From 102ff7cff39365d48e5915dab4feb09b24603584 Mon Sep 17 00:00:00 2001
From: Bouwe Andela <b.andela@esciencecenter.nl>
Date: Mon, 24 Nov 2025 15:47:42 +0100
Subject: [PATCH 1/2] Use recipe from conda environment

---
 .../src/climate_ref_esmvaltool/diagnostics/base.py |  8 +++++++-
 .../src/climate_ref_esmvaltool/recipe.py           | 14 +++++++++++++-
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/diagnostics/base.py b/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/diagnostics/base.py
index 8b8e3652b..d6bd4dc49 100644
--- a/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/diagnostics/base.py
+++ b/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/diagnostics/base.py
@@ -101,11 +101,17 @@ def write_recipe(self, definition: ExecutionDefinition) -> Path:
         :
             The path to the written recipe.
         """
+        recipe_dir = None
+        if (env_path := definition.diagnostic.provider.env_path).exists():  # type: ignore[attr-defined]
+            # Use the recipe from the conda environment if available.
+            subdir = Path("lib").joinpath("python*", "site-packages", "esmvaltool", "recipes")
+            if recipe_dirs := sorted(env_path.glob(str(subdir))):
+                recipe_dir = recipe_dirs[-1]
+        recipe = load_recipe(self.base_recipe, recipe_dir)
         input_files = {
             project: dataset_collection.datasets
             for project, dataset_collection in definition.datasets.items()
         }
-        recipe = load_recipe(self.base_recipe)
         self.update_recipe(recipe, input_files)
         recipe_txt = yaml.safe_dump(recipe, sort_keys=False)
         logger.info(f"Using ESMValTool recipe:\n{recipe_txt}")
diff --git a/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/recipe.py b/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/recipe.py
index 2cb6fb808..62101b4b4 100644
--- a/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/recipe.py
+++ b/packages/climate-ref-esmvaltool/src/climate_ref_esmvaltool/recipe.py
@@ -6,6 +6,7 @@
 
 import pooch
 import yaml
+from loguru import logger
 
 from climate_ref_esmvaltool.types import Recipe
 
@@ -160,19 +161,30 @@ def dataframe_to_recipe(
     _RECIPES.load_registry(_buffer)
 
 
-def load_recipe(recipe: str) -> Recipe:
+def load_recipe(recipe: str, path: Path | None) -> Recipe:
     """Load a recipe.
 
     Parameters
     ----------
     recipe
         The name of an ESMValTool recipe.
+    path:
+        The path where the ESMValTool recipes are located. If None, use the
+        default path for the recipe registry.
 
     Returns
     -------
         The loaded recipe.
     """
+    if path is not None:
+        # Override default registry path.
+        previous_path = _RECIPES.path  # type: ignore[attr-defined]
+        _RECIPES.path = path  # type: ignore[attr-defined]
     filename = _RECIPES.fetch(recipe)
+    if path is not None:
+        # Restore previous registry path.
+        _RECIPES.path = previous_path  # type: ignore[attr-defined]
+    logger.info(f"Updating recipe from {filename}")
 
     def normalize(obj: Any) -> Any:
         # Ensure objects in the recipe are not shared.

From 0be7e6b008c18ffcba797b0f82ce5fa8eb29e6df Mon Sep 17 00:00:00 2001
From: Bouwe Andela <b.andela@esciencecenter.nl>
Date: Mon, 24 Nov 2025 15:52:02 +0100
Subject: [PATCH 2/2] Add changelog

---
 changelog/471.improvement.md | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 changelog/471.improvement.md

diff --git a/changelog/471.improvement.md b/changelog/471.improvement.md
new file mode 100644
index 000000000..59a0e853d
--- /dev/null
+++ b/changelog/471.improvement.md
@@ -0,0 +1 @@
+Use ESMValTool recipes from the conda environment if it is available.