diff --git a/plan.py b/plan.py
index e69de29..0ca8ae1 100755
--- a/plan.py
+++ b/plan.py
@@ -0,0 +1,53 @@
+#!/usr/bin/env python3
+
+import satisfactory
+
+import fractions
+import collections
+
+if __name__ == '__main__':
+    recipes = satisfactory.Cookbook('data/recipes')
+
+    required = collections.defaultdict(fractions.Fraction)
+    remain = []
+
+    target_name = 'supercomputer'
+    target = recipes[target_name]
+    target_recipe = target['recipes'][0]
+
+    remain.append({
+        target_name: fractions.Fraction(
+            target_recipe['output'][target_name],
+            target_recipe['crafting_time']
+        )
+    })
+
+    while remain:
+        for dst_name, dst_rate in remain.pop().items():
+            required[dst_name] += dst_rate
+
+            dst = recipes[dst_name]
+            if recipes.is_resource(dst_name):
+                continue
+
+            dst_recipe = recipes[dst_name]['recipes'][0]
+            src_recipe = recipes[dst_name]['recipes'][0]
+
+            normal_rate = fractions.Fraction(
+                dst_recipe['output'][dst_name],
+                dst_recipe['crafting_time']
+            )
+
+            scale = dst_rate / normal_rate
+
+            for src_name, src_count in src_recipe['input'].items():
+                src_rate = fractions.Fraction(
+                    src_count,
+                    dst_recipe['crafting_time']
+                ) * scale
+                remain.append({src_name: src_rate})
+
+    print(required)
+
+    for name, rate in required.items():
+        machine = recipes[name]['machine']