Enabled compile-time code evaluation (i.e. "eval" function).

26 files changed, 563 insertions, 557 deletions

diff --git a/lux-bootstrapper/src/lux.clj b/lux-bootstrapper/src/lux.clj
index dc6066669..783a25a64 100644
--- a/lux-bootstrapper/src/lux.clj
+++ b/lux-bootstrapper/src/lux.clj
@@ -7,7 +7,8 @@
             :reload-all)
   (:import (java.io File)))
 
-(def unit-separator (str (char 31)))
+(def unit-separator
+  (str (char 31)))
 
 (defn- separate-paths
   "(-> Text (List Text))"
@@ -20,13 +21,13 @@
 
 (defn -main [& args]
   (|case (&/->list args)
-    (&/$Cons "release" (&/$Cons program-module (&/$Cons dependencies (&/$Cons source-dirs (&/$Cons target-dir (&/$Nil))))))
+    (&/$Item "release" (&/$Item program-module (&/$Item dependencies (&/$Item source-dirs (&/$Item target-dir (&/$End))))))
     (&compiler/compile-program &/$Build program-module
                                (separate-paths dependencies)
                                (separate-paths source-dirs)
                                target-dir)
 
-    (&/$Cons "repl" (&/$Cons dependencies (&/$Cons source-dirs (&/$Cons target-dir (&/$Nil)))))
+    (&/$Item "repl" (&/$Item dependencies (&/$Item source-dirs (&/$Item target-dir (&/$End)))))
     (&repl/repl (separate-paths dependencies)
                 (separate-paths source-dirs)
                 target-dir)
diff --git a/lux-bootstrapper/src/lux/analyser.clj b/lux-bootstrapper/src/lux/analyser.clj
index 4368e1305..ae16eb42c 100644
--- a/lux-bootstrapper/src/lux/analyser.clj
+++ b/lux-bootstrapper/src/lux/analyser.clj
@@ -99,75 +99,75 @@
 
       (&/$Tag ?ident)
       (&/with-analysis-meta location exo-type
-        (analyse-variant+ analyse exo-type ?ident &/$Nil))
+        (analyse-variant+ analyse exo-type ?ident &/$End))
 
       (&/$Identifier ?ident)
       (&/with-analysis-meta location exo-type
         (&&lux/analyse-identifier analyse exo-type ?ident))
 
-      (&/$Form (&/$Cons [command-meta command] parameters))
+      (&/$Form (&/$Item [command-meta command] parameters))
       (|case command
         (&/$Text ?procedure)
         (case ?procedure
           "lux type check"
-          (|let [(&/$Cons ?type
-                          (&/$Cons ?value
-                                   (&/$Nil))) parameters]
+          (|let [(&/$Item ?type
+                          (&/$Item ?value
+                                   (&/$End))) parameters]
             (&/with-analysis-meta location exo-type
               (&&lux/analyse-type-check analyse eval! exo-type ?type ?value)))
 
           "lux type check type"
-          (|let [(&/$Cons ?value (&/$Nil)) parameters]
+          (|let [(&/$Item ?value (&/$End)) parameters]
             (analyse-ast optimize eval! compile-module compilers &type/Type ?value))
 
           "lux type as"
-          (|let [(&/$Cons ?type
-                          (&/$Cons ?value
-                                   (&/$Nil))) parameters]
+          (|let [(&/$Item ?type
+                          (&/$Item ?value
+                                   (&/$End))) parameters]
             (&/with-analysis-meta location exo-type
               (&&lux/analyse-type-as analyse eval! exo-type ?type ?value)))
 
           "lux def"
-          (|let [(&/$Cons [_ (&/$Identifier "" ?name)]
-                          (&/$Cons ?value
-                                   (&/$Cons ?meta
-                                            (&/$Cons exported?
-                                                     (&/$Nil)))
+          (|let [(&/$Item [_ (&/$Identifier "" ?name)]
+                          (&/$Item ?value
+                                   (&/$Item ?meta
+                                            (&/$Item exported?
+                                                     (&/$End)))
                                    )) parameters]
             (&/with-location location
               (&&lux/analyse-def analyse optimize eval! compile-def ?name ?value ?meta exported?)))
 
           "lux def alias"
-          (|let [(&/$Cons [_ (&/$Identifier "" ?alias)]
-                          (&/$Cons [_ (&/$Identifier ?original)]
-                                   (&/$Nil)
+          (|let [(&/$Item [_ (&/$Identifier "" ?alias)]
+                          (&/$Item [_ (&/$Identifier ?original)]
+                                   (&/$End)
                                    )) parameters]
             (&/with-location location
               (&&lux/analyse-def-alias ?alias ?original)))
 
           "lux def type tagged"
-          (|let [(&/$Cons [_ (&/$Identifier "" ?name)]
-                          (&/$Cons ?value
-                                   (&/$Cons ?meta
-                                            (&/$Cons [_ (&/$Tuple ?tags)]
-                                                     (&/$Cons exported?
-                                                              (&/$Nil))))
+          (|let [(&/$Item [_ (&/$Identifier "" ?name)]
+                          (&/$Item ?value
+                                   (&/$Item ?meta
+                                            (&/$Item [_ (&/$Tuple ?tags)]
+                                                     (&/$Item exported?
+                                                              (&/$End))))
                                    )) parameters]
             (&/with-location location
               (&&lux/analyse-def-type-tagged analyse optimize eval! compile-def ?name ?value ?meta ?tags exported?)))
 
           "lux def program"
-          (|let [(&/$Cons ?program (&/$Nil)) parameters]
+          (|let [(&/$Item ?program (&/$End)) parameters]
             (&/with-location location
               (&&lux/analyse-program analyse optimize compile-program ?program)))
 
           "lux def module"
-          (|let [(&/$Cons ?meta (&/$Cons ?imports (&/$Nil))) parameters]
+          (|let [(&/$Item ?meta (&/$Item ?imports (&/$End))) parameters]
             (&/with-location location
               (&&lux/analyse-module analyse optimize eval! compile-module ?meta ?imports)))
 
           "lux in-module"
-          (|let [(&/$Cons [_ (&/$Text ?module)] (&/$Cons ?expr (&/$Nil))) parameters]
+          (|let [(&/$Item [_ (&/$Text ?module)] (&/$Item ?expr (&/$End))) parameters]
             (&/with-location location
               (&/with-module ?module
                 (analyse exo-type ?expr))))
@@ -182,7 +182,7 @@
                   (&&common/analyse-proc analyse exo-type ?procedure parameters))))
         
         (&/$Nat idx)
-        (|let [(&/$Cons [_ (&/$Bit ?right)] parameters*) parameters]
+        (|let [(&/$Item [_ (&/$Bit ?right)] parameters*) parameters]
           (&/with-analysis-meta location exo-type
             (&&lux/analyse-variant analyse (&/$Right exo-type) (if ?right (inc idx) idx) ?right parameters*)))
 
@@ -192,14 +192,14 @@
 
         ;; Pattern-matching syntax.
         (&/$Record ?pattern-matching)
-        (|let [(&/$Cons ?input (&/$Nil)) parameters]
+        (|let [(&/$Item ?input (&/$End)) parameters]
           (&/with-analysis-meta location exo-type
             (&&lux/analyse-case analyse exo-type ?input ?pattern-matching)))
 
         ;; Function syntax.
-        (&/$Tuple (&/$Cons [_ (&/$Identifier "" ?self)]
-                           (&/$Cons [_ (&/$Identifier "" ?arg)] (&/$Nil))))
-        (|let [(&/$Cons ?body (&/$Nil)) parameters]
+        (&/$Tuple (&/$Item [_ (&/$Identifier "" ?self)]
+                           (&/$Item [_ (&/$Identifier "" ?arg)] (&/$End))))
+        (|let [(&/$Item ?body (&/$End)) parameters]
           (&/with-analysis-meta location exo-type
             (&&lux/analyse-function analyse exo-type ?self ?arg ?body)))
 
diff --git a/lux-bootstrapper/src/lux/analyser/base.clj b/lux-bootstrapper/src/lux/analyser/base.clj
index e5f47f977..1a61bcfa5 100644
--- a/lux-bootstrapper/src/lux/analyser/base.clj
+++ b/lux-bootstrapper/src/lux/analyser/base.clj
@@ -52,7 +52,7 @@
 (defn cap-1 [action]
   (|do [result action]
     (|case result
-      (&/$Cons x (&/$Nil))
+      (&/$Item x (&/$End))
       (return x)
 
       _
diff --git a/lux-bootstrapper/src/lux/analyser/case.clj b/lux-bootstrapper/src/lux/analyser/case.clj
index d059ce189..ba8afd4e8 100644
--- a/lux-bootstrapper/src/lux/analyser/case.clj
+++ b/lux-bootstrapper/src/lux/analyser/case.clj
@@ -35,7 +35,7 @@
 
 ;; [Utils]
 (def ^:private unit-tuple
-  (&/T [(&/T ["" -1 -1]) (&/$Tuple &/$Nil)]))
+  (&/T [(&/T ["" -1 -1]) (&/$Tuple &/$End)]))
 
 (defn ^:private resolve-type [type]
   (if (&type/type= &type/Any type)
@@ -121,7 +121,7 @@
     
     (&/$UnivQ ?local-env ?local-def)
     (|case ?local-env
-      (&/$Nil)
+      (&/$End)
       (&/$UnivQ ?local-env (beta-reduce! (inc level) env ?local-def))
 
       _
@@ -129,7 +129,7 @@
 
     (&/$ExQ ?local-env ?local-def)
     (|case ?local-env
-      (&/$Nil)
+      (&/$End)
       (&/$ExQ ?local-env (beta-reduce! (inc level) env ?local-def))
 
       _
@@ -155,14 +155,14 @@
   (|case type-fn
     (&/$UnivQ local-env local-def)
     (return (beta-reduce! 0 (->> local-env
-                                 (&/$Cons param)
-                                 (&/$Cons type-fn))
+                                 (&/$Item param)
+                                 (&/$Item type-fn))
                           local-def))
 
     (&/$ExQ local-env local-def)
     (return (beta-reduce! 0 (->> local-env
-                                 (&/$Cons param)
-                                 (&/$Cons type-fn))
+                                 (&/$Item param)
+                                 (&/$Item type-fn))
                           local-def))
 
     (&/$Apply A F)
@@ -189,7 +189,7 @@
     (&type/with-var
       (fn [$var]
         (|do [=type (apply-type! type $var)
-              ==type (adjust-type* (&/$Cons (&/T [_aenv 1 $var])
+              ==type (adjust-type* (&/$Item (&/T [_aenv 1 $var])
                                             (&/|map update-up-frame up))
                                    =type)]
           (&type/clean $var ==type))))
@@ -247,7 +247,7 @@
 
 (defn adjust-type [type]
   "(-> Type (Lux Type))"
-  (adjust-type* &/$Nil type))
+  (adjust-type* &/$End type))
 
 (defn ^:private analyse-pattern [var?? value-type pattern kont]
   (|let [[meta pattern*] pattern]
@@ -300,12 +300,12 @@
 
       (&/$Tuple ?members)
       (|case ?members
-        (&/$Nil)
+        (&/$End)
         (|do [_ (&type/check value-type &type/Any)
               =kont kont]
           (return (&/T [($TupleTestAC (&/|list)) =kont])))
 
-        (&/$Cons ?member (&/$Nil))
+        (&/$Item ?member (&/$End))
         (analyse-pattern var?? value-type ?member kont)
 
         _
@@ -322,9 +322,9 @@
                 (|do [[=tests =kont] (&/fold (fn [kont* vm]
                                                (|let [[v m] vm]
                                                  (|do [[=test [=tests =kont]] (analyse-pattern &/$None v m kont*)]
-                                                   (return (&/T [(&/$Cons =test =tests) =kont])))))
+                                                   (return (&/T [(&/$Item =test =tests) =kont])))))
                                              (|do [=kont kont]
-                                               (return (&/T [&/$Nil =kont])))
+                                               (return (&/T [&/$End =kont])))
                                              (&/|reverse (&/zip2 _tuple-types ?members)))]
                   (return (&/T [($TupleTestAC =tests) =kont])))
                 (&/fail-with-loc (str "[Pattern-matching Error] Pattern-matching mismatch. Requires tuple[" (&/|length (&type/flatten-prod value-type*)) "]. Given tuple [" (&/|length ?members) "].\n"
@@ -360,7 +360,7 @@
             [=test =kont] (analyse-pattern &/$None case-type unit-tuple kont)]
         (return (&/T [($VariantTestAC (&/T [idx (&/|length group) =test])) =kont])))
 
-      (&/$Form (&/$Cons [_ (&/$Nat idx)] (&/$Cons [_ (&/$Bit right?)] ?values)))
+      (&/$Form (&/$Item [_ (&/$Nat idx)] (&/$Item [_ (&/$Bit right?)] ?values)))
       (let [idx (if right? (inc idx) idx)]
         (|do [value-type* (adjust-type value-type)
               case-type (&type/sum-at idx value-type*)
@@ -371,7 +371,7 @@
                               (analyse-pattern &/$None case-type (&/T [(&/T ["" -1 -1]) (&/$Tuple ?values)]) kont))]
           (return (&/T [($VariantTestAC (&/T [idx (&/|length (&type/flatten-sum value-type*)) =test])) =kont]))))
 
-      (&/$Form (&/$Cons [_ (&/$Tag ?ident)] ?values))
+      (&/$Form (&/$Item [_ (&/$Tag ?ident)] ?values))
       (|do [[=module =name] (&&/resolved-ident ?ident)
             must-infer? (&type/unknown? value-type)
             variant-type (if must-infer?
@@ -398,7 +398,7 @@
 (defn ^:private analyse-branch [analyse exo-type var?? value-type pattern body patterns]
   (|do [pattern+body (analyse-pattern var?? value-type pattern
                                       (&&/analyse-1 analyse exo-type body))]
-    (return (&/$Cons pattern+body patterns))))
+    (return (&/$Item pattern+body patterns))))
 
 (defn ^:private merge-total [struct test+body]
   (|let [[test ?body] test+body]
@@ -461,37 +461,37 @@
       (return ($BitTotal total? (&/|list ?value)))
 
