diff --git a/.github/workflows/testing.yml b/.github/workflows/testing.yml
index f406515e..b0a281c5 100644
--- a/.github/workflows/testing.yml
+++ b/.github/workflows/testing.yml
@@ -23,7 +23,7 @@ jobs:
         shell: bash -el {0}
     strategy:
       matrix:
-        python-version: ["3.9", "3.10"]
+        python-version: ["3.9", "3.10", "3.12"]
 
     steps:
       - uses: actions/checkout@v3
diff --git a/environment-ci.yml b/environment-ci.yml
index 4bc4c43f..a16cf6f7 100644
--- a/environment-ci.yml
+++ b/environment-ci.yml
@@ -3,3 +3,4 @@ channels:
   - conda-forge
 dependencies:
   - esmpy
+  - numpy<2.0.0
diff --git a/pyproject.toml b/pyproject.toml
index e427db43..dacad296 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -12,7 +12,7 @@ dependencies = [
   "dask[array]",
   "dask[distributed]",
   "netCDF4",
-  "numpy >= 1.17.0",
+  "numpy >= 1.17.0, < 2.0.0",
   "scipy >= 1.2.0",
   "xarray",
   "xesmf >= 0.8.4",