diff --git a/src/test/java/emissary/core/TransformHistoryTest.java b/src/test/java/emissary/core/TransformHistoryTest.java
new file mode 100644
index 0000000000..b87883a36b
--- /dev/null
+++ b/src/test/java/emissary/core/TransformHistoryTest.java
@@ -0,0 +1,182 @@
+package emissary.core;
+
+import emissary.test.core.junit5.UnitTest;
+
+import org.junit.jupiter.api.Test;
+
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class TransformHistoryTest extends UnitTest {
+
+    @Test
+    void testSet() {
+        String key1 = "UNKNOWN.FILE_PICK_UP.INPUT.http://localhost:8001/FilePickUpPlace$5050";
+        String key2 = "KNOWN.COOL_STUFF.TRANSFORM.http://localhost:8001/CoolStuffPlace$5050";
+        String key3 = "KNOWN.ONE_THING.ANALYZE.http://localhost:8001/DoOneThingPlace$5050";
+        String key4 = "KNOWN.LAST_PLACE.VERIFY.http://localhost:8001/LastThingPlace$5050";
+
+        var keySet1 = List.of(key1, key2);
+        var keySet2 = List.of(key3, key4);
+
+        // create, set and check the history
+        TransformHistory th = new TransformHistory();
+        th.set(keySet1);
+        assertEquals(2, th.getHistory().size());
+        assertTrue(th.get().contains(key1));
+        assertTrue(th.get().contains(key2));
+
+        // re-set and check that history is cleared
+        th.set(keySet2);
+        assertEquals(2, th.getHistory().size());
+        assertTrue(th.get().contains(key3));
+        assertTrue(th.get().contains(key4));
+
+        // set using object
+        TransformHistory historyObject = new TransformHistory();
+        historyObject.set(keySet1);
+        th.set(historyObject);
+        assertEquals(2, th.getHistory().size());
+        assertTrue(th.get().contains(key1));
+        assertTrue(th.get().contains(key2));
+
+        // create using object
+        TransformHistory newHistory = new TransformHistory(historyObject);
+        assertEquals(2, newHistory.getHistory().size());
+        assertTrue(newHistory.get().contains(key1));
+        assertTrue(newHistory.get().contains(key2));
+    }
+
+    @Test
+    void testAppend() {
+        String key1 = "UNKNOWN.FILE_PICK_UP.INPUT.http://localhost:8001/FilePickUpPlace$5050";
+        String key2 = "KNOWN.COOL_STUFF.COORDINATE.http://localhost:8001/CoolStuffPlace$5050";
+        String key3 = "KNOWN.ONE_THING.ANALYZE.http://localhost:8001/DoOneThingPlace$5050";
+        var keyList = List.of(key1);
+
+        // create and seed a transform history
+        TransformHistory th = new TransformHistory();
+        th.set(keyList);
+        assertEquals(1, th.getHistory().size());
+        assertTrue(th.get().contains(key1));
+
+        // now append a value
+        th.append(key2);
+        assertEquals(2, th.getHistory().size());
+        assertTrue(th.get().contains(key2));
+        assertFalse(th.getHistory().get(1).wasCoordinated());
+
+        // now append a coordinated value
+        th.append(key3, true);
+        assertEquals(3, th.getHistory().size());
+        assertFalse(th.get().contains(key3)); // does not include coordinated results
+        assertTrue(th.get(true).contains(key3));
+        assertTrue(th.getHistory().get(2).wasCoordinated());
+    }
+
+    @Test
+    void testVisitation() {
+        String key1 = "UNKNOWN.FILE_PICK_UP.INPUT.http://localhost:8001/FilePickUpPlace$5050";
+        String key2 = "KNOWN.COOL_STUFF.COORDINATE.http://localhost:8001/CoolStuffPlace$5050";
+        String key3 = "KNOWN.ONE_THING.ANALYZE.http://localhost:8001/DoOneThingPlace$5050";
+        String key4 = "KNOWN.LAST_PLACE.VERIFY.http://localhost:8001/LastThingPlace$5050";
+
+        TransformHistory th = new TransformHistory();
+
+        // set and check the history when last place visited was coordinated