       [($BitTotal total? ?values) ($BitTestAC ?value)]
-      (return ($BitTotal total? (&/$Cons ?value ?values)))
+      (return ($BitTotal total? (&/$Item ?value ?values)))
 
       [($DefaultTotal total?) ($NatTestAC ?value)]
       (return ($NatTotal total? (&/|list ?value)))
 
       [($NatTotal total? ?values) ($NatTestAC ?value)]
-      (return ($NatTotal total? (&/$Cons ?value ?values)))
+      (return ($NatTotal total? (&/$Item ?value ?values)))
 
       [($DefaultTotal total?) ($IntTestAC ?value)]
       (return ($IntTotal total? (&/|list ?value)))
 
       [($IntTotal total? ?values) ($IntTestAC ?value)]
-      (return ($IntTotal total? (&/$Cons ?value ?values)))
+      (return ($IntTotal total? (&/$Item ?value ?values)))
 
       [($DefaultTotal total?) ($RevTestAC ?value)]
       (return ($RevTotal total? (&/|list ?value)))
 
       [($RevTotal total? ?values) ($RevTestAC ?value)]
-      (return ($RevTotal total? (&/$Cons ?value ?values)))
+      (return ($RevTotal total? (&/$Item ?value ?values)))
 
       [($DefaultTotal total?) ($FracTestAC ?value)]
       (return ($FracTotal total? (&/|list ?value)))
 
       [($FracTotal total? ?values) ($FracTestAC ?value)]
-      (return ($FracTotal total? (&/$Cons ?value ?values)))
+      (return ($FracTotal total? (&/$Item ?value ?values)))
 
       [($DefaultTotal total?) ($TextTestAC ?value)]
       (return ($TextTotal total? (&/|list ?value)))
 
       [($TextTotal total? ?values) ($TextTestAC ?value)]
-      (return ($TextTotal total? (&/$Cons ?value ?values)))
+      (return ($TextTotal total? (&/$Item ?value ?values)))
 
       [($DefaultTotal total?) ($TupleTestAC ?tests)]
       (|do [structs (&/map% (fn [t]
@@ -578,7 +578,7 @@
 
     ($TupleTotal ?total ?structs)
     (|case ?structs
-      (&/$Nil)
+      (&/$End)
       (|do [value-type* (resolve-type value-type)]
         (if (&type/type= &type/Any value-type*)
           (return true)
@@ -589,7 +589,7 @@
         (if unknown?
           (|do [=structs (&/map% (check-totality+ check-totality) ?structs)
                 _ (&type/check value-type (|case (->> (&/|map &/|second =structs) (&/|reverse))
-                                            (&/$Cons last prevs)
+                                            (&/$Item last prevs)
                                             (&/fold (fn [right left] (&/$Product left right))
                                                     last prevs)))]
             (return (or ?total
@@ -629,7 +629,7 @@
   (|do [patterns (&/fold% (fn [patterns branch]
                             (|let [[pattern body] branch]
                               (analyse-branch analyse exo-type var?? value-type pattern body patterns)))
-                          &/$Nil
+                          &/$End
                           branches)
         struct (&/fold% merge-total ($DefaultTotal false) patterns)
         ? (check-totality value-type struct)
diff --git a/lux-bootstrapper/src/lux/analyser/env.clj b/lux-bootstrapper/src/lux/analyser/env.clj
index a2b6e5ad3..c170771ea 100644
--- a/lux-bootstrapper/src/lux/analyser/env.clj
+++ b/lux-bootstrapper/src/lux/analyser/env.clj
@@ -15,7 +15,7 @@
           =return (body (&/update$ &/$scopes
                                    (fn [stack]
                                      (let [var-analysis (&&/|meta type &/empty-location (&&/$var (&/$Local (->> (&/|head stack) (&/get$ &/$locals) (&/get$ &/$counter)))))]
-                                       (&/$Cons (&/update$ &/$locals #(->> %
+                                       (&/$Item (&/update$ &/$locals #(->> %
                                                                            (&/update$ &/$counter inc)
                                                                            (&/update$ &/$mappings (fn [m] (&/|put name (&/T [type var-analysis]) m))))
                                                            (&/|head stack))
@@ -24,7 +24,7 @@
       (|case =return
         (&/$Right ?state ?value)
         (return* (&/update$ &/$scopes (fn [stack*]
-                                        (&/$Cons (&/update$ &/$locals #(->> %
+                                        (&/$Item (&/update$ &/$locals #(->> %
                                                                             (&/update$ &/$counter dec)
                                                                             (&/set$ &/$mappings old-mappings))
                                                             (&/|head stack*))
@@ -40,7 +40,7 @@
     (let [old-mappings (->> state (&/get$ &/$scopes) &/|head (&/get$ &/$locals) (&/get$ &/$mappings))
           =return (body (&/update$ &/$scopes
                                    (fn [stack]
-                                     (&/$Cons (&/update$ &/$locals #(->> %
+                                     (&/$Item (&/update$ &/$locals #(->> %
                                                                          (&/update$ &/$mappings (fn [m] (&/|put name
                                                                                                                 (&/T [(&&/expr-type* var-analysis)
                                                                                                                       var-analysis])
@@ -51,7 +51,7 @@
       (|case =return
         (&/$Right ?state ?value)
         (return* (&/update$ &/$scopes (fn [stack*]
-                                        (&/$Cons (&/update$ &/$locals #(->> %
+                                        (&/$Item (&/update$ &/$locals #(->> %
                                                                             (&/set$ &/$mappings old-mappings))
                                                             (&/|head stack*))
                                                  (&/|tail stack*)))
@@ -64,11 +64,11 @@
 (def captured-vars
   (fn [state]
     (|case (&/get$ &/$scopes state)
-      (&/$Nil)
+      (&/$End)
       ((&/fail-with-loc "[Analyser Error] Cannot obtain captured vars without environments.")
        state)
 
-      (&/$Cons env _)
+      (&/$Item env _)
       (return* state (->> env
                           (&/get$ &/$captured)
                           (&/get$ &/$mappings)
diff --git a/lux-bootstrapper/src/lux/analyser/lux.clj b/lux-bootstrapper/src/lux/analyser/lux.clj
index e71e54f4f..857f65e00 100644
--- a/lux-bootstrapper/src/lux/analyser/lux.clj
+++ b/lux-bootstrapper/src/lux/analyser/lux.clj
@@ -53,12 +53,12 @@
 
 (defn analyse-tuple [analyse ?exo-type ?elems]
   (|case ?elems
-    (&/$Nil)
+    (&/$End)
     (analyse-unit analyse (|case ?exo-type
                             (&/$Left exo-type) exo-type
                             (&/$Right exo-type) exo-type))
 
-    (&/$Cons ?elem (&/$Nil))
+    (&/$Item ?elem (&/$End))
     (analyse (|case ?exo-type
                (&/$Left exo-type) exo-type
                (&/$Right exo-type) exo-type)
@@ -80,7 +80,7 @@
                                     (|do [:let [=var* (next-parameter-type tuple-type)]
                                           _ (&type/set-var iid =var*)
                                           tuple-type* (&type/clean $var tuple-type)]
-                                      (return (&/$UnivQ &/$Nil tuple-type*)))
+                                      (return (&/$UnivQ &/$End tuple-type*)))
 
                                     _
                                     (&type/clean $var tuple-type))]
@@ -97,7 +97,7 @@
                                   (return =analysis))
                                ?elems)
                 _ (&type/check exo-type (|case (->> (&/|map &&/expr-type* =elems) (&/|reverse))
-                                          (&/$Cons last prevs)
+                                          (&/$Item last prevs)
                                           (&/fold (fn [right left] (&/$Product left right))
                                                   last prevs)))
                 _location &/location]
@@ -158,16 +158,16 @@
 (defn ^:private analyse-variant-body [analyse exo-type ?values]
   (|do [_location &/location
         output (|case ?values
-                 (&/$Nil)
+                 (&/$End)
                  (analyse-unit analyse exo-type)
 
-                 (&/$Cons ?value (&/$Nil))
+                 (&/$Item ?value (&/$End))
                  (analyse exo-type ?value)
 
                  _
                  (analyse-tuple analyse (&/$Right exo-type) ?values))]
     (|case output
-      (&/$Cons x (&/$Nil))
+      (&/$Item x (&/$End))
       (return x)
 
       _
@@ -189,7 +189,7 @@
                                   (|do [:let [=var* (next-parameter-type variant-type)]
                                         _ (&type/set-var iid =var*)
                                         variant-type* (&type/clean $var variant-type)]
-                                    (return (&/$UnivQ &/$Nil variant-type*)))
+                                    (return (&/$UnivQ &/$End variant-type*)))
 
                                   _
                                   (&type/clean $var variant-type))]
@@ -278,20 +278,20 @@
                              (->> % (&/get$ &/$captured) (&/get$ &/$mappings) (&/|contains? name) not))
            [inner outer] (&/|split-with no-binding? stack)]
       (|case outer
-        (&/$Nil)
+        (&/$End)
         (&/run-state (|do [module-name &/get-module-name]
                        (analyse-global analyse exo-type module-name name))
                      state)
 
-        (&/$Cons bottom-outer _)
+        (&/$Item bottom-outer _)
         (|let [scopes (&/|map #(&/get$ &/$name %) (&/|reverse inner))
                [=local inner*] (&/fold2 (fn [register+new-inner frame in-scope]
                                           (|let [[register new-inner] register+new-inner
                                                  [register* frame*] (&&function/close-over in-scope name register frame)]
-                                            (&/T [register* (&/$Cons frame* new-inner)])))
+                                            (&/T [register* (&/$Item frame* new-inner)])))
                                         (&/T [(&/|second (or (->> bottom-outer (&/get$ &/$locals)  (&/get$ &/$mappings) (&/|get name))
                                                              (->> bottom-outer (&/get$ &/$captured) (&/get$ &/$mappings) (&/|get name))))
-                                              &/$Nil])
+                                              &/$End])
                                         (&/|reverse inner) scopes)]
           ((|do [_ (&type/check exo-type (&&/expr-type* =local))]
              (return (&/|list =local)))
@@ -307,11 +307,11 @@
 
 (defn ^:private analyse-apply* [analyse exo-type fun-type ?args]
   (|case ?args
-    (&/$Nil)
+    (&/$End)
     (|do [_ (&type/check exo-type fun-type)]
-      (return (&/T [fun-type &/$Nil])))
+      (return (&/T [fun-type &/$End])))
     
-    (&/$Cons ?arg ?args*)
+    (&/$Item ?arg ?args*)
     (|do [?fun-type* (&type/actual-type fun-type)]
       (&/with-attempt
         (|case ?fun-type*
@@ -328,7 +328,7 @@
                                    (&type/clean $var =output-t)
                                  (|do [_ (&type/set-var ?id (next-parameter-type =output-t))
                                        cleaned-output* (&type/clean $var =output-t)
-                                       :let [cleaned-output (&/$UnivQ &/$Nil cleaned-output*)]]
+                                       :let [cleaned-output (&/$UnivQ &/$End cleaned-output*)]]
                                    (return cleaned-output)))
                         _ (&type/clean $var exo-type)]
                     (return (&/T [type** ==args])))
@@ -358,7 +358,7 @@
                        (&&/analyse-1 analyse ?input-t ?arg)
                        (fn [err]
                          (&/fail-with-loc (str err "\n" "[Analyser Error] Argument expected: " (&type/show-type ?input-t)))))]
-            (return (&/T [=output-t (&/$Cons =arg =args)])))
+            (return (&/T [=output-t (&/$Item =arg =args)])))
 
           _
           (&/fail-with-loc (str "[Analyser Error] Cannot apply a non-function: " (&type/show-type ?fun-type*))))
@@ -418,7 +418,7 @@
 (defn ^:private unravel-inf-appt [type]
   (|case type
     (&/$Apply (&/$Var _inf-var) =input+)
-    (&/$Cons _inf-var (unravel-inf-appt =input+))
+    (&/$Item _inf-var (unravel-inf-appt =input+))
 
     _
     (&/|list)))
@@ -430,7 +430,7 @@
           _ (&type/set-var iid =input*)
           =func* (&type/clean $input =func)
           =func** (&type/clean $output =func*)]
-      (return (&/$UnivQ &/$Nil =func**)))
+      (return (&/$UnivQ &/$End =func**)))
     
     (&/$Apply (&/$Var _inf-var) =input+)
     (&/fold% (fn [_func _inf-var]
@@ -547,7 +547,7 @@
                               (if (= wanted-name source-name)
                                 ""
                                 (str "\nThis is an alias for " source-name)))))
-      (return &/$Nil))))
+      (return &/$End))))
 
 (defn analyse-def* [analyse optimize eval! compile-def ?name ?value ?meta exported? & [?expected-type]]
   (|do [_ &/ensure-directive
@@ -572,7 +572,7 @@
 
 (defn analyse-def [analyse optimize eval! compile-def ?name ?value ?meta exported?]
   (|do [_ (analyse-def* analyse optimize eval! compile-def ?name ?value ?meta exported?)]
-    (return &/$Nil)))
+    (return &/$End)))
 
 (defn analyse-def-type-tagged [analyse optimize eval! compile-def ?name ?value ?meta tags* exported?]
   (|do [[module-name def-type def-value =exported?] (analyse-def* analyse optimize eval! compile-def ?name ?value ?meta exported? &type/Type)
@@ -587,7 +587,7 @@
                          (&/fail-with-loc "[Analyser Error] Incorrect format for tags.")))
                      tags*)
         _ (&&module/declare-tags module-name tags =exported? def-value)]
-    (return &/$Nil)))
+    (return &/$End)))
 
 (defn analyse-def-alias [?alias ?original]
   (|let [[r-module r-name] ?original]
@@ -596,7 +596,7 @@
           _ (&&module/find-def r-module r-name)
           _ (&/without-repl-closure
              (&&module/define-alias module-name ?alias ?original))]
-      (return &/$Nil))))
+      (return &/$End))))
 
 (defn ^:private merge-module-states
   "(-> Host Host Host)"
@@ -696,7 +696,7 @@
                        (&/fail ?error)))
                    _compiler
                    =asyncs)]
-    (return &/$Nil)))
+    (return &/$End)))
 
