diff --git a/src/Extensions/ContainsKey.cs b/src/Extensions/ContainsKey.cs
deleted file mode 100644
index 639c9033..00000000
--- a/src/Extensions/ContainsKey.cs
+++ /dev/null
@@ -1,24 +0,0 @@
-using Bonsai;
-using System;
-using System.ComponentModel;
-using System.Collections.Generic;
-using System.Linq;
-using System.Reactive.Linq;
-
-[Combinator]
-[Description("Returns true if the dictionary contains the specified key.")]
-[WorkflowElementCategory(ElementCategory.Transform)]
-public class ContainsKey
-{
-    private string key;
-    public string Key
-    {
-        get { return key; }
-        set { key = value; }
-    }
-
-    public IObservable<bool> Process<TValue>(IObservable<IDictionary<string, TValue>> source)
-    {
-        return source.Select(value => {return value.ContainsKey(Key);});
-    }
-}
diff --git a/src/Extensions/SinkSoftwareEvent.bonsai b/src/Extensions/SinkSoftwareEvent.bonsai
deleted file mode 100644
index ea4a0864..00000000
--- a/src/Extensions/SinkSoftwareEvent.bonsai
+++ /dev/null
@@ -1,66 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<WorkflowBuilder Version="2.8.1"
-                 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-                 xmlns:rx="clr-namespace:Bonsai.Reactive;assembly=Bonsai.Core"
-                 xmlns:p1="clr-namespace:AllenNeuralDynamics.Core.Logging;assembly=AllenNeuralDynamics.Core"
-                 xmlns="https://bonsai-rx.org/2018/workflow">
-  <Workflow>
-    <Nodes>
-      <Expression xsi:type="WorkflowInput">
-        <Name>Source1</Name>
-      </Expression>
-      <Expression xsi:type="ExternalizedMapping">
-        <Property Name="EventName" />
-      </Expression>
-      <Expression xsi:type="rx:SelectMany">
-        <Name>SinkSoftwareEvent</Name>
-        <Workflow>
-          <Nodes>
-            <Expression xsi:type="WorkflowInput">
-              <Name>Source1</Name>
-            </Expression>
-            <Expression xsi:type="ExternalizedMapping">
-              <Property Name="EventName" />
-            </Expression>
-            <Expression xsi:type="Combinator">
-              <Combinator xsi:type="p1:CreateSoftwareEvent">
-                <p1:EventName>SoftwareEvent</p1:EventName>
-              </Combinator>
-            </Expression>
-            <Expression xsi:type="MulticastSubject">
-              <Name>SoftwareEvent</Name>
-            </Expression>
-            <Expression xsi:type="Combinator">
-              <Combinator xsi:type="rx:WithLatestFrom" />
-            </Expression>
-            <Expression xsi:type="MemberSelector">
-              <Selector>Item2</Selector>
-            </Expression>
-            <Expression xsi:type="Combinator">
-              <Combinator xsi:type="rx:Take">
-                <rx:Count>1</rx:Count>
-              </Combinator>
-            </Expression>
-            <Expression xsi:type="WorkflowOutput" />
-          </Nodes>
-          <Edges>
-            <Edge From="0" To="2" Label="Source1" />
-            <Edge From="0" To="4" Label="Source2" />
-            <Edge From="1" To="2" Label="Source2" />
-            <Edge From="2" To="3" Label="Source1" />
-            <Edge From="3" To="4" Label="Source1" />
-            <Edge From="4" To="5" Label="Source1" />
-            <Edge From="5" To="6" Label="Source1" />
-            <Edge From="6" To="7" Label="Source1" />
-          </Edges>
-        </Workflow>
-      </Expression>
-      <Expression xsi:type="WorkflowOutput" />
-    </Nodes>
-    <Edges>
-      <Edge From="0" To="2" Label="Source1" />
-      <Edge From="1" To="2" Label="Source2" />
-      <Edge From="2" To="3" Label="Source1" />
-    </Edges>
-  </Workflow>
-</WorkflowBuilder>
\ No newline at end of file