+        th.append(key1);
+        th.append(key2);
+        th.append(key3, true);
+        assertEquals(3, th.getHistory().size());
+
+        assertEquals(key2, th.lastVisit()); // skips the coordinated place
+        assertEquals(key1, th.penultimateVisit());
+
+        // set and check the history with the last place visited was not coordinated
+        th.append(key4);
+        assertEquals(4, th.getHistory().size());
+
+        assertEquals(key4, th.lastVisit());
+        assertEquals(key2, th.penultimateVisit()); // skips the coordinated place
+
+        // check if a place has been visited
+        assertFalse(th.hasVisited("*.ONE_THING.*.*")); // coordinated place is ignored
+        assertTrue(th.hasVisited("*.LAST_PLACE.*.*"));
+        assertFalse(th.hasVisited("*.NEVER_PLACE.*.*"));
+
+        // clear and check for null
+        th.clear();
+        assertNull(th.lastVisit());
+        assertNull(th.penultimateVisit());
+    }
+
+    @Test
+    void testBeforeStart() {
+        String key1 = "UNKNOWN.FILE_PICK_UP.INPUT.http://localhost:8001/FilePickUpPlace$5050";
+        String key2 = "KNOWN.COOL_STUFF.TRANSFORM.http://localhost:8001/CoolStuffPlace$5050";
+        String key3 = "*.*.<SPROUT>.http://localhost:8001/CoolStuffPlace$0";
+        String key4 = "KNOWN.LAST_PLACE.VERIFY.http://localhost:8001/LastThingPlace$5050";
+        var keyList = List.of(key1, key2, key3);
+
+        TransformHistory th = new TransformHistory();
+
+        // empty should return true
+        assertTrue(th.beforeStart());
+
+        // just one key, no sprout
+        th.append(key1);
+        assertFalse(th.beforeStart());
+
+        // history with a sprout as the last item
+        th.set(keyList);
+        assertTrue(th.beforeStart());
+
+        // processing after sprout
+        th.append(key4);
+        assertFalse(th.beforeStart());
+    }
+
+    @Test
+    void testToString() {
+        String key1 = "UNKNOWN.FILE_PICK_UP.INPUT.http://localhost:8001/FilePickUpPlace$5050";
+        String key2 = "KNOWN.COOL_STUFF.TRANSFORM.http://localhost:8001/CoolStuffPlace$5050";
+        String key3 = "*.*.<SPROUT>.http://localhost:8001/CoolStuffPlace$0";
+        String key4 = "KNOWN.COOL_STUFF.COORDINATE.http://localhost:8001/CoolStuffPlace$5050";
+        String key5 = "KNOWN.ONE_THING.ANALYZE.http://localhost:8001/DoOneThingPlace$5050";
+        String key6 = "KNOWN.LAST_PLACE.VERIFY.http://localhost:8001/LastThingPlace$5050";
+
+        String newline = System.getProperty("line.separator");
+        StringBuilder expected = new StringBuilder();
+        expected.append("transform history (6) :").append(newline);
+        expected.append("        -> ").append(key1).append(newline);
+        expected.append("        -> ").append(key2).append(newline);
+        expected.append("        -> ").append(key3).append(newline);
+        expected.append("        -> ").append(key4).append(newline);
+        expected.append("           +--> ").append(key5).append(newline);
+        expected.append("        -> ").append(key6).append(newline);
+
+        TransformHistory th = new TransformHistory();
+        th.append(key1);
+        th.append(key2);
+        th.append(key3);
+        th.append(key4);
+        th.append(key5, true);
+        th.append(key6);
+
+        assertEquals(expected.toString(), th.toString());
+    }
+
+    @Test
+    void testGetKeyNoUrl() {
+        String key1 = "UNKNOWN.FILE_PICK_UP.INPUT.http://localhost:8001/FilePickUpPlace$5050";
+
+        TransformHistory th = new TransformHistory();
+        th.append(key1);
+
+        assertEquals("UNKNOWN.FILE_PICK_UP.INPUT", th.getHistory().get(0).getKeyNoUrl());
+    }
+}