 (defn ^:private coerce
   "(-> Type Analysis Analysis)"
@@ -728,4 +728,4 @@
     (|do [_ &/ensure-directive
           =program (&&/analyse-1 analyse program-type ?program)
           _ (compile-program (optimize =program))]
-      (return &/$Nil))))
+      (return &/$End))))
diff --git a/lux-bootstrapper/src/lux/analyser/module.clj b/lux-bootstrapper/src/lux/analyser/module.clj
index d41eb73d5..12e6b816a 100644
--- a/lux-bootstrapper/src/lux/analyser/module.clj
+++ b/lux-bootstrapper/src/lux/analyser/module.clj
@@ -35,7 +35,7 @@
         ;; "lux;defs"
         (&/|table)
         ;; "lux;imports"
-        &/$Nil
+        &/$End
         ;; "lux;tags"
         (&/|table)
         ;; "lux;types"
@@ -87,7 +87,7 @@
         (return* (&/update$ &/$modules
                             (fn [ms]
                               (&/|update current-module
-                                         (fn [m] (&/update$ $imports (partial &/$Cons module) m))
+                                         (fn [m] (&/update$ $imports (partial &/$Item module) m))
                                          ms))
                             state)
                  nil)))))
@@ -108,7 +108,7 @@
 (defn define-alias [module name de-aliased]
   (fn [state]
     (|case (&/get$ &/$scopes state)
-      (&/$Cons ?env (&/$Nil))
+      (&/$Item ?env (&/$End))
       (return* (->> state
                     (&/update$ &/$modules
                                (fn [ms]
@@ -127,7 +127,7 @@
 (defn define [module name exported? def-type def-meta def-value]
   (fn [state]
     (|case (&/get$ &/$scopes state)
-      (&/$Cons ?env (&/$Nil))
+      (&/$Item ?env (&/$End))
       (return* (->> state
                     (&/update$ &/$modules
                                (fn [ms]
@@ -287,7 +287,7 @@
   (fn [state]
     (return* (->> state
                   (&/update$ &/$modules #(&/|put name (new-module hash) %))
-                  (&/set$ &/$scopes (&/|list (&/env name &/$Nil)))
+                  (&/set$ &/$scopes (&/|list (&/env name &/$End)))
                   (&/set$ &/$current-module (&/$Some name)))
              nil)))
 
@@ -406,9 +406,9 @@
     [_ (&/$Tuple _parts)]
     (&/map% (fn [_part]
               (|case _part
-                [_ (&/$Tuple (&/$Cons [[_ (&/$Text _module)]
-                                       (&/$Cons [[_ (&/$Text _alias)]
-                                                 (&/$Nil)])]))]
+                [_ (&/$Tuple (&/$Item [[_ (&/$Text _module)]
+                                       (&/$Item [[_ (&/$Text _alias)]
+                                                 (&/$End)])]))]
                 (return (&/T [_module _alias]))
 
                 _
diff --git a/lux-bootstrapper/src/lux/analyser/parser.clj b/lux-bootstrapper/src/lux/analyser/parser.clj
index 15224573c..cfc26ea2a 100644
--- a/lux-bootstrapper/src/lux/analyser/parser.clj
+++ b/lux-bootstrapper/src/lux/analyser/parser.clj
@@ -20,23 +20,23 @@
   (fn [state]
     (|case (action state)
       (&/$Left ^String error)
-      (&/$Right (&/T [state &/$Nil]))
+      (&/$Right (&/T [state &/$End]))
 
       (&/$Right state* head)
       ((|do [tail (repeat% action)]
-         (return (&/$Cons head tail)))
+         (return (&/$Item head tail)))
        state*))))
 
 (defn ^:private spaced [action]
   (fn [state]
     (|case (action state)
       (&/$Left ^String error)
-      (&/$Right (&/T [state &/$Nil]))
+      (&/$Right (&/T [state &/$End]))
 
       (&/$Right state* head)
       ((&/try-all% (&/|list (|do [_ _space_
                                   tail (spaced action)]
-                              (return (&/$Cons head tail)))
+                              (return (&/$Item head tail)))
                             (return (&/|list head))))
        state*))))
 
@@ -129,7 +129,7 @@
 (def ^:private parse-ctor-arg
   (with-brackets
     (|do [=class parse-gclass
-          (&/$Cons =term (&/$Nil)) (with-pre-space
+          (&/$Item =term (&/$End)) (with-pre-space
                                      &parser/parse)]
       (return (&/T [=class =term])))))
 
@@ -181,7 +181,7 @@
       (|do [[_ _ ?] (&reader/read-text? " ")]
         (if ?
           (|do [=tail parse-gvars]
-            (return (&/$Cons =head =tail)))
+            (return (&/$Item =head =tail)))
           (return (&/|list =head))))
 
       (&/$None)
@@ -264,7 +264,7 @@
         =ctor-args (with-pre-space
                      (with-brackets
                        (spaced parse-ctor-arg)))
-        (&/$Cons =body (&/$Nil)) (with-pre-space
+        (&/$Item =body (&/$End)) (with-pre-space
                                    &parser/parse)]
     (return (&/$ConstructorMethodSyntax (&/T [=privacy-modifier =strict =anns =gvars =exceptions =inputs =ctor-args =body])))))
 
@@ -294,7 +294,7 @@
                     (spaced parse-arg-decl)))
         =output (with-pre-space
                   parse-gclass)
-        (&/$Cons =body (&/$Nil)) (with-pre-space
+        (&/$Item =body (&/$End)) (with-pre-space
                                    &parser/parse)]
     (return (&/$VirtualMethodSyntax (&/T [=name =privacy-modifier =final? =strict =anns =gvars =exceptions =inputs =output =body])))))
 
@@ -321,7 +321,7 @@
                     (spaced parse-arg-decl)))
         =output (with-pre-space
                   parse-gclass)
-        (&/$Cons =body (&/$Nil)) (with-pre-space
+        (&/$Item =body (&/$End)) (with-pre-space
                                    &parser/parse)]
     (return (&/$OverridenMethodSyntax (&/T [=class-decl =name =strict =anns =gvars =exceptions =inputs =output =body])))))
 
@@ -348,7 +348,7 @@
                     (spaced parse-arg-decl)))
         =output (with-pre-space
                   parse-gclass)
-        (&/$Cons =body (&/$Nil)) (with-pre-space
+        (&/$Item =body (&/$End)) (with-pre-space
                                    &parser/parse)]
     (return (&/$StaticMethodSyntax (&/T [=name =privacy-modifier =strict =anns =gvars =exceptions =inputs =output =body])))))
 
@@ -416,7 +416,7 @@
                                          (spaced parse-ann)))
                                =type (with-pre-space
                                        parse-gclass)
-                               (&/$Cons =value (&/$Nil)) (with-pre-space
+                               (&/$Item =value (&/$End)) (with-pre-space
                                                            &parser/parse)]
                            (return (&/$ConstantFieldSyntax =name =anns =type =value)))
 
diff --git a/lux-bootstrapper/src/lux/analyser/proc/common.clj b/lux-bootstrapper/src/lux/analyser/proc/common.clj
index 439ad0d10..2d4c0d27e 100644
--- a/lux-bootstrapper/src/lux/analyser/proc/common.clj
+++ b/lux-bootstrapper/src/lux/analyser/proc/common.clj
@@ -10,7 +10,7 @@
 (defn- analyse-lux-is [analyse exo-type ?values]
   (&type/with-var
     (fn [$var]
-      (|do [:let [(&/$Cons reference (&/$Cons sample (&/$Nil))) ?values]
+      (|do [:let [(&/$Item reference (&/$Item sample (&/$End))) ?values]
             =reference (&&/analyse-1 analyse $var reference)
             =sample (&&/analyse-1 analyse $var sample)
             _ (&type/check exo-type &type/Bit)
@@ -21,7 +21,7 @@
 (defn- analyse-lux-try [analyse exo-type ?values]
   (&type/with-var
     (fn [$var]
-      (|do [:let [(&/$Cons op (&/$Nil)) ?values]
+      (|do [:let [(&/$Item op (&/$End)) ?values]
             =op (&&/analyse-1 analyse (&/$Function &type/Any $var) op)
             _ (&type/check exo-type (&/$Sum &type/Text ;; lux.Left
                                             $var ;; lux.Right
@@ -31,7 +31,7 @@
                                    (&&/$proc (&/T ["lux" "try"]) (&/|list =op) (&/|list)))))))))
 
 (defn- analyse-lux-macro [analyse exo-type ?values]
-  (|do [:let [(&/$Cons macro (&/$Nil)) ?values]
+  (|do [:let [(&/$Item macro (&/$End)) ?values]
         [_real-name [_exported? _def-type _meta macro-type]] (&&module/find-def! &/prelude "Macro'")
         [[=macro*-type =location] =macro] (&&/analyse-1 analyse macro-type macro)
         _ (&type/check exo-type &type/Macro)]
@@ -40,7 +40,7 @@
 
 (do-template [<name> <proc> <input-type> <output-type>]
   (defn- <name> [analyse exo-type ?values]
-    (|do [:let [(&/$Cons reference (&/$Cons sample (&/$Nil))) ?values]
+    (|do [:let [(&/$Item reference (&/$Item sample (&/$End))) ?values]
           =reference (&&/analyse-1 analyse <input-type> reference)
           =sample (&&/analyse-1 analyse <input-type> sample)
           _ (&type/check exo-type <output-type>)
@@ -53,7 +53,7 @@
   )
 
 (defn- analyse-text-concat [analyse exo-type ?values]
-  (|do [:let [(&/$Cons parameter (&/$Cons subject (&/$Nil))) ?values]
+  (|do [:let [(&/$Item parameter (&/$Item subject (&/$End))) ?values]
         =parameter (&&/analyse-1 analyse &type/Text parameter)
         =subject (&&/analyse-1 analyse &type/Text subject)
         _ (&type/check exo-type &type/Text)
@@ -62,7 +62,7 @@
                                (&&/$proc (&/T ["text" "concat"]) (&/|list =parameter =subject) (&/|list)))))))
 
 (defn- analyse-text-index [analyse exo-type ?values]
-  (|do [:let [(&/$Cons start (&/$Cons part (&/$Cons text (&/$Nil)))) ?values]
+  (|do [:let [(&/$Item start (&/$Item part (&/$Item text (&/$End)))) ?values]
         =start (&&/analyse-1 analyse &type/Nat start)
         =part (&&/analyse-1 analyse &type/Text part)
         =text (&&/analyse-1 analyse &type/Text text)
@@ -74,7 +74,7 @@
                                          (&/|list)))))))
 
 (defn- analyse-text-clip [analyse exo-type ?values]
-  (|do [:let [(&/$Cons from (&/$Cons to (&/$Cons text (&/$Nil)))) ?values]
+  (|do [:let [(&/$Item from (&/$Item to (&/$Item text (&/$End)))) ?values]
         =from (&&/analyse-1 analyse &type/Nat from)
         =to (&&/analyse-1 analyse &type/Nat to)
         =text (&&/analyse-1 analyse &type/Text text)
@@ -87,7 +87,7 @@
 
 (do-template [<name> <proc>]
   (defn- <name> [analyse exo-type ?values]
-    (|do [:let [(&/$Cons text (&/$Nil)) ?values]
+    (|do [:let [(&/$Item text (&/$End)) ?values]
           =text (&&/analyse-1 analyse &type/Text text)
           _ (&type/check exo-type &type/Nat)
           _location &/location]
@@ -100,7 +100,7 @@
   )
 
 (defn- analyse-text-char [analyse exo-type ?values]
-  (|do [:let [(&/$Cons idx (&/$Cons text (&/$Nil))) ?values]
+  (|do [:let [(&/$Item idx (&/$Item text (&/$End))) ?values]
         =idx (&&/analyse-1 analyse &type/Nat idx)
         =text (&&/analyse-1 analyse &type/Text text)
         _ (&type/check exo-type &type/Nat)
@@ -114,7 +114,7 @@
   (let [inputT (&/$Apply &type/Any &type/I64)
         outputT &type/I64]
     (defn- <name> [analyse exo-type ?values]
-      (|do [:let [(&/$Cons mask (&/$Cons input (&/$Nil))) ?values]
+      (|do [:let [(&/$Item mask (&/$Item input (&/$End))) ?values]
             =mask (&&/analyse-1 analyse inputT mask)
             =input (&&/analyse-1 analyse inputT input)
             _ (&type/check exo-type outputT)
@@ -131,7 +131,7 @@
   (let [inputT (&/$Apply &type/Any &type/I64)
         outputT &type/I64]
     (defn- <name> [analyse exo-type ?values]
-      (|do [:let [(&/$Cons shift (&/$Cons input (&/$Nil))) ?values]
+      (|do [:let [(&/$Item shift (&/$Item input (&/$End))) ?values]
             =shift (&&/analyse-1 analyse &type/Nat shift)
             =input (&&/analyse-1 analyse inputT input)
             _ (&type/check exo-type outputT)
@@ -147,7 +147,7 @@
   (let [inputT <input-type>
         outputT <output-type>]
     (defn- <name> [analyse exo-type ?values]
-      (|do [:let [(&/$Cons parameterC (&/$Cons subjectC (&/$Nil))) ?values]
+      (|do [:let [(&/$Item parameterC (&/$Item subjectC (&/$End))) ?values]
             parameterA (&&/analyse-1 analyse <input-type> parameterC)
             subjectA (&&/analyse-1 analyse <input-type> subjectC)
             _ (&type/check exo-type <output-type>)
@@ -175,7 +175,7 @@
 
 (do-template [<encode> <encode-op> <decode> <decode-op> <type>]
   (do (defn- <encode> [analyse exo-type ?values]
-        (|do [:let [(&/$Cons x (&/$Nil)) ?values]
+        (|do [:let [(&/$Item x (&/$End)) ?values]
               =x (&&/analyse-1 analyse <type> x)
               _ (&type/check exo-type &type/Text)
               _location &/location]
@@ -184,7 +184,7 @@
 
