diff --git a/recipes.py b/recipes.py
index 55ed303..9984c07 100644
--- a/recipes.py
+++ b/recipes.py
@@ -1,10 +1,187 @@
-from typing import Dict, List, Any
+from typing import Dict, List, Any, Optional
+from dataclasses import dataclass
 import os
 
 import yaml
 import jinja2
 
 
+class Unit:
+    def __init__(self, name: str) -> None:
+        self.name = name
+
+class Units:
+    def __init__(self) -> None:
+        self.units: List[Unit] = []
+
+    def load(self, lst: List[Any]) -> List[str]:
+        assert_list(lst)
+        for unit in lst:
+            assert_type(unit, "", str)
+            self.units.append(Unit(unit))
+        return []
+
+    def get(self, name: str) -> Optional[Unit]:
+        for unit in self.units:
+            if unit.name == name:
+                return unit
+        raise RuntimeError(f"unit {name} not found")
+
+
+class Ingredient:
+    def load(self, dct: Dict[str, Any]) -> List[str]:
+        issues = []
+        issues += assert_dict(dct, ["name"], ["wdid", "pricedb"])
+
+        assert_type(dct, "name", str)
+        self.name = dct["name"]
+
+        self.wdid = -1
+        if "wdid" in dct:
+            assert_type(dct, "wdid", int)
+            self.wdid = dct["wdid"]
+
+        self.pricedb = None
+        if "pricedb" in dct:
+            assert_list(dct["pricedb"])
+            self.pricedb = PriceDBs()
+            issues += self.pricedb.load(dct["pricedb"])
+
+        return issues
+
+
+class Ingredients:
+    def __init__(self) -> None:
+        self.ingredients: List[Ingredient] = []
+
+    def load(self, lst: List[Any]) -> List[str]:
+        issues = []
+        assert_list(lst)
+        for ingdct in lst:
+            ing = Ingredient()
+            issues += ing.load(ingdct)
+            self.ingredients.append(ing)
+        return issues
+
+    def get(self, name: str) -> Optional[Ingredient]:
+        for ing in self.ingredients:
+            if ing.name == name:
+                return ing
+        raise RuntimeError(f"ingredient {name} not found")
+
+
+class PriceDBs:
+    def __init__(self) -> None:
+        self.pricedbs: List[PriceDB] = []
+
+    def load(self, lst: List[Any]) -> List[str]:
+        issues = []
+        assert_list(lst)
+        for elem in lst:
+            pricedb = PriceDB()
+            issues += pricedb.load(elem)
+            self.pricedbs.append(pricedb)
+        return issues
+
+
+class PriceDB:
+    def load(self, dct: Dict[str, Any]) -> List[str]:
+        issues = []
+        issues += assert_dict(dct, ["price"], ["amount", "unit"])
+
+        if isinstance(dct["price"], float):
+            self.price = dct["price"]
+        elif isinstance(dct["price"], int):
+            self.price = float(dct["price"])
+        else:
+            raise RuntimeError(f"{dct['price']} has to be int or float")
+
+        self.amount = 1.0
+        if "amount" in dct:
+            if isinstance(dct["amount"], float):
+                self.amount = dct["amount"]
+            elif isinstance(dct["amount"], int):
+                self.amount = float(dct["amount"])
+            else:
+                raise RuntimeError(f"{dct['amount']} has to be int or float")
+
+        self.unit = None
+        if "unit" in dct:
+            assert_type(dct, "unit", str)
+            self.unit = units.get(dct["unit"])
+        return issues
+
+
+class IngredientInstance:
+    def load(self, dct: Dict[str, Any]) -> List[str]:
+        issues = []
+        issues += assert_dict(dct, ["name"], ["amount", "unit", "note"])
+
+        assert_type(dct, "name", str)
+        self.name = dct["name"]
+
+        self.ingredient = ingredients.get(self.name)
+
+        self.amount = 1.0
+        if "amount" in dct:
+            if isinstance(dct["amount"], float):
+                self.amount = dct["amount"]
+            elif isinstance(dct["amount"], int):
+                self.amount = float(dct["amount"])
+            else:
+                raise RuntimeError(f"{dct['amount']} has to be int or float")
+
+        self.unit = None
+        if "unit" in dct:
+            assert_type(dct, "unit", str)
+            self.unit = units.get(dct["unit"])
+
+        self.note = ""
+        if "note" in dct:
+            assert_type(dct, "note", str)
+            self.note = dct["note"]
+
+        return issues
+
+
+class RecipePart:
+    def load(self, dct: Dict[str, Any]) -> List[str]:
+        issues = []
+        issues += assert_dict(dct, ["title", "ingredients", "steps"], [])
+
+        assert_type(dct, "title", str)
+        self.title = dct["title"]
+
+        assert_type(dct, "ingredients", list)
+        self.ingredients: List[IngredientInstance] = []
+        for ing in dct["ingredients"]:
+            ingredient = IngredientInstance()
+            issues += ingredient.load(ing)
+            self.ingredients.append(ingredient)
+
+        assert_type(dct, "steps", list)
+        for elem in dct["steps"]:
+            assert_type(elem, "", str)
+        self.steps: List[str] = dct["steps"]
+
+        return issues
+
+
+class Recipe:
+    def __init__(self) -> None:
+        self.parts: List[RecipePart] = []
+        self.srcpath = ""
+        self.outpath = ""
+        self.title = ""
+
+    def load(self, dct: Dict[str, Any]) -> List[str]:
+        rp = RecipePart()
+        issues = rp.load(dct)
+        self.parts = [rp]
+        self.title = rp.title
+        return issues
+
+
 def load_file(file: str) -> Any:
     print(f"loading {file}")
     with open(file, encoding="utf-8") as f:
@@ -27,86 +204,17 @@ def assert_dict(
     return issues
 
