diff --git a/plantuml/history/01_lower-both-values.puml b/plantuml/history/01_lower-both-values.puml
new file mode 100644
index 00000000..35715abe
--- /dev/null
+++ b/plantuml/history/01_lower-both-values.puml
@@ -0,0 +1,15 @@
+@startuml
+
+start
+note left
+    Do this for each item in the list.
+    An item has a name, a sell in value and a quality value
+end note
+
+-lower quality with 1
+
+-lower sell in with 1
+
+stop
+
+@enduml
diff --git a/plantuml/history/02_sell-by-passed.puml b/plantuml/history/02_sell-by-passed.puml
new file mode 100644
index 00000000..0c763688
--- /dev/null
+++ b/plantuml/history/02_sell-by-passed.puml
@@ -0,0 +1,19 @@
+@startuml
+
+start
+note left
+    Do this for each item in the list.
+    An item has a name, a sell in value and a quality value
+end note
+
+-lower quality with 1
+
+-lower sell in with 1
+
+if (sell in < 0) then (yes)
+    -lower quality with 1
+endif
+
+stop
+
+@enduml
diff --git a/plantuml/history/03_quality-never-negative.puml b/plantuml/history/03_quality-never-negative.puml
new file mode 100644
index 00000000..df7859ac
--- /dev/null
+++ b/plantuml/history/03_quality-never-negative.puml
@@ -0,0 +1,23 @@
+@startuml
+
+start
+note left
+    Do this for each item in the list.
+    An item has a name, a sell in value and a quality value
+end note
+
+if (quality > 0) then (yes)
+    -lower quality with 1
+endif
+
+-lower sell in with 1
+
+if (sell in < 0) then (yes)
+    if (quality > 0) then (yes)
+        -lower quality with 1
+    endif
+endif
+
+stop
+
+@enduml
diff --git a/plantuml/history/04_aged-brie.puml b/plantuml/history/04_aged-brie.puml
new file mode 100644
index 00000000..3a484fc4
--- /dev/null
+++ b/plantuml/history/04_aged-brie.puml
@@ -0,0 +1,31 @@
+@startuml
+
+start
+note left
+    Do this for each item in the list.
+    An item has a name, a sell in value and a quality value
+end note
+
+if (not "Aged Brie") then (yes)
+    if (quality > 0) then (yes)
+        -lower quality with 1
+    endif
+else (no)
+    -increase quality with 1
+endif
+
+-lower sell in with 1
+
+if (sell in < 0) then (yes)
+    if (not "Aged Brie") then (yes)
+        if (quality > 0) then (yes)
+            -lower quality with 1
+        endif
+    else (no)
+        -increase quality with 1
+    endif
+endif
+
+stop
+
+@enduml
diff --git a/plantuml/history/05_quality-max-50.puml b/plantuml/history/05_quality-max-50.puml
new file mode 100644
index 00000000..5200ca72
--- /dev/null
+++ b/plantuml/history/05_quality-max-50.puml
@@ -0,0 +1,35 @@
+@startuml
+
+start
+note left
+    Do this for each item in the list.
+    An item has a name, a sell in value and a quality value
+end note
+
+if (not "Aged Brie") then (yes)
+    if (quality > 0) then (yes)
+        -lower quality with 1
+    endif
+else (no)
+    if (quality < 50) then (yes)
+        -increase quality with 1
+    endif
+endif
+
+-lower sell in with 1
+
+if (sell in < 0) then (yes)
+    if (not "Aged Brie") then (yes)
+        if (quality > 0) then (yes)
+            -lower quality with 1
+        endif
+    else (no)
+        if (quality < 50) then (yes)
+            -increase quality with 1
+        endif
+    endif
+endif
+
+stop
+
+@enduml
diff --git a/plantuml/history/06_sulfuras.puml b/plantuml/history/06_sulfuras.puml
new file mode 100644
index 00000000..0c7cf0bf
--- /dev/null
+++ b/plantuml/history/06_sulfuras.puml
@@ -0,0 +1,41 @@
+@startuml
+
+start
+note left
+    Do this for each item in the list.
+    An item has a name, a sell in value and a quality value
+end note
+
+if (not "Aged Brie") then (yes)
+    if (quality > 0) then (yes)
+        if (not "Sulfuras, Hand of Ragnaros") then (yes)
+            -lower quality with 1
+        endif
+    endif
+else (no)
+    if (quality < 50) then (yes)
+        -increase quality with 1
+    endif
+endif
+
+if (not "Sulfuras, Hand of Ragnaros") then (yes)
+    -lower sell in with 1
+endif
+
+if (sell in < 0) then (yes)
+    if (not "Aged Brie") then (yes)
+        if (quality > 0) then (yes)
+            if (not "Sulfuras, Hand of Ragnaros") then (yes)
+                -lower quality with 1
+            endif
+        endif
+    else (no)
+        if (quality < 50) then (yes)
+            -increase quality with 1
+        endif
+    endif
+endif
+
+stop
+
+@enduml
diff --git a/plantuml/history/07_backstage-passes.puml b/plantuml/history/07_backstage-passes.puml
new file mode 100644
index 00000000..53a92fd8
--- /dev/null
+++ b/plantuml/history/07_backstage-passes.puml
@@ -0,0 +1,57 @@
+@startuml
+
+start
+note left
+    Do this for each item in the list.
+    An item has a name, a sell in value and a quality value
+end note
+
+if (not "Aged Brie" and not "Backstage passes to a TAFKAL80ETC concert") then (yes)
+    if (quality > 0) then (yes)
+        if (not "Sulfuras, Hand of Ragnaros") then (yes)
+            -lower quality with 1
+        endif
+    endif
+else (no)
+    if (quality < 50) then (yes)
+        -increase quality with 1
+        if ("Backstage passes to a TAFKAL80ETC concert") then (yes)
+            if (sell in < 11) then (yes)
+                if (quality < 50) then (yes)
+                    -increase quality with 1
+                endif
+            endif
+            if (sell in < 6) then (yes)
+                if (quality < 50) then (yes)
+                    -increase quality with 1
+                endif
+            endif
+        endif
+    endif
+endif
+
+if (not "Sulfuras, Hand of Ragnaros") then (yes)
+    -lower sell in with 1
+endif
+
+if (sell in < 0) then (yes)
+    if (not "Aged Brie") then (yes)
+        if (not "Backstage passes to a TAFKAL80ETC concert") then (yes)
+            if (quality > 0) then (yes)
+                if (not "Sulfuras, Hand of Ragnaros") then (yes)
+                    -lower quality with 1
+                endif
+            endif
+        else (no)
+            -lower quality with quality
+        endif
+    else (no)
+        if (quality < 50) then (yes)
+            -increase quality with 1
+        endif
+    endif
+endif
+
+stop
+
+@enduml