diff --git a/v3/api.py b/v3/api.py
new file mode 100644
index 0000000..5d1400f
--- /dev/null
+++ b/v3/api.py
@@ -0,0 +1,110 @@
+from entities import *
+from llm import *
+
+# Detect victory
+#
+# Conditions:
+# 1. Matching items have just been hidden and all items are hidden now
+@llm_by_value
+def memory_api_detectVictory(
+  c: MemoryContext
+) -> MemoryContext:
+  if (
+    c.recentField == "hiddenItems" and
+    len(c.hiddenItems) == len(c.playfieldItems)
+  ):
+    c.victory = True
+    c.recentField = "victory"
+    return c
+
+  c.recentField = None
+  return c
+#}
+
+# Deselect mismatched items
+#
+# Conditions:
+# 1. Two items are selected and they are of different groups
+@llm_by_value
+def memory_api_deselectMismatchedItems(
+  c: MemoryContext
+) -> MemoryContext:
+  if (
+    c.recentField == "selectedItems" and
+    len(c.selectedItems) == 2 and
+    c.playfieldItems[c.selectedItems[0]] != c.playfieldItems[c.selectedItems[1]]
+  ):
+    c.mismatchedItems.clear()
+    c.mismatchedItems.append(c.selectedItems[0])
+    c.mismatchedItems.append(c.selectedItems[1])
+    c.recentField = "mismatchedItems"
+    return c
+
+  c.recentField = None
+  return c
+#}
+
+# Generate constant playfield suitable for testing and debugging
+@llm_by_value
+def memory_api_generateConstPlayfield(
+  c: MemoryContext
+) -> MemoryContext:
+  idGroups: dict[int, int] = { }
+  id = 0
+  for gid in range(0, c.playfieldSize):
+    idGroups[id] = gid
+    id += 1
+    idGroups[id] = gid
+    id += 1
+  #}
+  c.playfieldItems = idGroups
+  c.recentField = "playfieldItems"
+  return c
+#}
+
+# Hide matching selected items
+#
+# Conditions:
+# 1. Two items are selected and they are of the same group
+@llm_by_value
+def memory_api_hideMatchingItems(
+  c: MemoryContext
+) -> MemoryContext:
+  if (
+    c.recentField == "selectedItems" and
+    len(c.selectedItems) == 2 and
+    c.playfieldItems[c.selectedItems[0]] == c.playfieldItems[c.selectedItems[1]]
+  ):
+    c.hiddenItems.append(c.selectedItems[0])
+    c.hiddenItems.append(c.selectedItems[1])
+    c.recentField = "hiddenItems"
+    return c
+
+  c.recentField = None
+  return c
+#}
+
+# Select item
+#
+# Conditions:
+# 1. There are already two selected items
+# 2. Item has just been selected
+@llm_by_value
+def memory_api_selectItem(
+  c: MemoryContext
+) -> MemoryContext:
+  if (
+    len(c.selectedItems) == 2
+  ):
+    c.selectedItems = []
+  
+  if (
+    c.recentField == "selectedId"
+  ):
+    c.selectedItems.append(c.selectedId)
+    c.recentField = "selectedItems"
+    return c
+
+  c.recentField = None
+  return c
+#}
diff --git a/v3/seq.py b/v3/seq.py
new file mode 100644
index 0000000..a8060be
--- /dev/null
+++ b/v3/seq.py
@@ -0,0 +1,231 @@
+from entities import *
+from llm import *
+
+# Execute selections and verify  
+#
+# Conditions:
+# 1. Matching items have just been hidden and all items are hidden now
+@llm_by_value
+def memory_api_detectVictory(
+  c: MemoryContext
+) -> MemoryContext:
+
+
+# Test.
+
+def test_memory_generateConstPlayfield(
+) -> str:
+  c = memory_createEmptyContext()
+  c.playfieldSize = 2
+  c = memory_generateConstPlayfield(c)
+  if (
+    c.recentField == "playfieldItems" and
+    len(c.playfieldItems) == 4 and
+    c.playfieldItems[0] == 0 and
+    c.playfieldItems[1] == 0 and
+    c.playfieldItems[2] == 1 and
+    c.playfieldItems[3] == 1
+  ):
+    return "OK: memory_generateConstPlayfield"
+  #}
+  return "ERR: memory_generateConstPlayfield"
+#}
+
+def test_memory_selectItem(
+) -> str:
+  c = memory_createEmptyContext()
+  c.playfieldSize = 2
+  c = memory_generateConstPlayfield(c)
+
+  # Select the first item.
+  c.selectedId = 0
+  c.recentField = "selectedId"
+  c = memory_selectItem(c)
+
+  # See if it's in selectedItems now.
+  if (
+    c.recentField == "selectedItems" and
+    len(c.selectedItems) == 1 and
+    c.selectedItems[0] == 0
+  ):
+    return "OK: selectItem"
+  #}
+  return "ERR: selectItem"
+#}
+
+def test_selectTwoItems(
+) -> str:
+  c = memory_createEmptyContext()
+  c.playfieldSize = 2
+  c = memory_generateConstPlayfield(c)
+
+  # Select the first two items.