 
-def assert_type(dct: Dict[str, Any], key: str, type: type) -> List[str]:
+def assert_type(dct: Dict[str, Any], key: str, type: type) -> None:
     if key == "":
         if not isinstance(dct, type):
-            return [f"{key} has to be a {type}"]
+            raise RuntimeError(f"{key} has to be a {type}")
     elif key in dct and not isinstance(dct[key], type):
-        return [f"{key} has to be a {type}"]
-    return []
+        raise RuntimeError(f"{key} has to be a {type}")
 
 
-def validate_units(units: List[Any]) -> List[str]:
-    if not isinstance(units, list):
-        raise RuntimeError(f"{units} has to be a list")
-    issues = []
-    for unit in units:
-        issues += assert_type(unit, "", str)
-    return issues
-
-
-def validate_ingredients(ingredients: Any) -> List[str]:
-    if not isinstance(ingredients, list):
-        raise RuntimeError(f"{ingredients} has to be a list")
-    issues = []
-    for ing in ingredients:
-        issues += assert_dict(ing, ["name"], ["wdid"])
-        issues += assert_type(ing, "name", str)
-    return issues
-
-
-def validate_recipe(recipe: Any, units: List[Any], ingredients: List[Any]) -> List[str]:
-    issues = []
-    issues += assert_dict(recipe, ["title", "ingredients", "steps"], [])
-
-    issues += assert_type(recipe, "title", str)
-    if not isinstance(recipe["ingredients"], list):
-        raise RuntimeError(f'{recipe["ingredients"]} has to be a list')
-    if not isinstance(recipe["steps"], list):
-        raise RuntimeError(f'{recipe["steps"]} has to be a list')
-
-    for ingredient in recipe["ingredients"]:
-        issues += assert_dict(ingredient, ["name"], ["amount", "unit", "note"])
-        issues += assert_type(ingredient, "name", str)
-        if (
-            "amount" in ingredient
-            and not isinstance(ingredient["amount"], int)
-            and not isinstance(ingredient["amount"], float)
-        ):
-            issues.append("each ingredient has to have a int or float amount")
-        issues += assert_type(ingredient, "unit", str)
-        issues += assert_type(ingredient, "note", str)
-        if ingredient["name"] not in [ing["name"] for ing in ingredients]:
-            issues.append(f"unknown ingredient {ingredient['name']}")
-
-    for step in recipe["steps"]:
-        if not isinstance(step, str):
-            issues.append("each step has to be a string")
-    return issues
-
-
-def get_recipes(units: List[Any], ingredients: List[Any]) -> List[Any]:
-    recipes = []
-    for _, _, files in os.walk("recipes/recipes"):
-        files.sort()
-        for file in files:
-            recipe = load_file("recipes/recipes/" + file)
-            try:
-                issues = validate_recipe(recipe, units, ingredients)
-            except RuntimeError as e:
-                print("WARNING:", e, "skipping")
-                continue
-            if len(issues) != 0:
-                for issue in issues:
-                    print("WARNING:", file, issue, "skipping")
-                continue
-            recipe["srcpath"] = file
-            if not file.endswith(".yaml"):
-                print(f"unknown extension of {file}")
-                continue
-            recipe["outpath"] = file[:-5] + ".html"
-            recipes.append(recipe)
-    return recipes
+def assert_list(lst: List[Any]) -> None:
+    if not isinstance(lst, list):
+        raise RuntimeError(f"{lst} has to be a {list}")
 