     (let [decode-type (&/$Apply <type> &type/Maybe)]
       (defn- <decode> [analyse exo-type ?values]
-        (|do [:let [(&/$Cons x (&/$Nil)) ?values]
+        (|do [:let [(&/$Item x (&/$End)) ?values]
               =x (&&/analyse-1 analyse &type/Text x)
               _ (&type/check exo-type decode-type)
               _location &/location]
@@ -196,7 +196,7 @@
 
 (do-template [<name> <from-type> <to-type> <op>]
   (defn- <name> [analyse exo-type ?values]
-    (|do [:let [(&/$Cons x (&/$Nil)) ?values]
+    (|do [:let [(&/$Item x (&/$End)) ?values]
           =x (&&/analyse-1 analyse <from-type> x)
           _ (&type/check exo-type <to-type>)
           _location &/location]
@@ -212,14 +212,14 @@
   )
 
 (defn- analyse-io-current-time [analyse exo-type ?values]
-  (|do [:let [(&/$Nil) ?values]
+  (|do [:let [(&/$End) ?values]
         _ (&type/check exo-type &type/Int)
         _location &/location]
     (return (&/|list (&&/|meta exo-type _location
                                (&&/$proc (&/T ["io" "current-time"]) (&/|list) (&/|list)))))))
 
 (defn- analyse-syntax-char-case! [analyse exo-type ?values]
-  (|do [:let [(&/$Cons ?input (&/$Cons [_ (&/$Tuple ?pairs)] (&/$Cons ?else (&/$Nil)))) ?values]
+  (|do [:let [(&/$Item ?input (&/$Item [_ (&/$Tuple ?pairs)] (&/$Item ?else (&/$End)))) ?values]
         _location &/location
         =input (&&/analyse-1 analyse &type/Nat ?input)
         _ (assert! (even? (&/|length ?pairs)) "The number of matches must be even!")
@@ -235,7 +235,7 @@
         =else (&&/analyse-1 analyse exo-type ?else)]
     (return (&/|list (&&/|meta exo-type _location
                                (&&/$proc (&/T ["lux" "syntax char case!"])
-                                         (&/$Cons =input (&/$Cons =else (&/|map &/|second =pairs)))
+                                         (&/$Item =input (&/$Item =else (&/|map &/|second =pairs)))
                                          (&/|map &/|first =pairs)))))))
 
 (defn analyse-proc [analyse exo-type proc ?values]
diff --git a/lux-bootstrapper/src/lux/analyser/proc/jvm.clj b/lux-bootstrapper/src/lux/analyser/proc/jvm.clj
index 78362601d..38310e60c 100644
--- a/lux-bootstrapper/src/lux/analyser/proc/jvm.clj
+++ b/lux-bootstrapper/src/lux/analyser/proc/jvm.clj
@@ -93,8 +93,8 @@
   (|do [[_ clean-types] (&/fold% (fn [idx+types gtype-var]
                                    (|do [:let [[idx types] idx+types]
                                          [idx* real-type] (clean-gtype-var idx gtype-var)]
-                                     (return (&/T [idx* (&/$Cons real-type types)]))))
-                                 (&/T [1 &/$Nil])
+                                     (return (&/T [idx* (&/$Item real-type types)]))))
+                                 (&/T [1 &/$End])
                                  gtype-vars)]
     (return clean-types)))
 
@@ -118,7 +118,7 @@
   (|case obj-type
     (&/$Primitive class targs)
     (if (= (&/|length targs) (&/|length gvars))
-      (|let [gtype-env (&/fold2 (fn [m ^TypeVariable g t] (&/$Cons (&/T [(.getName g) t]) m))
+      (|let [gtype-env (&/fold2 (fn [m ^TypeVariable g t] (&/$Item (&/T [(.getName g) t]) m))
                                 (&/|table)
                                 gvars
                                 targs)]
@@ -191,14 +191,14 @@
     
     (&/$GenericClass name params)
     (case name
-      "boolean" (return (&/$Primitive "java.lang.Boolean" &/$Nil))
-      "byte"    (return (&/$Primitive "java.lang.Byte" &/$Nil))
-      "short"   (return (&/$Primitive "java.lang.Short" &/$Nil))
-      "int"     (return (&/$Primitive "java.lang.Integer" &/$Nil))
-      "long"    (return (&/$Primitive "java.lang.Long" &/$Nil))
-      "float"   (return (&/$Primitive "java.lang.Float" &/$Nil))
-      "double"  (return (&/$Primitive "java.lang.Double" &/$Nil))
-      "char"    (return (&/$Primitive "java.lang.Character" &/$Nil))
+      "boolean" (return (&/$Primitive "java.lang.Boolean" &/$End))
+      "byte"    (return (&/$Primitive "java.lang.Byte" &/$End))
+      "short"   (return (&/$Primitive "java.lang.Short" &/$End))
+      "int"     (return (&/$Primitive "java.lang.Integer" &/$End))
+      "long"    (return (&/$Primitive "java.lang.Long" &/$End))
+      "float"   (return (&/$Primitive "java.lang.Float" &/$End))
+      "double"  (return (&/$Primitive "java.lang.Double" &/$End))
+      "char"    (return (&/$Primitive "java.lang.Character" &/$End))
       "void"    (return &type/Any)
       ;; else
       (|do [=params (&/map% (partial generic-class->type env) params)]
@@ -209,7 +209,7 @@
       (return (&/$Primitive &host-type/array-data-tag (&/|list =param))))
 
     (&/$GenericWildcard _)
-    (return (&/$ExQ &/$Nil (&/$Parameter 1)))
+    (return (&/$ExQ &/$End (&/$Parameter 1)))
     ))
 
 (defn gen-super-env
@@ -393,10 +393,10 @@
     ))
 
 (do-template [<name> <proc> <from-class> <to-class>]
-  (let [output-type (&/$Primitive <to-class> &/$Nil)]
+  (let [output-type (&/$Primitive <to-class> &/$End)]
     (defn- <name> [analyse exo-type _?value]
-      (|do [:let [(&/$Cons ?value (&/$Nil)) _?value]
-            =value (&&/analyse-1 analyse (&/$Primitive <from-class> &/$Nil) ?value)
+      (|do [:let [(&/$Item ?value (&/$End)) _?value]
+            =value (&&/analyse-1 analyse (&/$Primitive <from-class> &/$End) ?value)
             _ (&type/check exo-type output-type)
             _location &/location]
         (return (&/|list (&&/|meta output-type _location (&&/$proc (&/T ["jvm" <proc>]) (&/|list =value) (&/|list))))))))
@@ -433,11 +433,11 @@
   )
 
 (do-template [<name> <proc> <v1-class> <v2-class> <to-class>]
-  (let [output-type (&/$Primitive <to-class> &/$Nil)]
+  (let [output-type (&/$Primitive <to-class> &/$End)]
     (defn- <name> [analyse exo-type ?values]
-      (|do [:let [(&/$Cons ?value1 (&/$Cons ?value2 (&/$Nil))) ?values]
-            =value1 (&&/analyse-1 analyse (&/$Primitive <v1-class> &/$Nil) ?value1)
-            =value2 (&&/analyse-1 analyse (&/$Primitive <v2-class> &/$Nil) ?value2)
+      (|do [:let [(&/$Item ?value1 (&/$Item ?value2 (&/$End))) ?values]
+            =value1 (&&/analyse-1 analyse (&/$Primitive <v1-class> &/$End) ?value1)
+            =value2 (&&/analyse-1 analyse (&/$Primitive <v2-class> &/$End) ?value2)
             _ (&type/check exo-type output-type)
             _location &/location]
         (return (&/|list (&&/|meta output-type _location (&&/$proc (&/T ["jvm" <proc>]) (&/|list =value1 =value2) (&/|list))))))))
@@ -458,10 +458,10 @@
   )
 
 (do-template [<name> <proc> <input-class> <output-class>]
-  (let [input-type (&/$Primitive <input-class> &/$Nil)
-        output-type (&/$Primitive <output-class> &/$Nil)]
+  (let [input-type (&/$Primitive <input-class> &/$End)
+        output-type (&/$Primitive <output-class> &/$End)]
     (defn- <name> [analyse exo-type ?values]
-      (|do [:let [(&/$Cons x (&/$Cons y (&/$Nil))) ?values]
+      (|do [:let [(&/$Item x (&/$Item y (&/$End))) ?values]
             =x (&&/analyse-1 analyse input-type x)
             =y (&&/analyse-1 analyse input-type y)
             _ (&type/check exo-type output-type)
@@ -513,10 +513,10 @@
 (let [length-type &type/Nat
       idx-type &type/Nat]
   (do-template [<elem-class> <array-class> <new-name> <new-tag> <load-name> <load-tag> <store-name> <store-tag>]
-    (let [elem-type (&/$Primitive <elem-class> &/$Nil)
-          array-type (&/$Primitive <array-class> &/$Nil)]
+    (let [elem-type (&/$Primitive <elem-class> &/$End)
+          array-type (&/$Primitive <array-class> &/$End)]
       (defn- <new-name> [analyse exo-type ?values]
-        (|do [:let [(&/$Cons length (&/$Nil)) ?values]
+        (|do [:let [(&/$Item length (&/$End)) ?values]
               =length (&&/analyse-1 analyse length-type length)
               _ (&type/check exo-type array-type)
               _location &/location]
@@ -524,7 +524,7 @@
                                      (&&/$proc (&/T ["jvm" <new-tag>]) (&/|list =length) (&/|list)))))))
 
       (defn- <load-name> [analyse exo-type ?values]
-        (|do [:let [(&/$Cons array (&/$Cons idx (&/$Nil))) ?values]
+        (|do [:let [(&/$Item array (&/$Item idx (&/$End))) ?values]
               =array (&&/analyse-1 analyse array-type array)
               =idx (&&/analyse-1 analyse idx-type idx)
               _ (&type/check exo-type elem-type)
@@ -533,7 +533,7 @@
                                      (&&/$proc (&/T ["jvm" <load-tag>]) (&/|list =array =idx) (&/|list)))))))
 
       (defn- <store-name> [analyse exo-type ?values]
-        (|do [:let [(&/$Cons array (&/$Cons idx (&/$Cons elem (&/$Nil)))) ?values]
+        (|do [:let [(&/$Item array (&/$Item idx (&/$Item elem (&/$End)))) ?values]
               =array (&&/analyse-1 analyse array-type array)
               =idx (&&/analyse-1 analyse idx-type idx)
               =elem (&&/analyse-1 analyse elem-type elem)
@@ -563,7 +563,7 @@
 (let [length-type &type/Nat
       idx-type &type/Nat]
   (defn- analyse-jvm-anewarray [analyse exo-type ?values]
-    (|do [:let [(&/$Cons [_ (&/$Text _gclass)] (&/$Cons length (&/$Nil))) ?values]
+    (|do [:let [(&/$Item [_ (&/$Text _gclass)] (&/$Item length (&/$End))) ?values]
           gclass (&reader/with-source "jvm-anewarray" _gclass
                    &&a-parser/parse-gclass)
           gtype-env &/get-type-env
@@ -576,11 +576,11 @@
                                  (&&/$proc (&/T ["jvm" "anewarray"]) (&/|list =length) (&/|list gclass gtype-env)))))))
 
   (defn- analyse-jvm-aaload [analyse exo-type ?values]
-    (|do [:let [(&/$Cons array (&/$Cons idx (&/$Nil))) ?values]
+    (|do [:let [(&/$Item array (&/$Item idx (&/$End))) ?values]
           =array (&&/analyse-1+ analyse array)
           [arr-class arr-params] (ensure-object (&&/expr-type* =array))
           _ (&/assert! (= &host-type/array-data-tag arr-class) (str "[Analyser Error] Expected array. Instead got: " arr-class))
-          :let [(&/$Cons inner-arr-type (&/$Nil)) arr-params]
+          :let [(&/$Item inner-arr-type (&/$End)) arr-params]
           =idx (&&/analyse-1 analyse idx-type idx)
           _ (&type/check exo-type inner-arr-type)
           _location &/location]
@@ -588,12 +588,12 @@
                                  (&&/$proc (&/T ["jvm" "aaload"]) (&/|list =array =idx) (&/|list)))))))
 
   (defn- analyse-jvm-aastore [analyse exo-type ?values]
-    (|do [:let [(&/$Cons array (&/$Cons idx (&/$Cons elem (&/$Nil)))) ?values]
+    (|do [:let [(&/$Item array (&/$Item idx (&/$Item elem (&/$End)))) ?values]
           =array (&&/analyse-1+ analyse array)
           :let [array-type (&&/expr-type* =array)]
           [arr-class arr-params] (ensure-object array-type)
           _ (&/assert! (= &host-type/array-data-tag arr-class) (str "[Analyser Error] Expected array. Instead got: " arr-class))
-          :let [(&/$Cons inner-arr-type (&/$Nil)) arr-params]
+          :let [(&/$Item inner-arr-type (&/$End)) arr-params]
           =idx (&&/analyse-1 analyse idx-type idx)
           =elem (&&/analyse-1 analyse inner-arr-type elem)
           _ (&type/check exo-type array-type)
@@ -602,7 +602,7 @@
                                  (&&/$proc (&/T ["jvm" "aastore"]) (&/|list =array =idx =elem) (&/|list))))))))
 
 (defn- analyse-jvm-arraylength [analyse exo-type ?values]
-  (|do [:let [(&/$Cons array (&/$Nil)) ?values]
+  (|do [:let [(&/$Item array (&/$End)) ?values]
         =array (&&/analyse-1+ analyse array)
         [arr-class arr-params] (ensure-object (&&/expr-type* =array))
         _ (&/assert! (array-class? arr-class) (str "[Analyser Error] Expected array. Instead got: " arr-class))
@@ -613,7 +613,7 @@
                                )))))
 
 (defn- analyse-jvm-object-null? [analyse exo-type ?values]
-  (|do [:let [(&/$Cons object (&/$Nil)) ?values]
+  (|do [:let [(&/$Item object (&/$End)) ?values]
         =object (&&/analyse-1+ analyse object)
         _ (ensure-object (&&/expr-type* =object))
         :let [output-type &type/Bit]
@@ -623,15 +623,15 @@
                                (&&/$proc (&/T ["jvm" "object null?"]) (&/|list =object) (&/|list)))))))
 
