diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 6c2c191..8817d27 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ["3.9", "3.10", "3.11"]
+        python-version: ["3.10", "3.11"]
 
     name: Set up Python ${{ matrix.python-version }}
     steps:
diff --git a/.readthedocs.yaml b/.readthedocs.yaml
index 04ad88b..6e5cef0 100644
--- a/.readthedocs.yaml
+++ b/.readthedocs.yaml
@@ -5,7 +5,7 @@ version: 2
 build:
   os: ubuntu-20.04
   tools:
-    python: "3.9"
+    python: "3.10"
 
 python:
    install:
diff --git a/pymc_bart/pgbart.py b/pymc_bart/pgbart.py
index b4cf23b..e7b0762 100644
--- a/pymc_bart/pgbart.py
+++ b/pymc_bart/pgbart.py
@@ -23,7 +23,7 @@
 from pymc.step_methods.compound import Competence
 from pytensor import config
 from pytensor import function as pytensor_function
-from pytensor.tensor.var import Variable
+from pytensor.tensor.variable import Variable
 
 from pymc_bart.bart import BARTRV
 from pymc_bart.split_rules import ContinuousSplitRule
diff --git a/pymc_bart/utils.py b/pymc_bart/utils.py
index 39e0620..ef61cd8 100644
--- a/pymc_bart/utils.py
+++ b/pymc_bart/utils.py
@@ -8,7 +8,7 @@
 import numpy as np
 import numpy.typing as npt
 import pytensor.tensor as pt
-from pytensor.tensor.var import Variable
+from pytensor.tensor.variable import Variable
 from scipy.interpolate import griddata
 from scipy.signal import savgol_filter
 from scipy.stats import norm, pearsonr
diff --git a/requirements.txt b/requirements.txt
index 447fe26..027c2b5 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,5 @@
-pymc>=5.0.0
-arviz
+pymc==5.13.1
+arviz==0.18.0
 numba
 matplotlib
 numpy