 
 def rendertemplate(
@@ -129,20 +237,45 @@ def rendertemplate(
         f.write(outstr)
 
 
-def main() -> None:
-    issues = []
-    units = load_file("recipes/units.yaml")
-    issues += validate_units(units)
+units = Units()
+ingredients = Ingredients()
 
-    ingredients = load_file("recipes/ingredients.yaml")
-    issues += validate_ingredients(ingredients)
+
+def main() -> None:
+    issues: List[str] = []
+
+    unitsdct = load_file("recipes/units.yaml")
+    issues += units.load(unitsdct)
+
+    ingredientsdct = load_file("recipes/ingredients.yaml")
+    issues += ingredients.load(ingredientsdct)
 
     if len(issues) != 0:
         for issue in issues:
             print("ERROR", issue)
         return
 
-    recipes = get_recipes(units, ingredients)
+    files = []
+    for _, _, filesx in os.walk("recipes/recipes"):
+        files = filesx
+        files.sort()
+
+    recipes: List[Recipe] = []
+    for file in files:
+        if not file.endswith(".yaml"):
+            print(f"unknown extension of {file}")
+            continue
+        recipe = Recipe()
+        recipedct = load_file("recipes/recipes/" + file)
+        issues += recipe.load(recipedct)
+        recipe.srcpath = file
+        recipe.outpath = file[:-5] + ".html"
+        recipes.append(recipe)
+
+    if len(issues) != 0:
+        for issue in issues:
+            print("ERROR", issue)
+        return
 
     env = jinja2.Environment(
         loader=jinja2.FileSystemLoader("templates"),
@@ -154,7 +287,7 @@ def main() -> None:
 
     recipetemplate = env.get_template("recipe.html")
     for recipe in recipes:
-        rendertemplate(recipetemplate, "html", recipe["outpath"], recipe)
+        rendertemplate(recipetemplate, "html", recipe.outpath, {"recipe": recipe})
 
 
 if __name__ == "__main__":
diff --git a/templates/recipe.html b/templates/recipe.html
index 5bfcd9e..bda1b65 100644
--- a/templates/recipe.html
+++ b/templates/recipe.html
@@ -1,19 +1,21 @@
 <!DOCTYPE html>
 <html lang="en">
 <head>
-    <title>{{title}}</title>
+    <title>{{recipe.title}}</title>
     <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/water.css@2/out/water.css">
     <meta charset="utf-8"> 
 </head>
 <body>
-    <h1>{{title}}</h1>
+    <h1>{{recipe.title}}</h1>
+    {% for part in recipe.parts %}
     <h2>Ingredients</h2>
-    {% for ing in ingredients %}
-        <li>{{ing.amount}} {{ing.unit}} {{ ing.name }}</li>
+    {% for ing in part.ingredients %}
+        <li>{{ing.amount}} {{ing.unit.name}} {{ ing.name }}</li>
     {% endfor %}
     <h2>Steps</h2>
-    {% for step in steps %}
+    {% for step in part.steps %}
         <li>{{ step }}</li>
     {% endfor %}
+    {% endfor %}
 </body>
 </html>
\ No newline at end of file