 (defn- analyse-jvm-object-null [analyse exo-type ?values]
-  (|do [:let [(&/$Nil) ?values]
-        :let [output-type (&/$Primitive &host-type/null-data-tag &/$Nil)]
+  (|do [:let [(&/$End) ?values]
+        :let [output-type (&/$Primitive &host-type/null-data-tag &/$End)]
         _ (&type/check exo-type output-type)
         _location &/location]
     (return (&/|list (&&/|meta exo-type _location
                                (&&/$proc (&/T ["jvm" "object null"]) (&/|list) (&/|list)))))))
 
 (defn analyse-jvm-object-synchronized [analyse exo-type ?values]
-  (|do [:let [(&/$Cons ?monitor (&/$Cons ?expr (&/$Nil))) ?values]
+  (|do [:let [(&/$Item ?monitor (&/$Item ?expr (&/$End))) ?values]
         =monitor (&&/analyse-1+ analyse ?monitor)
         _ (ensure-object (&&/expr-type* =monitor))
         =expr (&&/analyse-1 analyse exo-type ?expr)
@@ -640,9 +640,9 @@
                                (&&/$proc (&/T ["jvm" "object synchronized"]) (&/|list =monitor =expr) (&/|list)))))))
 
 (defn- analyse-jvm-throw [analyse exo-type ?values]
-  (|do [:let [(&/$Cons ?ex (&/$Nil)) ?values]
+  (|do [:let [(&/$Item ?ex (&/$End)) ?values]
         =ex (&&/analyse-1+ analyse ?ex)
-        _ (&type/check (&/$Primitive "java.lang.Throwable" &/$Nil) (&&/expr-type* =ex))
+        _ (&type/check (&/$Primitive "java.lang.Throwable" &/$End) (&&/expr-type* =ex))
         [throw-class throw-params] (ensure-object (&&/expr-type* =ex))
         _location &/location
         _ (&type/check exo-type &type/Nothing)]
@@ -651,10 +651,10 @@
 
 (defn- analyse-jvm-getstatic [analyse exo-type class field ?values]
   (|do [!class! (&/de-alias-class class)
-        :let [(&/$Nil) ?values]
+        :let [(&/$End) ?values]
         class-loader &/loader
         [gvars gtype] (&host/lookup-static-field class-loader !class! field)
-        =type (&host-type/instance-param &type/existential &/$Nil gtype)
+        =type (&host-type/instance-param &type/existential &/$End gtype)
         :let [output-type =type]
         _ (&type/check exo-type output-type)
         _location &/location]
@@ -663,7 +663,7 @@
 
 (defn- analyse-jvm-getfield [analyse exo-type class field ?values]
   (|do [!class! (&/de-alias-class class)
-        :let [(&/$Cons object (&/$Nil)) ?values]
+        :let [(&/$Item object (&/$End)) ?values]
         class-loader &/loader
         =object (&&/analyse-1+ analyse object)
         _ (ensure-object (&&/expr-type* =object))
@@ -677,11 +677,11 @@
 
 (defn- analyse-jvm-putstatic [analyse exo-type class field ?values]
   (|do [!class! (&/de-alias-class class)
-        :let [(&/$Cons value (&/$Nil)) ?values]
+        :let [(&/$Item value (&/$End)) ?values]
         class-loader &/loader
         [gvars gtype] (&host/lookup-static-field class-loader !class! field)
         :let [gclass (&host-type/gtype->gclass gtype)]
-        =type (&host-type/instance-param &type/existential &/$Nil gtype)
+        =type (&host-type/instance-param &type/existential &/$End gtype)
         =value (&&/analyse-1 analyse =type value)
         :let [output-type &type/Any]
         _ (&type/check exo-type output-type)
@@ -691,7 +691,7 @@
 
 (defn- analyse-jvm-putfield [analyse exo-type class field ?values]
   (|do [!class! (&/de-alias-class class)
-        :let [(&/$Cons object (&/$Cons value (&/$Nil))) ?values]
+        :let [(&/$Item object (&/$Item value (&/$End))) ?values]
         class-loader &/loader
         =object (&&/analyse-1+ analyse object)
         :let [obj-type (&&/expr-type* =object)]
@@ -708,7 +708,7 @@
 
 (defn- analyse-method-call-helper [analyse exo-type gret gtype-env gtype-vars gtype-args args]
   (|case gtype-vars
-    (&/$Nil)
+    (&/$End)
     (|do [arg-types (&/map% (partial &host-type/instance-param &type/existential gtype-env) gtype-args)
           =arg-types (&/map% &type/show-type+ arg-types)
           =args (&/map2% (partial &&/analyse-1 analyse) arg-types args)
@@ -716,11 +716,11 @@
           _ (&type/check exo-type (as-otype+ =gret))]
       (return (&/T [=gret =args])))
     
-    (&/$Cons ^TypeVariable gtv gtype-vars*)
+    (&/$Item ^TypeVariable gtv gtype-vars*)
     (&type/with-var
       (fn [$var]
         (|do [:let [(&/$Var _id) $var
-                    gtype-env* (&/$Cons (&/T [(.getName gtv) $var]) gtype-env)]
+                    gtype-env* (&/$Item (&/T [(.getName gtv) $var]) gtype-env)]
               [=gret =args] (analyse-method-call-helper analyse exo-type gret gtype-env* gtype-vars* gtype-args args)
               ==gret (&type/clean $var =gret)
               ==args (&/map% (partial &&/clean-analysis $var) =args)]
@@ -733,7 +733,7 @@
                                                                                                                     !class!
                                                                                                                     sub-class)
                                                                            sub-params)]
-    (return (&/fold2 (fn [m ^TypeVariable g t] (&/$Cons (&/T [(.getName g) t]) m))
+    (return (&/fold2 (fn [m ^TypeVariable g t] (&/$Item (&/T [(.getName g) t]) m))
                      (&/|table)
                      parent-gvars
                      super-params*))))
@@ -751,20 +751,20 @@
               (&/fail-with-loc (str "[Analyser Error] Unknown class: " !class!))))]
     (return (&/T [!class! class-loader]))))
 
-(let [dummy-type-param (&/$Primitive "java.lang.Object" &/$Nil)]
+(let [dummy-type-param (&/$Primitive "java.lang.Object" &/$End)]
   (do-template [<name> <tag> <only-interface?>]
     (defn- <name> [analyse exo-type class method classes ?values]
-      (|do [:let [(&/$Cons object args) ?values]
+      (|do [:let [(&/$Item object args) ?values]
             [!class! class-loader] (check-method! <only-interface?> class method)
             [gret exceptions parent-gvars gvars gargs] (if (= "<init>" method)
-                                                         (return (&/T [Void/TYPE &/$Nil &/$Nil &/$Nil &/$Nil]))
+                                                         (return (&/T [Void/TYPE &/$End &/$End &/$End &/$End]))
                                                          (&host/lookup-virtual-method class-loader !class! method classes))
             =object (&&/analyse-1+ analyse object)
             gtype-env (up-cast class parent-gvars class-loader !class! (&&/expr-type* =object))
             [output-type =args] (analyse-method-call-helper analyse exo-type gret gtype-env gvars gargs args)
             _location &/location]
         (return (&/|list (&&/|meta exo-type _location
-                                   (&&/$proc (&/T ["jvm" <tag>]) (&/$Cons =object =args) (&/|list class method classes output-type gret)))))))
+                                   (&&/$proc (&/T ["jvm" <tag>]) (&/$Item =object =args) (&/|list class method classes output-type gret)))))))
 
     analyse-jvm-invokevirtual   "invokevirtual"   false
     analyse-jvm-invokespecial   "invokespecial"   false
@@ -784,17 +784,17 @@
 
 (defn- analyse-jvm-new-helper [analyse gtype gtype-env gtype-vars gtype-args args]
   (|case gtype-vars
-    (&/$Nil)
+    (&/$End)
     (|do [arg-types (&/map% (partial &host-type/instance-param &type/existential gtype-env) gtype-args)
           =args (&/map2% (partial &&/analyse-1 analyse) arg-types args)
           gtype-vars* (->> gtype-env (&/|map &/|second) (clean-gtype-vars))]
       (return (&/T [(make-gtype gtype gtype-vars*)
                     =args])))
     
-    (&/$Cons ^TypeVariable gtv gtype-vars*)
+    (&/$Item ^TypeVariable gtv gtype-vars*)
     (&type/with-var
       (fn [$var]
-        (|do [:let [gtype-env* (&/$Cons (&/T [(.getName gtv) $var]) gtype-env)]
+        (|do [:let [gtype-env* (&/$Item (&/T [(.getName gtv) $var]) gtype-env)]
               [=gret =args] (analyse-jvm-new-helper analyse gtype gtype-env* gtype-vars* gtype-args args)
               ==gret (&type/clean $var =gret)
               ==args (&/map% (partial &&/clean-analysis $var) =args)]
@@ -813,7 +813,7 @@
                                (&&/$proc (&/T ["jvm" "new"]) =args (&/|list class classes)))))))
 
 (defn- analyse-jvm-instanceof [analyse exo-type class ?values]
-  (|do [:let [(&/$Cons object (&/$Nil)) ?values]
+  (|do [:let [(&/$Item object (&/$End)) ?values]
         =object (&&/analyse-1+ analyse object)
         _ (ensure-object (&&/expr-type* =object))
         :let [output-type &type/Bit]
@@ -823,7 +823,7 @@
                                (&&/$proc (&/T ["jvm" "instanceof"]) (&/|list =object) (&/|list class)))))))
 
 (defn- analyse-jvm-object-class [analyse exo-type ?values]
-  (|do [:let [(&/$Cons [_ (&/$Text _class-name)] (&/$Nil)) ?values]
+  (|do [:let [(&/$Item [_ (&/$Text _class-name)] (&/$End)) ?values]
         ^ClassLoader class-loader &/loader
         _ (try (do (.loadClass class-loader _class-name)
                  (return nil))
@@ -849,14 +849,14 @@
           :let [[?name ?params] class-decl
                 full-name (str (string/replace module "/" ".") "." ?name)
                 class-decl* (&/T [full-name ?params])
-                all-supers (&/$Cons super-class interfaces)]
+                all-supers (&/$Item super-class interfaces)]
           class-env (make-type-env ?params)
           =fields (&/map% (partial analyse-field analyse class-env) ?fields)
           _ (&host/use-dummy-class class-decl super-class interfaces &/$None =fields methods)
           =methods (&/map% (partial analyse-method analyse class-decl* class-env all-supers) methods)
           ;; TODO: Uncomment
           ;; _ (check-method-completion all-supers =methods)
-          _ (compile-class class-decl super-class interfaces =inheritance-modifier =anns =fields =methods &/$Nil &/$None)
+          _ (compile-class class-decl super-class interfaces =inheritance-modifier =anns =fields =methods &/$End &/$None)
           _ &/pop-dummy-name
           :let [_ (println 'CLASS full-name)]
           _location &/location]
@@ -869,7 +869,7 @@
     source))
 
 (defn- analyse-methods [analyse class-decl all-supers methods]
-  (|do [=methods (&/map% (partial analyse-method analyse class-decl &/$Nil all-supers) methods)
+  (|do [=methods (&/map% (partial analyse-method analyse class-decl &/$End all-supers) methods)
         ;; TODO: Uncomment
         ;; _ (check-method-completion all-supers =methods)
         =captured &&env/captured-vars]
@@ -883,42 +883,42 @@
 (let [default-<init> (fn [ctor-args]
                        (&/$ConstructorMethodSyntax (&/T [&/$PublicPM ;; privacy-modifier
                                                          false ;; strict
-                                                         &/$Nil ;; anns
-                                                         &/$Nil ;; gvars
-                                                         &/$Nil ;; exceptions
-                                                         &/$Nil ;; inputs
+                                                         &/$End ;; anns
+                                                         &/$End ;; gvars
+                                                         &/$End ;; exceptions
+                                                         &/$End ;; inputs
                                                          ctor-args ;; ctor-args
-                                                         (&/$Tuple &/$Nil) ;; body
+                                                         (&/$Tuple &/$End) ;; body
                                                          ])))
       captured-slot-class "java.lang.Object"
-      captured-slot-type (&/$GenericClass captured-slot-class &/$Nil)]
+      captured-slot-type (&/$GenericClass captured-slot-class &/$End)]
   (defn- analyse-jvm-anon-class [analyse compile-class exo-type super-class interfaces ctor-args methods]
     (&/with-closure
       (|do [[module scope] (get-names)
             :let [name (->> scope &/|reverse &/|tail &host/location)
-                  class-decl (&/T [name &/$Nil])
+                  class-decl (&/T [name &/$End])
                   anon-class (str (string/replace module "/" ".") "." name)
-                  class-type-decl (&/T [anon-class &/$Nil])
-                  anon-class-type (&/$Primitive anon-class &/$Nil)]
+                  class-type-decl (&/T [anon-class &/$End])
+                  anon-class-type (&/$Primitive anon-class &/$End)]
             =ctor-args (&/map% (fn [ctor-arg]
                                  (|let [[arg-type arg-term] ctor-arg]
                                    (|do [=arg-term (&&/analyse-1+ analyse arg-term)]
                                      (return (&/T [arg-type =arg-term])))))
                                ctor-args)
             _ (->> methods
-                   (&/$Cons (default-<init> =ctor-args))
-                   (&host/use-dummy-class class-decl super-class interfaces (&/$Some =ctor-args) &/$Nil))
-            [=methods =captured] (let [all-supers (&/$Cons super-class interfaces)]
+                   (&/$Item (default-<init> =ctor-args))
+                   (&host/use-dummy-class class-decl super-class interfaces (&/$Some =ctor-args) &/$End))
+            [=methods =captured] (let [all-supers (&/$Item super-class interfaces)]
                                    (analyse-methods analyse class-type-decl all-supers methods))
             _ (let [=fields (&/|map (fn [^objects idx+capt]
                                       (|let [[idx _] idx+capt]
                                         (&/$VariableFieldAnalysis (str &c!base/closure-prefix idx)
                                                                   &/$PublicPM
                                                                   &/$FinalSM
-                                                                  &/$Nil
+                                                                  &/$End
                                                                   captured-slot-type)))
                                     (&/enumerate =captured))]
-                (compile-class class-decl super-class interfaces &/$DefaultIM &/$Nil =fields =methods =captured (&/$Some =ctor-args)))
+                (compile-class class-decl super-class interfaces &/$DefaultIM &/$End =fields =methods =captured (&/$Some =ctor-args)))
             _ &/pop-dummy-name
             _location &/location]
         (let [sources (&/|map captured-source =captured)]
diff --git a/lux-bootstrapper/src/lux/analyser/record.clj b/lux-bootstrapper/src/lux/analyser/record.clj
index 3d3d8169f..53f6c4d5c 100644
--- a/lux-bootstrapper/src/lux/analyser/record.clj
+++ b/lux-bootstrapper/src/lux/analyser/record.clj
@@ -7,13 +7,14 @@
                           [module :as &&module])))
 
