diff --git a/capa/engine.py b/capa/engine.py
index d7ff81f6..601ddd34 100644
--- a/capa/engine.py
+++ b/capa/engine.py
@@ -87,11 +87,11 @@ class And(Statement):
 
     def evaluate(self, ctx):
         capa.perf.counters["evaluate.feature"] += 1
-        capa.perf.counters["evaluate.feature.and"] += 1  
+        capa.perf.counters["evaluate.feature.and"] += 1
 
         results = []
         for child in self.children:
-            result = child.evaluate(ctx) 
+            result = child.evaluate(ctx)
             results.append(result)
             if not result:
                 # short circuit
@@ -103,7 +103,7 @@ class And(Statement):
 class Or(Statement):
     """
     match if any of the children evaluate to True.
- 
+
     the order of evaluation is dicated by the property
     `Or.children` (type: List[Statement|Feature]).
     a query optimizer may safely manipulate the order of these children.
@@ -115,7 +115,7 @@ class Or(Statement):
 
     def evaluate(self, ctx):
         capa.perf.counters["evaluate.feature"] += 1
-        capa.perf.counters["evaluate.feature.or"] += 1  
+        capa.perf.counters["evaluate.feature.or"] += 1
 
         results = []
         for child in self.children:
@@ -137,8 +137,8 @@ class Not(Statement):
 
     def evaluate(self, ctx):
         capa.perf.counters["evaluate.feature"] += 1
-        capa.perf.counters["evaluate.feature.not"] += 1  
-  
+        capa.perf.counters["evaluate.feature.not"] += 1
+
         results = [self.child.evaluate(ctx)]
         success = not results[0]
         return Result(success, self, results)
@@ -160,8 +160,8 @@ class Some(Statement):
 
     def evaluate(self, ctx):
         capa.perf.counters["evaluate.feature"] += 1
-        capa.perf.counters["evaluate.feature.some"] += 1  
- 
+        capa.perf.counters["evaluate.feature.some"] += 1
+
         results = []
         for child in self.children:
             result = child.evaluate(ctx)
@@ -184,8 +184,8 @@ class Range(Statement):
 
     def evaluate(self, ctx):
         capa.perf.counters["evaluate.feature"] += 1
-        capa.perf.counters["evaluate.feature.range"] += 1  
-  
+        capa.perf.counters["evaluate.feature.range"] += 1
+
         count = len(ctx.get(self.child, []))
         if self.min == 0 and count == 0:
             return Result(True, self, [])
diff --git a/capa/features/common.py b/capa/features/common.py
index 0f01ef52..a40201e3 100644
--- a/capa/features/common.py
+++ b/capa/features/common.py
@@ -190,7 +190,7 @@ class Substring(String):
 
     def evaluate(self, ctx):
         capa.perf.counters["evaluate.feature"] += 1
-        capa.perf.counters["evaluate.feature.substring"] += 1 
+        capa.perf.counters["evaluate.feature.substring"] += 1
 
         # mapping from string value to list of locations.
         # will unique the locations later on.
@@ -278,8 +278,8 @@ class Regex(String):
 
     def evaluate(self, ctx):
         capa.perf.counters["evaluate.feature"] += 1
-        capa.perf.counters["evaluate.feature.regex"] += 1 
-                                                        
+        capa.perf.counters["evaluate.feature.regex"] += 1
+
         # mapping from string value to list of locations.
         # will unique the locations later on.
         matches = collections.defaultdict(list)
@@ -364,8 +364,8 @@ class Bytes(Feature):
 
     def evaluate(self, ctx):
         capa.perf.counters["evaluate.feature"] += 1
-        capa.perf.counters["evaluate.feature.bytes"] += 1 
-                                                        
+        capa.perf.counters["evaluate.feature.bytes"] += 1
+
         for feature, locations in ctx.items():
             if not isinstance(feature, (Bytes,)):
                 continue
diff --git a/capa/rules.py b/capa/rules.py
index 038f4d73..b49f7ee1 100644
--- a/capa/rules.py
+++ b/capa/rules.py
@@ -622,7 +622,7 @@ class Rule:
 
     def evaluate(self, features: FeatureSet):
         capa.perf.counters["evaluate.feature"] += 1
-        capa.perf.counters["evaluate.feature.rule"] += 1 
+        capa.perf.counters["evaluate.feature.rule"] += 1
         return self.statement.evaluate(features)
 
     @classmethod
@@ -1053,7 +1053,7 @@ class RuleSet:
         #
         # this should be all hash-lookup features.
         # see below.
- 
+
         elif isinstance(node, (capa.features.common.Substring, capa.features.common.Regex)):
             # substring and regex features require a full scan of each string
             # which we anticipate is more expensive then a hash lookup feature (e.g. mnemonic or count).
@@ -1070,7 +1070,7 @@ class RuleSet:
             # the cost of these nodes is the full cost of their children
             # as this is the worst-case scenario.
             return sum(map(RuleSet._get_node_cost, node.children))
-        
+
         else:
             # this should be all hash-lookup features.
             # we give this a arbitrary weight of 1.