist = py37, py36, lint, docs
+envlist = py3{8,9,10,11}, lint, docs
 
 
 [travis]
 python =
-    3.6: py36, lint, docs
-    3.7: py37
+    3.8: py38, lint, docs
+    3.9: py39
+    3.10: py310
+    3.11: py311
 
 
 [testenv]