 ;; [Exports]
-(defn order-record [pairs]
+(defn order-record
   "(-> (List (, Syntax Syntax)) (Lux (List Syntax)))"
+  [pairs]
   (|do [[tag-group tag-type] (|case pairs
-                               (&/$Nil)
-                               (return (&/T [&/$Nil &type/Any]))
+                               (&/$End)
+                               (return (&/T [&/$End &type/Any]))
                                
-                               (&/$Cons [[_ (&/$Tag tag1)] _] _)
+                               (&/$Item [[_ (&/$Tag tag1)] _] _)
                                (|do [[module name] (&&/resolved-ident tag1)
                                      tags (&&module/tag-group module name)
                                      type (&&module/tag-type module name)]
diff --git a/lux-bootstrapper/src/lux/base.clj b/lux-bootstrapper/src/lux/base.clj
index 648b3341c..1367bdc1c 100644
--- a/lux-bootstrapper/src/lux/base.clj
+++ b/lux-bootstrapper/src/lux/base.clj
@@ -60,8 +60,8 @@
 
 ;; List
 (defvariant
-  ("Nil" 0)
-  ("Cons" 2))
+  ("End" 0)
+  ("Item" 2))
 
 ;; Maybe
 (defvariant
@@ -160,6 +160,7 @@
    "seed"
    "scope-type-vars"
    "extensions"
+   "eval"
    "host"])
 
 (defvariant
@@ -285,71 +286,71 @@
 
 (defmacro |list [& elems]
   (reduce (fn [tail head]
-            `($Cons ~head ~tail))
-          `$Nil
+            `($Item ~head ~tail))
+          `$End
           (reverse elems)))
 
 (defmacro |table [& elems]
   (reduce (fn [table [k v]]
             `(|put ~k ~v ~table))
-          `$Nil
+          `$End
           (reverse (partition 2 elems))))
 
 (defn |get [slot table]
   (|case table
-    ($Nil)
+    ($End)
     nil
     
-    ($Cons [k v] table*)
+    ($Item [k v] table*)
     (if (= k slot)
       v
       (recur slot table*))))
 
 (defn |put [slot value table]
   (|case table
-    ($Nil)
-    ($Cons (T [slot value]) $Nil)
+    ($End)
+    ($Item (T [slot value]) $End)
     
-    ($Cons [k v] table*)
+    ($Item [k v] table*)
     (if (= k slot)
-      ($Cons (T [slot value]) table*)
-      ($Cons (T [k v]) (|put slot value table*)))
+      ($Item (T [slot value]) table*)
+      ($Item (T [k v]) (|put slot value table*)))
     ))
 
 (defn |remove [slot table]
   (|case table
-    ($Nil)
+    ($End)
     table
     
-    ($Cons [k v] table*)
+    ($Item [k v] table*)
     (if (= k slot)
       table*
-      ($Cons (T [k v]) (|remove slot table*)))))
+      ($Item (T [k v]) (|remove slot table*)))))
 
 (defn |update [k f table]
   (|case table
-    ($Nil)
+    ($End)
     table
 
-    ($Cons [k* v] table*)
+    ($Item [k* v] table*)
     (if (= k k*)
-      ($Cons (T [k* (f v)]) table*)
-      ($Cons (T [k* v]) (|update k f table*)))))
+      ($Item (T [k* (f v)]) table*)
+      ($Item (T [k* v]) (|update k f table*)))))
 
 (defn |head [xs]
   (|case xs
-    ($Nil)
+    ($End)
     (assert false (prn-str '|head))
 
-    ($Cons x _)
+    ($Item x _)
     x))
 
 (defn |tail [xs]
   (|case xs
-    ($Nil)
+    ($End)
     (assert false (prn-str '|tail))
 
-    ($Cons _ xs*)
+    ($Item _ xs*)
     xs*))
 
 ;; [Resources/Monads]
@@ -395,19 +396,19 @@
 
 (defn |++ [xs ys]
   (|case xs
-    ($Nil)
+    ($End)
     ys
 
-    ($Cons x xs*)
-    ($Cons x (|++ xs* ys))))
+    ($Item x xs*)
+    ($Item x (|++ xs* ys))))
 
 (defn |map [f xs]
   (|case xs
-    ($Nil)
+    ($End)
     xs
 
-    ($Cons x xs*)
-    ($Cons (f x) (|map f xs*))
+    ($Item x xs*)
+    ($Item (f x) (|map f xs*))
 
     _
     (assert false (prn-str '|map f (adt->text xs)))))
@@ -416,99 +417,99 @@
   "(All [a] (-> (List a) Bit))"
   [xs]
   (|case xs
-    ($Nil)
+    ($End)
     true
 
-    ($Cons _ _)
+    ($Item _ _)
     false))
 
 (defn |filter
   "(All [a] (-> (-> a Bit) (List a) (List a)))"
   [p xs]
   (|case xs
-    ($Nil)
+    ($End)
     xs
 
-    ($Cons x xs*)
+    ($Item x xs*)
     (if (p x)
-      ($Cons x (|filter p xs*))
+      ($Item x (|filter p xs*))
       (|filter p xs*))))
 
 (defn flat-map
   "(All [a b] (-> (-> a (List b)) (List a) (List b)))"
   [f xs]
   (|case xs
-    ($Nil)
+    ($End)
     xs
 
-    ($Cons x xs*)
+    ($Item x xs*)
     (|++ (f x) (flat-map f xs*))))
 
 (defn |split-with [p xs]
   (|case xs
-    ($Nil)
+    ($End)
     (T [xs xs])
 
-    ($Cons x xs*)
+    ($Item x xs*)
     (if (p x)
       (|let [[pre post] (|split-with p xs*)]
-        (T [($Cons x pre) post]))
-      (T [$Nil xs]))))
+        (T [($Item x pre) post]))
+      (T [$End xs]))))
 
 (defn |contains? [k table]
   (|case table
-    ($Nil)
+    ($End)
     false
 
-    ($Cons [k* _] table*)
+    ($Item [k* _] table*)
     (or (= k k*)
         (|contains? k table*))))
 
 (defn |member? [x xs]
   (|case xs
-    ($Nil)
+    ($End)
     false
 
-    ($Cons x* xs*)
+    ($Item x* xs*)
     (or (= x x*) (|member? x xs*))))
 
 (defn fold [f init xs]
   (|case xs
-    ($Nil)
+    ($End)
     init
 
-    ($Cons x xs*)
+    ($Item x xs*)
     (recur f (f init x) xs*)))
 
 (defn fold% [f init xs]
   (|case xs
-    ($Nil)
+    ($End)
     (return init)
 
-    ($Cons x xs*)
+    ($Item x xs*)
     (|do [init* (f init x)]
       (fold% f init* xs*))))
 
 (defn folds [f init xs]
   (|case xs
-    ($Nil)
+    ($End)
     (|list init)
 
-    ($Cons x xs*)
-    ($Cons init (folds f (f init x) xs*))))
+    ($Item x xs*)
+    ($Item init (folds f (f init x) xs*))))
 
 (defn |length [xs]
   (fold (fn [acc _] (inc acc)) 0 xs))
 
 (defn |range* [from to]
   (if (<= from to)
-    ($Cons from (|range* (inc from) to))
-    $Nil))
+    ($Item from (|range* (inc from) to))
+    $End))
 
 (let [|range* (fn |range* [from to]
                 (if (< from to)
-                  ($Cons from (|range* (inc from) to))
-                  $Nil))]
+                  ($Item from (|range* (inc from) to))
+                  $End))]
   (defn |range [n]
     (|range* 0 n)))
 
@@ -522,68 +523,68 @@
 
 (defn zip2 [xs ys]
   (|case [xs ys]
-    [($Cons x xs*) ($Cons y ys*)]
-    ($Cons (T [x y]) (zip2 xs* ys*))
+    [($Item x xs*) ($Item y ys*)]
+    ($Item (T [x y]) (zip2 xs* ys*))
 
     [_ _]
-    $Nil))
+    $End))
 
 (defn |keys [plist]
   (|case plist
-    ($Nil)
-    $Nil
+    ($End)
+    $End
     
-    ($Cons [k v] plist*)
-    ($Cons k (|keys plist*))))
+    ($Item [k v] plist*)
+    ($Item k (|keys plist*))))
 
 (defn |vals [plist]
   (|case plist
-    ($Nil)
-    $Nil
+    ($End)
+    $End
     
-    ($Cons [k v] plist*)
-    ($Cons v (|vals plist*))))
+    ($Item [k v] plist*)
+    ($Item v (|vals plist*))))
 
 (defn |interpose [sep xs]
   (|case xs
-    ($Nil)
+    ($End)
     xs
 
-    ($Cons _ ($Nil))
+    ($Item _ ($End))
     xs
     
-    ($Cons x xs*)
-    ($Cons x ($Cons sep (|interpose sep xs*)))))
+    ($Item x xs*)
+    ($Item x ($Item sep (|interpose sep xs*)))))
 
 (do-template [<name> <joiner>]
   (defn <name> [f xs]
     (|case xs
-      ($Nil)
+      ($End)
       (return xs)
 
-      ($Cons x xs*)
+      ($Item x xs*)
       (|do [y (f x)
             ys (<name> f xs*)]
         (return (<joiner> y ys)))))
 
-  map%      $Cons
+  map%      $Item
   flat-map% |++)
 
 (defn list-join [xss]
-  (fold |++ $Nil xss))
+  (fold |++ $End xss))
 
 (defn |as-pairs [xs]
   (|case xs
-    ($Cons x ($Cons y xs*))
-    ($Cons (T [x y]) (|as-pairs xs*))
+    ($Item x ($Item y xs*))
+    ($Item (T [x y]) (|as-pairs xs*))
 
     _
-    $Nil))
+    $End))
 
 (defn |reverse [xs]
   (fold (fn [tail head]
-          ($Cons head tail))
-        $Nil
+          ($Item head tail))
+        $End
         xs))
 
 (defn add-loc [meta ^String msg]
@@ -607,17 +608,17 @@
 
 (defn try-all% [monads]
   (|case monads
-    ($Nil)
+    ($End)
     (fail "[Error] There are no alternatives to try!")
 
-    ($Cons m monads*)
+    ($Item m monads*)
     (fn [state]
       (let [output (m state)]
         (|case [output monads*]
           [($Right _) _]
           output
 
-          [_ ($Nil)]
+          [_ ($End)]
           output
           
           [_ _]
@@ -627,17 +628,17 @@
 
 (defn try-all-% [prefix monads]
   (|case monads
-    ($Nil)
+    ($End)
     (fail "[Error] There are no alternatives to try!")
 
-    ($Cons m monads*)
+    ($Item m monads*)
     (fn [state]
       (let [output (m state)]
         (|case [output monads*]
           [($Right _) _]
           output
 
-          [_ ($Nil)]
+          [_ ($End)]
           output
 
           [($Left ^String error) _]
@@ -662,10 +663,10 @@
   "(All [a b] (-> (-> a (Maybe b)) (List a) (Maybe b)))"
   [f xs]
   (|case xs
-    ($Nil)
+    ($End)
     $None
 
-    ($Cons x xs*)
+    ($Item x xs*)
     (|case (f x)
       ($None) (|some f xs*)
       output  output)
@@ -719,7 +720,7 @@
 
 (defn env [name old-name]
   (T [;; name
-      ($Cons name old-name)
+      ($Item name old-name)
       ;; inner
       0
       ;; locals
@@ -792,7 +793,7 @@
   (with-jvm-host-slot $type-env (partial |++ type-env) body))
 
 (defn push-dummy-name [real-name store-name]
-  (change-jvm-host-slot $dummy-mappings (partial $Cons (T [real-name store-name]))))
+  (change-jvm-host-slot $dummy-mappings (partial $Item (T [real-name store-name]))))
 
 (def pop-dummy-name
   (change-jvm-host-slot $dummy-mappings |tail))
@@ -823,7 +824,7 @@
   (T [;; "lux;info"
       (default-info name mode)
       ;; "lux;source"
-      $Nil
+      $End
       ;; "lux;location"
       (T ["" -1 -1])
       ;; "current-module"
@@ -831,7 +832,7 @@
       ;; "lux;modules"
       (|table)
       ;; "lux;scopes"
-      $Nil
+      $End
       ;; "lux;type-context"
       +init-type-context+
       ;; "lux;expected"
@@ -839,9 +840,11 @@
       ;; "lux;seed"
       0
       ;; scope-type-vars
-      $Nil
+      $End
       ;; extensions
-      nil
+      "" ;; This is an invalid value. But I don't expect extensions to be used with the bootstrapping compiler.
+      ;; eval
+      "" ;; This is an invalid value. But I don't expect eval to be used with the bootstrapping compiler.
       ;; "lux;host"
       host-data]
      ))
@@ -903,21 +906,21 @@
 
 (defn ->seq [xs]
   (|case xs
-    ($Nil)
+    ($End)
     (list)
 
-    ($Cons x xs*)
+    ($Item x xs*)
     (cons x (->seq xs*))))
 
 (defn ->list [seq]
   (if (empty? seq)
-    $Nil
-    ($Cons (first seq) (->list (rest seq)))))
+    $End
+    ($Item (first seq) (->list (rest seq)))))
 