+  c.selectedId = 0
+  c.recentField = "selectedId"
+  c = memory_selectItem(c)
+  c.selectedId = 1
+  c.recentField = "selectedId"
+  c = memory_selectItem(c)
+
+  # See if it's both items are selected now.
+  if (
+    c.recentField == "selectedItems" and
+    len(c.selectedItems) == 2 and
+    c.selectedItems[0] == 0 and
+    c.selectedItems[1] == 1
+  ):
+    return "OK: selectTwoItems"
+  #}
+  return "ERR: selectTwoItems"
+#}
+
+def test_selectThreeItems(
+) -> str:
+  c = memory_createEmptyContext()
+  c.playfieldSize = 2
+  c = memory_generateConstPlayfield(c)
+
+  # Select three items.
+  c.selectedId = 0
+  c.recentField = "selectedId"
+  c = memory_selectItem(c)
+  c.selectedId = 1
+  c.recentField = "selectedId"
+  c = memory_selectItem(c)
+  c.selectedId = 2
+  c.recentField = "selectedId"
+  c = memory_selectItem(c)
+
+  # See if only one (last) item is selected now.
+  if (
+    c.recentField == "selectedItems" and
+    len(c.selectedItems) == 1 and
+    c.selectedItems[0] == 2
+  ):
+    return "OK: selectThreeItems"
+  #}
+  return "ERR: selectThreeItems"
+#}
+
+def test_memory_hideMatchingItems(
+) -> str:
+  c = memory_createEmptyContext()
+  c.playfieldSize = 2
+  c = memory_generateConstPlayfield(c)
+
+  # Select two items of the same group.
+  c.selectedId = 0
+  c.recentField = "selectedId"
+  c = memory_selectItem(c)
+  c.selectedId = 1
+  c.recentField = "selectedId"
+  c = memory_selectItem(c)
+
+  # Hide matching items.
+  c = memory_hideMatchingItems(c)
+
+  # See if the two selected items match.
+  if (
+    c.recentField == "hiddenItems" and
+    len(c.hiddenItems) == 2 and
+    c.hiddenItems[0] == 0 and
+    c.hiddenItems[1] == 1
+  ):
+    return "OK: memory_hideMatchingItems"
+  #}
+  return "ERR: memory_hideMatchingItems"
+#}
+
+def test_memory_deselectMismatchedItems(
+) -> str:
+  c = memory_createEmptyContext()
+  c.playfieldSize = 2
+  c = memory_generateConstPlayfield(c)
+
+  # Select two items of different groups.
+  c.selectedId = 0
+  c.recentField = "selectedId"
+  c = memory_selectItem(c)
+  c.selectedId = 2
+  c.recentField = "selectedId"
+  c = memory_selectItem(c)
+
+  # Detect mismatching.
+  c = memory_deselectMismatchedItems(c)
+
+  # See if the two selected items do not match.
+  if (
+    c.recentField == "mismatchedItems" and
+    len(c.mismatchedItems) == 2 and
+    c.mismatchedItems[0] == 0 and
+    c.mismatchedItems[1] == 2
+  ):
+    return "OK: memory_deselectMismatchedItems"
+  #}
+  return "ERR: memory_deselectMismatchedItems"
+#}
+
+def test_memory_detectVictory(
+) -> str:
+  c = memory_createEmptyContext()
+  c.playfieldSize = 2
+  c = memory_generateConstPlayfield(c)
+
+  # Select the first two items of the same group.
+  c.selectedId = 0
+  c.recentField = "selectedId"
+  c = memory_selectItem(c)
+  c.selectedId = 1
+  c.recentField = "selectedId"
+  c = memory_selectItem(c)
+
+  # Hide the first pair.
+  c = memory_hideMatchingItems(c)
+
+  # Select the last two items of the same group.
+  c.selectedId = 2
+  c.recentField = "selectedId"
+  c = memory_selectItem(c)
+  c.selectedId = 3
+  c.recentField = "selectedId"
+  c = memory_selectItem(c)
+
+  # Hide the second pair.
+  c = memory_hideMatchingItems(c)
+
+  # Detect victory.
+  c = memory_detectVictory(c)
+
+  # See if victory has been detected.
+  if (
+    c.recentField == "victory" and
+    c.victory == True
+  ):
+    return "OK: memory_detectVictory"
+  #}
+  return "ERR: memory_detectVictory"
+#}
+
+def test_passContextByValue(
+) -> str:
+  c = memory_createEmptyContext()
+  c.playfieldSize = 2
+  c = memory_generateConstPlayfield(c)
+
+  c.selectedId = 0
+  c.recentField = "selectedId"
+  c1 = memory_selectItem(c)
+
+  c.selectedId = 1
+  c.recentField = "selectedId"
+  c2 = memory_selectItem(c)
+
+  # See if c1 and c2 have different recentField.
+  if (
+    c1.selectedId != c2.selectedId
+  ):
+    return "OK: passContextByValue"
+
+  return "ERR: passContextByValue"
+#}
+