diff --git a/.env.example b/.env.example
new file mode 100644
index 0000000..5870cdc
--- /dev/null
+++ b/.env.example
@@ -0,0 +1,7 @@
+# Example of an environment file for the CMIP-REF project
+# This allows for running the project in a development environment outside of a container
+
+CELERY_BROKER_URL=redis://localhost:6379/1
+
+REF_OUTPUT_ROOT=out
+REF_ESGF_ROOT=.esgpull/data
diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 067426f..6cb4de4 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -74,7 +74,9 @@ jobs:
           make fetch-test-data
       - name: Run tests
         run: |
+          cp .env.example .env
           uv run --package ref-core pytest packages/ref-core -r a -v --doctest-modules --cov=packages/ref-core/src --cov-report=term
+          uv run --package ref-celery pytest packages/ref-celery -r a -v --doctest-modules --cov=packages/ref-celery/src --cov-report=term
           uv run --package ref-metrics-example pytest packages/ref-metrics-example -r a -v --doctest-modules --cov=packages/ref-metrics-example/src --cov-report=term --cov-append
           uv run coverage xml
           # Run integration tests (without adding to the coverage)
diff --git a/Makefile b/Makefile
index b3e9a05..47e1bb5 100644
--- a/Makefile
+++ b/Makefile
@@ -38,11 +38,17 @@ ruff-fixes:  ## fix the code using ruff
 	uv run ruff format
 
 .PHONY: test-core
-test-core:  ## run the tests
+test-core:  ## run the tests for ref-core
 	uv run --package ref-core \
 		pytest packages/ref-core \
 		-r a -v --doctest-modules --cov=packages/ref-core/src
 
+.PHONY: test-celery
+test-celery:  ## run the tests for ref-celery
+	uv run --package ref-celery \
+		pytest packages/ref-celery \
+		-r a -v --doctest-modules --cov=packages/ref-celery/src
+
 .PHONY: test-metrics-example
 test-metrics-example:  ## run the tests
 	uv run --package ref-metrics-example \
@@ -56,7 +62,7 @@ test-integration:  ## run the integration tests
 		-r a -v
 
 .PHONY: test
-test: test-core test-metrics-example test-integration ## run the tests
+test: test-core test-celery test-metrics-example test-integration ## run the tests
 
 # Note on code coverage and testing:
 # If you want to debug what is going on with coverage, we have found
diff --git a/conftest.py b/conftest.py
index cc30b67..9377045 100644
--- a/conftest.py
+++ b/conftest.py
@@ -15,3 +15,20 @@ def esgf_data_dir() -> Path:
     pull = esgpull.Esgpull()
 
     return pull.config.paths.data
+
+
+@pytest.fixture
+def test_dataset(esgf_data_dir) -> Path:
+    return (
+        esgf_data_dir
+        / "CMIP6"
+        / "ScenarioMIP"
+        / "CSIRO"
+        / "ACCESS-ESM1-5"
+        / "ssp126"
+        / "r1i1p1f1"
+        / "Amon"
+        / "tas"
+        / "gn"
+        / "v20210318"
+    )
diff --git a/packages/ref-core/tests/unit/test_executor.py b/packages/ref-core/tests/unit/test_executor.py
index feec036..f9c60bf 100644
--- a/packages/ref-core/tests/unit/test_executor.py
+++ b/packages/ref-core/tests/unit/test_executor.py
@@ -1,6 +1,7 @@
 import pytest
 from ref_core.executor import Executor, ExecutorManager, run_metric
 from ref_core.executor.local import LocalExecutor
+from ref_core.metrics import TriggerInfo
 
 
 class TestExecutorManager:
@@ -29,10 +30,11 @@ def test_run_metric(self, configuration, mock_metric):
 
 
 @pytest.mark.parametrize("executor_name", ["local", None])
-def test_run_metric_local(monkeypatch, executor_name, mock_metric, provider, configuration):
+def test_run_metric_local(monkeypatch, executor_name, mock_metric, provider, configuration, test_dataset):
     if executor_name:
         monkeypatch.setenv("REF_EXECUTOR", executor_name)
-    result = run_metric("mock", provider, configuration=configuration)
+    trigger = TriggerInfo(dataset=test_dataset)
+    result = run_metric("mock", provider, configuration=configuration, trigger=trigger)
     assert result.successful
 
 
diff --git a/packages/ref-core/tests/unit/test_providers.py b/packages/ref-core/tests/unit/test_providers.py
index a9007cf..0931632 100644
--- a/packages/ref-core/tests/unit/test_providers.py
+++ b/packages/ref-core/tests/unit/test_providers.py
@@ -1,3 +1,4 @@
+import pytest
 from ref_core.metrics import Metric
 from ref_core.providers import MetricsProvider
 
@@ -18,6 +19,11 @@ def test_provider_register(self, mock_metric):
         assert "mock" in provider._metrics
         assert isinstance(provider.get("mock"), Metric)
 
+    def test_provider_register_invalid(self, mock_metric):
+        provider = MetricsProvider("provider_name", "v0.23")
+        with pytest.raises(ValueError):
+            provider.register("invalid")
+
     def test_provider_fixture(self, provider):
         assert provider.name == "mock_provider"
         assert provider.version == "v0.1.0"
diff --git a/packages/ref-metrics-example/tests/unit/test_metrics.py b/packages/ref-metrics-example/tests/unit/test_metrics.py
index ec6c963..9bb529b 100644
--- a/packages/ref-metrics-example/tests/unit/test_metrics.py
+++ b/packages/ref-metrics-example/tests/unit/test_metrics.py
@@ -1,27 +1,7 @@
-from pathlib import Path
-
-import pytest
 from ref_core.metrics import Configuration, TriggerInfo
 from ref_metrics_example.example import AnnualGlobalMeanTimeseries, calculate_annual_mean_timeseries
 
 
-@pytest.fixture
-def test_dataset(esgf_data_dir) -> Path:
-    return (
-        esgf_data_dir
-        / "CMIP6"
-        / "ScenarioMIP"
-        / "CSIRO"
-        / "ACCESS-ESM1-5"
-        / "ssp126"
-        / "r1i1p1f1"
-        / "Amon"
-        / "tas"
-        / "gn"
-        / "v20210318"
-    )
-
-
 def test_annual_mean(esgf_data_dir, test_dataset):
     annual_mean = calculate_annual_mean_timeseries(test_dataset)
 
diff --git a/ruff.toml b/ruff.toml
index 3351c69..7978890 100644
--- a/ruff.toml
+++ b/ruff.toml
@@ -29,7 +29,8 @@ ignore = [
 "test*.py" = [
     "D",  # Documentation not needed in tests
     "S101",  # S101 Use of `assert` detected
-    "PLR2004" # Magic value used in comparison
+    "PLR2004", # Magic value used in comparison
+    "PLR0913", # Too many arguments in function definition
 ]
 "conftest.py" = [
     "D",  # Documentation not needed in tests