diff --git a/environment.yml b/environment.yml
index 688f9af..a37a719 100644
--- a/environment.yml
+++ b/environment.yml
@@ -4,6 +4,7 @@ channels:
   - conda-forge
 dependencies:
   - python=3.9
+  - numba
   - numpy
   - typing
   - root=6.26.06
diff --git a/src/whisk/_recipe.py b/src/whisk/_recipe.py
index dc9e2fa..4f11139 100644
--- a/src/whisk/_recipe.py
+++ b/src/whisk/_recipe.py
@@ -9,12 +9,13 @@
 # or submit itself to any jurisdiction.                                       #
 ###############################################################################
 
-from itertools import product as iterprod
-from itertools import permutations
-from numpy import prod
-from ROOT import RDataFrame
-from typing import Dict, List, Union
+import awkward as ak
+import itertools as it
+import numba as nb
+import numpy as np
+import os
 
+from typing import Dict, List, Union
 
 # Categories should look like
 #   []
@@ -23,14 +24,15 @@
 class recipe:
     def __init__(
         self,
-        data: RDataFrame,
+        data,
         categories: Union[List[str], Dict[str, str]],
         totals: bool = False
     ):
         self.data = data
         self.categories = categories
         self.default_to_fractions = not(totals)
-        self.total_events = data.Count().GetValue()
+        self.total_events = len(data)
+        self.maximum = 0
 
         self._recipe()
 
@@ -49,26 +51,28 @@ def __getitem__(
 
         return sum(values)
 
-    def _parse_filter(
+    #def max(
+    #    self
+    #):
+    #    return self.maximum
+
+    def _filter(
         self,
         key : List[str]
     ):
         assert len(self.categories.keys()) == len(key), "Category list and possible keys are different length"
-
-        filters = [f'{category[0]} == "{sub_key}"' for category, sub_key in zip(self.categories.items(), key)]
-
-        assert len(filters) > 0, "Filter not parsed correctly."
-        return " && ".join(filters)
+        return np.logical_and.reduce([self.data[category[0]] == sub_key for category, sub_key in zip(self.categories.items(), key)])
 
     def _recipe(self):
 
         self.proportions = {}
-        keys = iterprod(*self.categories.values())
+        keys = it.product(*self.categories.values())
         for key in keys:
-            filt = self._parse_filter(key)
-            count = self.data.Filter(filt).Count().GetValue()
-            value = count / self.data.Count().GetValue() if self.default_to_fractions else count
+            filt = self._filter(key)
+            count = len(self.data[filt])
+            value = count / self.total_events if self.default_to_fractions else count
             self.proportions[key] = value
+            if value > self.maximum: self.maximum = value
 
 
     def _convert_to_fractions(self):
diff --git a/src/whisk/_table.py b/src/whisk/_table.py
index cde3889..7080157 100644
--- a/src/whisk/_table.py
+++ b/src/whisk/_table.py
@@ -10,9 +10,9 @@
 ###############################################################################
 
 def table(
-    data: RDataFrame,
+    data,
     categories: Union[List[str], Dict[str, str]],
-    absolute:
+    absolute,
     output: bool = False,
     totals: bool = False,
 
diff --git a/src/whisk/_whisk.py b/src/whisk/_whisk.py
index 7e47ea7..7fb3aa0 100644
--- a/src/whisk/_whisk.py
+++ b/src/whisk/_whisk.py
@@ -9,55 +9,21 @@
 # or submit itself to any jurisdiction.                                       #
 ###############################################################################
 
+import awkward as ak
+import numba as nb
+import numpy as np
 import os
-
-from ROOT import RDataFrame
-from tempfile import TemporaryDirectory
 from typing import Dict, List, Union
 
 from ._recipe import recipe
 
 def whisk(
-    reference_data: RDataFrame,
-    combining_data: Dict[Union[str, List[str]], RDataFrame],
+    reference_data,
+    combining_data,#: Dict[Union[str, List[str]], ],
     categories: Union[List[str], Dict[str, str]],
 ):
 
