diff --git a/eland/filter.py b/eland/filter.py
index f6d45f9..cf0387b 100644
--- a/eland/filter.py
+++ b/eland/filter.py
@@ -171,7 +171,7 @@ class NotNull(BooleanFilter):
 class ScriptFilter(BooleanFilter):
     def __init__(self, inline, lang=None, params=None):
         super().__init__()
-        script = {"inline": inline}
+        script = {"source": inline}
         if lang is not None:
             script["lang"] = lang
         if params is not None:
diff --git a/eland/series.py b/eland/series.py
index 2cfaeac..e31b54b 100644
--- a/eland/series.py
+++ b/eland/series.py
@@ -409,7 +409,7 @@ class Series(NDFrame):
         if isinstance(other, Series):
             # Need to use scripted query to compare to values
             painless = f"doc['{self.name}'].value > doc['{other.name}'].value"
-            return ScriptFilter(painless)
+            return ScriptFilter(painless, lang="painless")
         elif isinstance(other, (int, float)):
             return Greater(field=self.name, value=other)
         else:
@@ -419,7 +419,7 @@ class Series(NDFrame):
         if isinstance(other, Series):
             # Need to use scripted query to compare to values
             painless = f"doc['{self.name}'].value < doc['{other.name}'].value"
-            return ScriptFilter(painless)
+            return ScriptFilter(painless, lang="painless")
         elif isinstance(other, (int, float)):
             return Less(field=self.name, value=other)
         else:
@@ -429,7 +429,7 @@ class Series(NDFrame):
         if isinstance(other, Series):
             # Need to use scripted query to compare to values
             painless = f"doc['{self.name}'].value >= doc['{other.name}'].value"
-            return ScriptFilter(painless)
+            return ScriptFilter(painless, lang="painless")
         elif isinstance(other, (int, float)):
             return GreaterEqual(field=self.name, value=other)
         else:
@@ -439,7 +439,7 @@ class Series(NDFrame):
         if isinstance(other, Series):
             # Need to use scripted query to compare to values
             painless = f"doc['{self.name}'].value <= doc['{other.name}'].value"
-            return ScriptFilter(painless)
+            return ScriptFilter(painless, lang="painless")
         elif isinstance(other, (int, float)):
             return LessEqual(field=self.name, value=other)
         else:
@@ -449,7 +449,7 @@ class Series(NDFrame):
         if isinstance(other, Series):
             # Need to use scripted query to compare to values
             painless = f"doc['{self.name}'].value == doc['{other.name}'].value"
-            return ScriptFilter(painless)
+            return ScriptFilter(painless, lang="painless")
         elif isinstance(other, (int, float)):
             return Equal(field=self.name, value=other)
         elif isinstance(other, str):
@@ -461,7 +461,7 @@ class Series(NDFrame):
         if isinstance(other, Series):
             # Need to use scripted query to compare to values
             painless = f"doc['{self.name}'].value != doc['{other.name}'].value"
-            return ScriptFilter(painless)
+            return ScriptFilter(painless, lang="painless")
         elif isinstance(other, (int, float)):
             return NotFilter(Equal(field=self.name, value=other))
         elif isinstance(other, str):
diff --git a/eland/tests/operators/test_operators_pytest.py b/eland/tests/operators/test_operators_pytest.py
index 495d722..cf65821 100644
--- a/eland/tests/operators/test_operators_pytest.py
+++ b/eland/tests/operators/test_operators_pytest.py
@@ -44,11 +44,12 @@ class TestOperators:
         assert IsNull("a").build() == {"missing": {"field": "a"}}
         assert NotNull("a").build() == {"exists": {"field": "a"}}
         assert ScriptFilter(
-            'doc["num1"].value > params.param1', params={"param1": 5}
+            'doc["num1"].value > params.param1', lang="painless", params={"param1": 5}
         ).build() == {
             "script": {
                 "script": {
-                    "inline": 'doc["num1"].value > params.param1',
+                    "lang": "painless",
+                    "source": 'doc["num1"].value > params.param1',
                     "params": {"param1": 5},
                 }
             }