 (defn |repeat [n x]
   (if (> n 0)
-    ($Cons x (|repeat (dec n) x))
-    $Nil))
+    ($Item x (|repeat (dec n) x))
+    $End))
 
 (def get-module-name
   (fn [state]
@@ -946,7 +949,7 @@
 (defn with-scope [name body]
   (fn [state]
     (let [old-name (->> state (get$ $scopes) |head (get$ $name))
-          output (body (update$ $scopes #($Cons (env name old-name) %) state))]
+          output (body (update$ $scopes #($Item (env name old-name) %) state))]
       (|case output
         ($Right state* datum)
         (return* (update$ $scopes |tail state*) datum)
@@ -962,7 +965,7 @@
                        (return (->> top (get$ $inner) str)))]
     (fn [state]
       (let [body* (with-scope closure-name body)]
-        (run-state body* (update$ $scopes #($Cons (update$ $inner inc (|head %))
+        (run-state body* (update$ $scopes #($Item (update$ $inner inc (|head %))
                                                   (|tail %))
                                   state))))))
 
@@ -974,10 +977,10 @@
 
 (defn |last [xs]
   (|case xs
-    ($Cons x ($Nil))
+    ($Item x ($End))
     x
 
-    ($Cons x xs*)
+    ($Item x xs*)
     (|last xs*)
 
     _
@@ -1263,11 +1266,11 @@
 
 (defn fold2% [f init xs ys]
   (|case [xs ys]
-    [($Cons x xs*) ($Cons y ys*)]
+    [($Item x xs*) ($Item y ys*)]
     (|do [init* (f init x y)]
       (fold2% f init* xs* ys*))
 
-    [($Nil) ($Nil)]
+    [($End) ($End)]
     (return init)
 
     [_ _]
@@ -1275,32 +1278,32 @@
 
 (defn map2% [f xs ys]
   (|case [xs ys]
-    [($Cons x xs*) ($Cons y ys*)]
+    [($Item x xs*) ($Item y ys*)]
     (|do [z (f x y)
           zs (map2% f xs* ys*)]
-      (return ($Cons z zs)))
+      (return ($Item z zs)))
 
-    [($Nil) ($Nil)]
-    (return $Nil)
+    [($End) ($End)]
+    (return $End)
 
     [_ _]
     (assert false "Lists do not match in size.")))
 
 (defn map2 [f xs ys]
   (|case [xs ys]
-    [($Cons x xs*) ($Cons y ys*)]
-    ($Cons (f x y) (map2 f xs* ys*))
+    [($Item x xs*) ($Item y ys*)]
+    ($Item (f x y) (map2 f xs* ys*))
 
     [_ _]
-    $Nil))
+    $End))
 
 (defn fold2 [f init xs ys]
   (|case [xs ys]
-    [($Cons x xs*) ($Cons y ys*)]
+    [($Item x xs*) ($Item y ys*)]
     (and init
          (fold2 f (f init x y) xs* ys*))
 
-    [($Nil) ($Nil)]
+    [($End) ($End)]
     init
 
     [_ _]
@@ -1312,11 +1315,11 @@
   "(All [a] (-> Int (List a) (List (, Int a))))"
   [idx xs]
   (|case xs
-    ($Cons x xs*)
-    ($Cons (T [idx x])
+    ($Item x xs*)
+    ($Item (T [idx x])
            (enumerate* (inc idx) xs*))
 
-    ($Nil)
+    ($End)
     xs
     ))
 
@@ -1341,7 +1344,7 @@
   "(All [a] (-> Int (List a) (Maybe a)))"
   [idx xs]
   (|case xs
-    ($Cons x xs*)
+    ($Item x xs*)
     (cond (< idx 0)
           $None
 
@@ -1351,7 +1354,7 @@
           :else ;; > 1
           (|at (dec idx) xs*))
 
-    ($Nil)
+    ($End)
     $None))
 
 (defn normalize
@@ -1370,15 +1373,15 @@
 
 (defn |list-put [idx val xs]
   (|case xs
-    ($Nil)
+    ($End)
     $None
     
-    ($Cons x xs*)
+    ($Item x xs*)
     (if (= idx 0)
-      ($Some ($Cons val xs*))
+      ($Some ($Item val xs*))
       (|case (|list-put (dec idx) val xs*)
         ($None)      $None
-        ($Some xs**) ($Some ($Cons x xs**)))
+        ($Some xs**) ($Some ($Item x xs**)))
       )))
 
 (do-template [<name> <default> <op>]
@@ -1386,10 +1389,10 @@
     "(All [a] (-> (-> a Bit) (List a) Bit))"
     [p xs]
     (|case xs
-      ($Nil)
+      ($End)
       <default>
 
-      ($Cons x xs*)
+      ($Item x xs*)
       (<op> (p x) (<name> p xs*))))
 
   |every? true  and
@@ -1415,28 +1418,28 @@
 
 (defn |take [n xs]
   (|case (T [n xs])
-    [0 _]             $Nil
-    [_ ($Nil)]        $Nil
-    [_ ($Cons x xs*)] ($Cons x (|take (dec n) xs*))
+    [0 _]             $End
+    [_ ($End)]        $End
+    [_ ($Item x xs*)] ($Item x (|take (dec n) xs*))
     ))
 
 (defn |drop [n xs]
   (|case (T [n xs])
     [0 _]             xs
-    [_ ($Nil)]        $Nil
-    [_ ($Cons x xs*)] (|drop (dec n) xs*)
+    [_ ($End)]        $End
+    [_ ($Item x xs*)] (|drop (dec n) xs*)
     ))
 
 (defn |but-last [xs]
   (|case xs
-    ($Nil)
-    $Nil
+    ($End)
+    $End
     
-    ($Cons x ($Nil))
-    $Nil
+    ($Item x ($End))
+    $End
 
-    ($Cons x xs*)
-    ($Cons x (|but-last xs*))
+    ($Item x xs*)
+    ($Item x (|but-last xs*))
 
     _
     (assert false (adt->text xs))))
@@ -1447,7 +1450,7 @@
 (defn with-scope-type-var [id body]
   (fn [state]
     (|case (body (set$ $scope-type-vars
-                       ($Cons id (get$ $scope-type-vars state))
+                       ($Item id (get$ $scope-type-vars state))
                        state))
       ($Right [state* output])
       ($Right (T [(set$ $scope-type-vars
diff --git a/lux-bootstrapper/src/lux/compiler/cache.clj b/lux-bootstrapper/src/lux/compiler/cache.clj
index 01e05c8de..bbe9e7882 100644
--- a/lux-bootstrapper/src/lux/compiler/cache.clj
+++ b/lux-bootstrapper/src/lux/compiler/cache.clj
@@ -71,7 +71,7 @@
 
 (defn ^:private parse-tag-groups [^String tags-section]
   (if (= "" tags-section)
-    &/$Nil
+    &/$End
     (-> tags-section
         (.split &&core/entry-separator)
         seq
@@ -131,7 +131,7 @@
   (|do [^String descriptor (&&core/read-module-descriptor! module-name)
         :let [imports (let [imports (vec (.split ^String _imports-section &&core/entry-separator))
                             imports (if (= [""] imports)
-                                      &/$Nil
+                                      &/$End
                                       (&/->list imports))]
                         (&/|map #(first (vec (.split ^String % &&core/datum-separator 2))) imports))]
         cache-table* (&/fold% (fn [cache-table* _module]
@@ -150,7 +150,7 @@
                                  [(&/$Some module-anns) _]))
             def-entries (let [def-entries (vec (.split ^String _defs-section &&core/entry-separator))]
                           (if (= [""] def-entries)
-                            &/$Nil
+                            &/$End
                             (&/->list def-entries)))]
         (|do [_ (install-all-defs-in-module module-name)
               _ (install-module load-def-value module-name module-hash
diff --git a/lux-bootstrapper/src/lux/compiler/cache/ann.clj b/lux-bootstrapper/src/lux/compiler/cache/ann.clj
index 4c08af276..9d5a8e97f 100644
--- a/lux-bootstrapper/src/lux/compiler/cache/ann.clj
+++ b/lux-bootstrapper/src/lux/compiler/cache/ann.clj
@@ -96,12 +96,12 @@
 
 (defn ^:private deserialize-seq [deserializer ^String input]
   (cond (.startsWith input nil-signal)
-        [&/$Nil (.substring input 1)]
+        [&/$End (.substring input 1)]
 
         (.startsWith input cons-signal)
         (when-let [[head ^String input*] (deserializer (.substring input 1))]
           (when-let [[tail ^String input*] (deserialize-seq deserializer input*)]
-            [(&/$Cons head tail) input*]))
+            [(&/$Item head tail) input*]))
         ))
 
 (defn ^:private deserialize-kv [input]
diff --git a/lux-bootstrapper/src/lux/compiler/cache/type.clj b/lux-bootstrapper/src/lux/compiler/cache/type.clj
index 7c622d2c4..f4d33edc1 100644
--- a/lux-bootstrapper/src/lux/compiler/cache/type.clj
+++ b/lux-bootstrapper/src/lux/compiler/cache/type.clj
@@ -64,12 +64,12 @@
 
 (defn ^:private deserialize-list [^String input]
   (cond (.startsWith input nil-signal)
-        [&/$Nil (.substring input 1)]
+        [&/$End (.substring input 1)]
 
         (.startsWith input cons-signal)
         (when-let [[head ^String input*] (deserialize-type (.substring input 1))]
           (when-let [[tail ^String input*] (deserialize-list input*)]
-            [(&/$Cons head tail) input*]))
+            [(&/$Item head tail) input*]))
         ))
 
 (defn ^:private deserialize-type* [^String input]
diff --git a/lux-bootstrapper/src/lux/compiler/jvm.clj b/lux-bootstrapper/src/lux/compiler/jvm.clj
index e2521fec7..d5c490a97 100644
--- a/lux-bootstrapper/src/lux/compiler/jvm.clj
+++ b/lux-bootstrapper/src/lux/compiler/jvm.clj
@@ -200,7 +200,8 @@
                                   (&/set$ &/$source (&reader/from name file-content) state))
                             (&/$Right ?state _)
                             (&/run-state (|do [:let [_ (.visitEnd =class)]
-                                               _ (save-module! name file-hash (.toByteArray =class))]
+                                               _ (save-module! name file-hash (.toByteArray =class))
+                                               :let [_ (println 'MODULE name)]]
                                            (return file-hash))
                                          ?state)
                             
diff --git a/lux-bootstrapper/src/lux/compiler/jvm/lux.clj b/lux-bootstrapper/src/lux/compiler/jvm/lux.clj
index f5fa88e02..973d0e8c6 100644
--- a/lux-bootstrapper/src/lux/compiler/jvm/lux.clj
+++ b/lux-bootstrapper/src/lux/compiler/jvm/lux.clj
@@ -337,7 +337,7 @@
                   $end (new Label)
                   _ (doto main-writer
                       ;; Tail: Begin
-                      (.visitLdcInsn (->> #'&/$Nil meta ::&/idx int)) ;; I
+                      (.visitLdcInsn (->> #'&/$End meta ::&/idx int)) ;; I
                       (.visitInsn Opcodes/ACONST_NULL) ;; I?
                       (.visitLdcInsn &/unit-tag) ;; I?U
                       (.visitMethodInsn Opcodes/INVOKESTATIC &rt/rt-class "sum_make" "(ILjava/lang/Object;Ljava/lang/Object;)[Ljava/lang/Object;") ;; V
@@ -375,13 +375,13 @@
                       (.visitInsn Opcodes/SWAP) ;; I22IV
                       (.visitInsn Opcodes/AASTORE) ;; I2
                       ;; Tuple: End
-                      ;; Cons: Begin
-                      (.visitLdcInsn (->> #'&/$Cons meta ::&/idx int)) ;; I2I
+                      ;; Item: Begin
+                      (.visitLdcInsn (->> #'&/$Item meta ::&/idx int)) ;; I2I
                       (.visitLdcInsn "") ;; I2I?
                       (.visitInsn Opcodes/DUP2_X1) ;; II?2I?
                       (.visitInsn Opcodes/POP2) ;; II?2
                       (.visitMethodInsn Opcodes/INVOKESTATIC &rt/rt-class "sum_make" "(ILjava/lang/Object;Ljava/lang/Object;)[Ljava/lang/Object;") ;; IV
-                      ;; Cons: End
+                      ;; Item: End
                       (.visitInsn Opcodes/SWAP) ;; VI
                       (.visitJumpInsn Opcodes/GOTO $loop)
                       ;; Loop: End
diff --git a/lux-bootstrapper/src/lux/compiler/jvm/proc/common.clj b/lux-bootstrapper/src/lux/compiler/jvm/proc/common.clj
index cd1b77dee..642bd3427 100644
--- a/lux-bootstrapper/src/lux/compiler/jvm/proc/common.clj
+++ b/lux-bootstrapper/src/lux/compiler/jvm/proc/common.clj
@@ -25,7 +25,7 @@
 ;; [Resources]
 (do-template [<name> <op>]
   (defn <name> [compile ?values special-args]
-    (|do [:let [(&/$Cons ?input (&/$Cons ?mask (&/$Nil))) ?values]
+    (|do [:let [(&/$Item ?input (&/$Item ?mask (&/$End))) ?values]
           ^MethodVisitor *writer* &/get-writer
           _ (compile ?input)
           :let [_ (&&/unwrap-long *writer*)]
@@ -43,7 +43,7 @@
 
 (do-template [<op> <name>]
   (defn <name> [compile ?values special-args]
-    (|do [:let [(&/$Cons ?input (&/$Cons ?shift (&/$Nil))) ?values]
+    (|do [:let [(&/$Item ?input (&/$Item ?shift (&/$End))) ?values]
           ^MethodVisitor *writer* &/get-writer
           _ (compile ?input)
           :let [_ (&&/unwrap-long *writer*)]
@@ -61,7 +61,7 @@
   )
 
 (defn ^:private compile-lux-is [compile ?values special-args]
-  (|do [:let [(&/$Cons ?left (&/$Cons ?right (&/$Nil))) ?values]
+  (|do [:let [(&/$Item ?left (&/$Item ?right (&/$End))) ?values]
         ^MethodVisitor *writer* &/get-writer
         _ (compile ?left)
         _ (compile ?right)
@@ -78,7 +78,7 @@
     (return nil)))
 