     reference_recipe = recipe(reference_data, categories)
-    cdfs = []
-    with TemporaryDirectory() as tmpdir:
-        for n, (key, cdf) in enumerate(combining_data.items()):
-            cdf_path = os.path.join(
-                tmpdir,
-                f"combining_dataframe{n}.root"
-            )
-            cdf.Snapshot("temp_tree", cdf_path)
-            cdfs += [cdf_path]
-        whisked_data = RDataFrame("temp_tree", cdfs)
-
-    return whisked_data
-
-def _calculate_proportions(
-    data: RDataFrame,
-    categories: Union[List[str], Dict[str, str]]
-):
-    proportions = {}
-    if type(categories) == list:
-        return
-
-    for category, values in categories:
-        for value in values:
-            proportions.extend({
-                category:  {
-                    "total" : data.Filter(f"{category} == {value}").Count().getValue()
-                }
-            })
-
-    return
+    combine_data = (data[np.random.rand(len(data)) < reference_recipe[categories] / reference_recipe.maximum] for categories, data in combining_data.items())
 
-    {
-        "red" : {
-            "total" : 1,
-            "square" : {"total": 1}
-        }
-    }
\ No newline at end of file
+    return ak.concatenate(combine_data)
\ No newline at end of file
diff --git a/tests/test_recipe.py b/tests/test_recipe.py
index e1bf274..9638577 100644
--- a/tests/test_recipe.py
+++ b/tests/test_recipe.py
@@ -9,62 +9,52 @@
 # or submit itself to any jurisdiction.                                       #
 ###############################################################################
 
-from ROOT import RDataFrame
-from ROOT.Numba import Declare
-
-import whisk
-
+import awkward as ak
+#import numba as nb
+import numpy as np
 
+from typing import List, Union
 
-# To-do:
-# - Fix instability in generated sample
+import whisk
 
+#@nb.njit
+def generate_data(colours: Union[str, List[str]],
+                  shapes: Union[str, List[str]],
+                  size: int = 1000):
 
-def generate_rdataframe(categories):
-
-    rdf = RDataFrame(1000)
-    
-    colours = ["red", "yellow", "green", "blue"]
-    rdf = rdf.Define("colour_idx", f"std::floor(gRandom->Rndm() * {len(colours)})")
-    rdf = rdf.Define("colour",
-                     f"""
-                         std::vector<std::string> colours = {{"{'","'.join(colours)}"}};
-                         return colours[colour_idx];
-                     """)
-    
-    shapes = ["triangle", "rectangle", "square"]
-    rdf = rdf.Define("shape_idx", f"std::floor(gRandom->Rndm() * {len(shapes)})")
-    rdf = rdf.Define("shape",
-                     f"""
-                         std::vector<std::string> shapes = {{"{'","'.join(shapes)}"}};
-                         return shapes[shape_idx];
-                     """)
-
-    return rdf
+    if type(colours) == str: colours = [colours]
+    if type(shapes) == str: shapes = [shapes]
 
+    data = {}
 
+    data["colour"] = np.random.choice(colours, size=size)
+    data["shape"] = np.random.choice(shapes, size=size)
 
+    return ak.Array(data)
 
 def test_recipe():
     categories = {
         "colour" : ["red", "yellow", "green", "blue"],
         "shape" : ["triangle", "rectangle", "square"],
     }
-    rdf = generate_rdataframe(categories)
-    rec = whisk.recipe(rdf, categories)
+    data = generate_data(*categories.values())
+    recipe = whisk.recipe(data, categories)
     
-    total = rdf.Count().GetValue()
+    total = len(data)#, axis=None)
+    print(total)
 
-    print(rec["red"])
-    print(rec["triangle"])
-    print(rec["red", "triangle"])
+    print(f"{recipe['red']:.4f} +/- {np.sqrt(recipe['red'] / total):.4f}")
+    print(f"{recipe['triangle']:.4f} +/- {np.sqrt(recipe['triangle'] / total):.4f}")
+    print(f"{recipe['red', 'triangle']:.4f} +/- {np.sqrt(recipe['red', 'triangle'] / total):.4f}")
     #assert rec["red"] == rdf.Filter('colour == "red"').Count().GetValue() / total
     #assert rec["triangle"] == rdf.Filter('shape == "triangle"').Count().GetValue() / total
     #assert rec["red", "triangle"] == rdf.Filter('colour == "red" && shape == "triangle"').Count().GetValue() / total
     #assert rec["triangle", "red"] == rdf.Filter('colour == "red" && shape == "triangle"').Count().GetValue() / total
     #assert rec["blue", "triangle"] == rdf.Filter('colour == "blue" && shape == "triangle"').Count().GetValue() / total
     #assert rec["square", "red"] == rdf.Filter('colour == "red" && shape == "shape"').Count().GetValue() / total
-    
+
+
+"""
 def dummy(rec):
     test_indices = (["red", "triangle"],
                     ["triangle", "red"],
@@ -74,4 +64,5 @@ def dummy(rec):
     for test_index in test_indices:
         # [[lst[i] for i in pattern] for lst in a]
         count = [[rec[i] for i in test_indices]]
-        print(f"{test_index}: {count}")
\ No newline at end of file
+        print(f"{test_index}: {count}")
+"""
\ No newline at end of file
diff --git a/tests/test_whisk.py b/tests/test_whisk.py
index c043e01..37df2e8 100644
--- a/tests/test_whisk.py
+++ b/tests/test_whisk.py
@@ -9,58 +9,53 @@
 # or submit itself to any jurisdiction.                                       #
 ###############################################################################
 
