diff --git a/.azure-pipelines/azure-pipelines-base.yml b/.azure-pipelines/azure-pipelines-base.yml
index b7a2ba1ed9..888801a3a7 100644
--- a/.azure-pipelines/azure-pipelines-base.yml
+++ b/.azure-pipelines/azure-pipelines-base.yml
@@ -5,8 +5,6 @@ jobs:
   variables:
     - name: NUMBA_DISABLE_JIT
       value: 1
-    - name: ARVIZ_CI_MACHINE
-      value: 1
   timeoutInMinutes: 360
   strategy:
     matrix:
@@ -82,9 +80,15 @@ jobs:
       python -m pip freeze
     displayName: 'Print packages'
 
+  - script: |
+      ARVIZ_REQUIRE_ALL_DEPS=TRUE python -m pytest arviz/tests/base_tests --cov arviz --cov-report=xml
+    condition: and(succeeded(), eq(variables.OptionalRequirements, true))
+    displayName: 'pytest (require all dependencies)'
+
   - script: |
       python -m pytest arviz/tests/base_tests --cov arviz --cov-report=xml
-    displayName: 'pytest'
+    condition: and(succeeded(), eq(variables.OptionalRequirements, false))
+    displayName: 'pytest (skip if dependency missing)'
 
   - script: |
       ls -ahl
diff --git a/.azure-pipelines/azure-pipelines-external.yml b/.azure-pipelines/azure-pipelines-external.yml
index b255ee8898..138ff80223 100644
--- a/.azure-pipelines/azure-pipelines-external.yml
+++ b/.azure-pipelines/azure-pipelines-external.yml
@@ -5,7 +5,7 @@ jobs:
   variables:
     - name: NUMBA_DISABLE_JIT
       value: 1
-    - name: ARVIZ_CI_MACHINE
+    - name: ARVIZ_REQUIRE_ALL_DEPS
       value: 1
   timeoutInMinutes: 360
   strategy:
diff --git a/arviz/tests/helpers.py b/arviz/tests/helpers.py
index 15dbd95689..3e826b8587 100644
--- a/arviz/tests/helpers.py
+++ b/arviz/tests/helpers.py
@@ -620,11 +620,6 @@ def test_precompile_models(eight_schools_params, draws, chains):
     load_cached_models(eight_schools_params, draws, chains)
 
 
-def running_on_ci() -> bool:
-    """Return True if running on CI machine."""
-    return os.environ.get("ARVIZ_CI_MACHINE") is not None
-
-
 def importorskip(
     modname: str, minversion: Optional[str] = None, reason: Optional[str] = None
 ) -> Any:
@@ -643,9 +638,9 @@ def importorskip(
     Example::
         docutils = pytest.importorskip("docutils")
     """
-    # ARVIZ_CI_MACHINE is True if tests run on CI, where ARVIZ_CI_MACHINE env variable exists
-    ARVIZ_CI_MACHINE = running_on_ci()
-    if not ARVIZ_CI_MACHINE:
+    # Unless ARVIZ_REQUIRE_ALL_DEPS is defined, tests that require a missing dependency are skipped
+    # if set, missing optional dependencies trigger failed tests.
+    if "ARVIZ_REQUIRE_ALL_DEPS" not in os.environ:
         return pytest.importorskip(modname=modname, minversion=minversion, reason=reason)
     import warnings