diff --git a/devtools/conda-envs/conda.yaml b/devtools/conda-envs/conda.yaml
index ee269f69d..4ac8f1e5c 100644
--- a/devtools/conda-envs/conda.yaml
+++ b/devtools/conda-envs/conda.yaml
@@ -6,4 +6,6 @@ dependencies:
   - openff-toolkit-examples
     # Tests
   - pytest
+  - pytest-xdist
+  - pytest-randomly
   - pytest-rerunfailures
diff --git a/devtools/conda-envs/conda_oe.yaml b/devtools/conda-envs/conda_oe.yaml
index cef46c327..375ada423 100644
--- a/devtools/conda-envs/conda_oe.yaml
+++ b/devtools/conda-envs/conda_oe.yaml
@@ -8,4 +8,6 @@ dependencies:
     # Tests
   - openeye-toolkits
   - pytest
+  - pytest-xdist
+  - pytest-randomly
   - pytest-rerunfailures