-from itertools import product as iterprod
-from ROOT import RDataFrame
-from ROOT.Numba import Declare
+import awkward as ak
+import itertools as it
+#import numba as nb
+import numpy as np
+
 from typing import List, Union
 
 import whisk
 
 
+
 # To-do:
 # - Fix instability in generated sample
 
+def generate_data(colours: Union[str, List[str]],
+                  shapes: Union[str, List[str]],
+                  size: int = 1000):
 
-def generate_rdataframe(colours: Union[str, List[str]],
-                        shapes: Union[str, List[str]],
-                        size: int = 1000):
-
-    rdf = RDataFrame(size)
-    
-    rdf = rdf.Define("colour_idx", f"std::floor(gRandom->Rndm() * {len(colours)})")
-    rdf = rdf.Define("colour",
-                     f"""
-                         std::vector<std::string> colours = {{"{'","'.join(colours)}"}};
-                         return colours[colour_idx];
-                     """)
+    if type(colours) == str: colours = [colours]
+    if type(shapes) == str: shapes = [shapes]
 
-    rdf = rdf.Define("shape_idx", f"std::floor(gRandom->Rndm() * {len(shapes)})")
-    rdf = rdf.Define("shape",
-                     f"""
-                         std::vector<std::string> shapes = {{"{'","'.join(shapes)}"}};
-                         return shapes[shape_idx];
-                     """)
+    data = {}
 
-    return rdf
+    data["colour"] = np.random.choice(colours, size=size)
+    data["shape"] = np.random.choice(shapes, size=size)
 
+    return ak.Array(data)
 
 def test_whisk():
     ref_categories = {
         "colour" : ["red", "red", "red", "yellow", "yellow", "green", "blue"],
         "shape" : ["triangle", "triangle", "rectangle", "square"],
     }
-    ref_rdf = generate_rdataframe(ref_categories["colour"], ref_categories["shape"], size = 1000)
+    ref_data = generate_data(ref_categories["colour"], ref_categories["shape"], size = 1000)
 
     raw_categories = {
         "colour" : ["red", "yellow", "green", "blue"],
         "shape" : ["triangle", "rectangle", "square"],
     }
     
-    raw_rdfs = {}
-    for (colour, shape) in iterprod(*raw_categories.values()):
-        raw_rdfs[(colour,shape)] = generate_rdataframe(colour, shape, size=10000)
-    print(raw_rdfs["red", "triangle"])
-    print(raw_rdfs["red", "triangle"].Count().GetValue())
-    whisked_rdf = whisk.whisk(ref_rdf, raw_rdfs, raw_categories)
-    print(whisked_rdf.Count().GetValue())
-    print(whisked_rdf["red", "triangle"].Count().GetValue())
+    raw_data = {}
+    for (colour, shape) in it.product(*raw_categories.values()):
+        rd = generate_data(colour, shape, size=10000)
+        raw_data[(colour,shape)] = rd
+
+    print(len(raw_data["red", "triangle"]))
+    whisked_data = whisk.whisk(ref_data, raw_data, raw_categories)
+    print(len(whisked_data[whisked_data["colour"] == "red"]))
+    print(len(whisked_data[whisked_data["shape"] == "rectangle"]))
+    print(len(whisked_data[np.logical_and(whisked_data["colour"] == "red", whisked_data["shape"] == "rectangle")]))
\ No newline at end of file