 (defn ^:private compile-lux-try [compile ?values special-args]
-  (|do [:let [(&/$Cons ?op (&/$Nil)) ?values]
+  (|do [:let [(&/$Item ?op (&/$End)) ?values]
         ^MethodVisitor *writer* &/get-writer
         _ (compile ?op)
         :let [_ (doto *writer*
@@ -88,7 +88,7 @@
 
 (do-template [<name> <opcode> <unwrap> <wrap>]
   (defn <name> [compile ?values special-args]
-    (|do [:let [(&/$Cons ?x (&/$Cons ?y (&/$Nil))) ?values]
+    (|do [:let [(&/$Item ?x (&/$Item ?y (&/$End))) ?values]
           ^MethodVisitor *writer* &/get-writer
           _ (compile ?x)
           :let [_ (doto *writer*
@@ -117,7 +117,7 @@
 
 (do-template [<name> <cmpcode> <cmp-output> <unwrap>]
   (defn <name> [compile ?values special-args]
-    (|do [:let [(&/$Cons ?x (&/$Cons ?y (&/$Nil))) ?values]
+    (|do [:let [(&/$Item ?x (&/$Item ?y (&/$End))) ?values]
           ^MethodVisitor *writer* &/get-writer
           _ (compile ?x)
           :let [_ (doto *writer*
@@ -147,7 +147,7 @@
   )
 
 (defn ^:private compile-frac-encode [compile ?values special-args]
-  (|do [:let [(&/$Cons ?input (&/$Nil)) ?values]
+  (|do [:let [(&/$Item ?input (&/$End)) ?values]
         ^MethodVisitor *writer* &/get-writer
         _ (compile ?input)
         :let [_ (doto *writer*
@@ -156,7 +156,7 @@
     (return nil)))
 
 (defn ^:private compile-frac-decode [compile ?values special-args]
-  (|do [:let [(&/$Cons ?input (&/$Nil)) ?values]
+  (|do [:let [(&/$Item ?input (&/$End)) ?values]
         ^MethodVisitor *writer* &/get-writer
         _ (compile ?input)
         :let [_ (doto *writer*
@@ -165,7 +165,7 @@
     (return nil)))
 
 (defn ^:private compile-int-char [compile ?values special-args]
-  (|do [:let [(&/$Cons ?x (&/$Nil)) ?values]
+  (|do [:let [(&/$Item ?x (&/$End)) ?values]
         ^MethodVisitor *writer* &/get-writer
         _ (compile ?x)
         :let [_ (doto *writer*
@@ -177,7 +177,7 @@
 
 (do-template [<name> <unwrap> <op> <wrap>]
   (defn <name> [compile ?values special-args]
-    (|do [:let [(&/$Cons ?input (&/$Nil)) ?values]
+    (|do [:let [(&/$Item ?input (&/$End)) ?values]
           ^MethodVisitor *writer* &/get-writer
           _ (compile ?input)
           :let [_ (doto *writer*
@@ -191,7 +191,7 @@
   )
 
 (defn ^:private compile-text-eq [compile ?values special-args]
-  (|do [:let [(&/$Cons ?x (&/$Cons ?y (&/$Nil))) ?values]
+  (|do [:let [(&/$Item ?x (&/$Item ?y (&/$End))) ?values]
         ^MethodVisitor *writer* &/get-writer
         _ (compile ?x)
         _ (compile ?y)
@@ -201,7 +201,7 @@
     (return nil)))
 
 (defn ^:private compile-text-lt [compile ?values special-args]
-  (|do [:let [(&/$Cons ?x (&/$Cons ?y (&/$Nil))) ?values]
+  (|do [:let [(&/$Item ?x (&/$Item ?y (&/$End))) ?values]
         ^MethodVisitor *writer* &/get-writer
         _ (compile ?x)
         :let [_ (doto *writer*
@@ -222,7 +222,7 @@
     (return nil)))
 
 (defn compile-text-concat [compile ?values special-args]
-  (|do [:let [(&/$Cons ?x (&/$Cons ?y (&/$Nil))) ?values]
+  (|do [:let [(&/$Item ?x (&/$Item ?y (&/$End))) ?values]
         ^MethodVisitor *writer* &/get-writer
         _ (compile ?x)
         :let [_ (doto *writer*
@@ -235,7 +235,7 @@
     (return nil)))
 
 (defn compile-text-clip [compile ?values special-args]
-  (|do [:let [(&/$Cons ?text (&/$Cons ?offset (&/$Cons ?length (&/$Nil)))) ?values]
+  (|do [:let [(&/$Item ?text (&/$Item ?offset (&/$Item ?length (&/$End)))) ?values]
         ^MethodVisitor *writer* &/get-writer
         _ (compile ?text)
         :let [_ (doto *writer*
@@ -255,7 +255,7 @@
     (return nil)))
 
 (defn ^:private compile-text-index [compile ?values special-args]
-  (|do [:let [(&/$Cons ?text (&/$Cons ?part (&/$Cons ?start (&/$Nil)))) ?values]
+  (|do [:let [(&/$Item ?text (&/$Item ?part (&/$Item ?start (&/$End)))) ?values]
         ^MethodVisitor *writer* &/get-writer
         _ (compile ?text)
         :let [_ (doto *writer*
@@ -287,7 +287,7 @@
 
 (do-template [<name> <class> <method>]
   (defn <name> [compile ?values special-args]
-    (|do [:let [(&/$Cons ?text (&/$Nil)) ?values]
+    (|do [:let [(&/$Item ?text (&/$End)) ?values]
           ^MethodVisitor *writer* &/get-writer
           _ (compile ?text)
           :let [_ (doto *writer*
@@ -301,7 +301,7 @@
   )
 
 (defn ^:private compile-text-char [compile ?values special-args]
-  (|do [:let [(&/$Cons ?text (&/$Cons ?idx (&/$Nil))) ?values]
+  (|do [:let [(&/$Item ?text (&/$Item ?idx (&/$End))) ?values]
         ^MethodVisitor *writer* &/get-writer
         _ (compile ?text)
         :let [_ (doto *writer*
@@ -316,7 +316,7 @@
     (return nil)))
 
 (defn ^:private compile-io-log [compile ?values special-args]
-  (|do [:let [(&/$Cons ?x (&/$Nil)) ?values]
+  (|do [:let [(&/$Item ?x (&/$End)) ?values]
         ^MethodVisitor *writer* &/get-writer
         :let [_ (doto *writer*
                   (.visitFieldInsn Opcodes/GETSTATIC "java/lang/System" "out" "Ljava/io/PrintStream;"))]
@@ -327,7 +327,7 @@
     (return nil)))
 
 (defn ^:private compile-io-error [compile ?values special-args]
-  (|do [:let [(&/$Cons ?message (&/$Nil)) ?values]
+  (|do [:let [(&/$Item ?message (&/$End)) ?values]
         ^MethodVisitor *writer* &/get-writer
         :let [_ (doto *writer*
                   (.visitTypeInsn Opcodes/NEW "java/lang/Error")
@@ -340,7 +340,7 @@
     (return nil)))
 
 (defn ^:private compile-io-current-time [compile ?values special-args]
-  (|do [:let [(&/$Nil) ?values]
+  (|do [:let [(&/$End) ?values]
         ^MethodVisitor *writer* &/get-writer
         :let [_ (doto *writer*
                   (.visitMethodInsn Opcodes/INVOKESTATIC "java/lang/System" "currentTimeMillis" "()J")
@@ -348,7 +348,7 @@
     (return nil)))
 
 (defn ^:private compile-syntax-char-case! [compile ?values ?patterns]
-  (|do [:let [(&/$Cons ?input (&/$Cons ?else ?matches)) ?values]
+  (|do [:let [(&/$Item ?input (&/$Item ?else ?matches)) ?values]
         ^MethodVisitor *writer* &/get-writer
         :let [pattern-labels (&/|map (fn [_] (new Label)) ?patterns)
               matched-patterns (&/fold (fn [matches chars+label]
diff --git a/lux-bootstrapper/src/lux/compiler/jvm/proc/host.clj b/lux-bootstrapper/src/lux/compiler/jvm/proc/host.clj
index a1039f0b3..a455be83a 100644
--- a/lux-bootstrapper/src/lux/compiler/jvm/proc/host.clj
+++ b/lux-bootstrapper/src/lux/compiler/jvm/proc/host.clj
@@ -50,28 +50,28 @@
     (if (&type/type= &type/Any *type*)
       (.visitLdcInsn *writer* &/unit-tag)
       (|case *type*
-        (&/$Primitive "boolean" (&/$Nil))
+        (&/$Primitive "boolean" (&/$End))
         (.visitMethodInsn *writer* Opcodes/INVOKESTATIC (&host-generics/->bytecode-class-name boolean-class) "valueOf" (str "(Z)" (&host-generics/->type-signature boolean-class)))
         
-        (&/$Primitive "byte" (&/$Nil))
+        (&/$Primitive "byte" (&/$End))
         (.visitMethodInsn *writer* Opcodes/INVOKESTATIC (&host-generics/->bytecode-class-name byte-class) "valueOf" (str "(B)" (&host-generics/->type-signature byte-class)))
 
-        (&/$Primitive "short" (&/$Nil))
+        (&/$Primitive "short" (&/$End))
         (.visitMethodInsn *writer* Opcodes/INVOKESTATIC (&host-generics/->bytecode-class-name short-class) "valueOf" (str "(S)" (&host-generics/->type-signature short-class)))
 
-        (&/$Primitive "int" (&/$Nil))
+        (&/$Primitive "int" (&/$End))
         (.visitMethodInsn *writer* Opcodes/INVOKESTATIC (&host-generics/->bytecode-class-name int-class) "valueOf" (str "(I)" (&host-generics/->type-signature int-class)))
 
-        (&/$Primitive "long" (&/$Nil))
+        (&/$Primitive "long" (&/$End))
         (.visitMethodInsn *writer* Opcodes/INVOKESTATIC (&host-generics/->bytecode-class-name long-class) "valueOf" (str "(J)" (&host-generics/->type-signature long-class)))
 
-        (&/$Primitive "float" (&/$Nil))
+        (&/$Primitive "float" (&/$End))
         (.visitMethodInsn *writer* Opcodes/INVOKESTATIC (&host-generics/->bytecode-class-name float-class) "valueOf" (str "(F)" (&host-generics/->type-signature float-class)))
 
-        (&/$Primitive "double" (&/$Nil))
+        (&/$Primitive "double" (&/$End))
         (.visitMethodInsn *writer* Opcodes/INVOKESTATIC (&host-generics/->bytecode-class-name double-class) "valueOf" (str "(D)" (&host-generics/->type-signature double-class)))
 
-        (&/$Primitive "char" (&/$Nil))
+        (&/$Primitive "char" (&/$End))
         (.visitMethodInsn *writer* Opcodes/INVOKESTATIC (&host-generics/->bytecode-class-name char-class) "valueOf" (str "(C)" (&host-generics/->type-signature char-class)))
         
         (&/$Primitive _ _)
@@ -122,45 +122,45 @@
 
 (defn ^:private compile-method-return [^MethodVisitor writer output]
   (|case output
-    (&/$GenericClass "void" (&/$Nil))
+    (&/$GenericClass "void" (&/$End))
     (.visitInsn writer Opcodes/RETURN)
     
-    (&/$GenericClass "boolean" (&/$Nil))
+    (&/$GenericClass "boolean" (&/$End))
     (doto writer
       &&/unwrap-boolean
       (.visitInsn Opcodes/IRETURN))
     
-    (&/$GenericClass "byte" (&/$Nil))
+    (&/$GenericClass "byte" (&/$End))
     (doto writer
       &&/unwrap-byte
       (.visitInsn Opcodes/IRETURN))
     
-    (&/$GenericClass "short" (&/$Nil))
+    (&/$GenericClass "short" (&/$End))
     (doto writer
       &&/unwrap-short
       (.visitInsn Opcodes/IRETURN))
     
-    (&/$GenericClass "int" (&/$Nil))
+    (&/$GenericClass "int" (&/$End))
     (doto writer
       &&/unwrap-int
       (.visitInsn Opcodes/IRETURN))
     
-    (&/$GenericClass "long" (&/$Nil))
+    (&/$GenericClass "long" (&/$End))
     (doto writer
       &&/unwrap-long
       (.visitInsn Opcodes/LRETURN))
     
-    (&/$GenericClass "float" (&/$Nil))
+    (&/$GenericClass "float" (&/$End))
     (doto writer
       &&/unwrap-float
       (.visitInsn Opcodes/FRETURN))
     
-    (&/$GenericClass "double" (&/$Nil))
+    (&/$GenericClass "double" (&/$End))
     (doto writer
       &&/unwrap-double
       (.visitInsn Opcodes/DRETURN))
     
-    (&/$GenericClass "char" (&/$Nil))
+    (&/$GenericClass "char" (&/$End))
     (doto writer
       &&/unwrap-char
       (.visitInsn Opcodes/IRETURN))
@@ -230,15 +230,15 @@
   "(-> Int (List GenericClass) MethodVisitor (Lux (List FrameTag)))"
   [idx inputs method-visitor]
   (|case inputs
-    (&/$Nil)
-    (return &/$Nil)
+    (&/$End)
+    (return &/$End)
     
-    (&/$Cons input inputs*)
+    (&/$Item input inputs*)
     (|do [[_ outputs*] (&/fold% (fn [idx+outputs input]
                                   (|do [:let [[_idx _outputs] idx+outputs]
                                         [idx* output] (prepare-method-input _idx input method-visitor)]
-                                    (return (&/T [idx* (&/$Cons output _outputs)]))))
-                                (&/T [idx &/$Nil])
+                                    (return (&/T [idx* (&/$Item output _outputs)]))))
+                                (&/T [idx &/$End])
                                 inputs)]
       (return (&/list-join (&/|reverse outputs*))))
     ))
@@ -445,7 +445,7 @@
   "(-> (List FieldAnalysis) (List [Text GenericClass Analysis]))"
   [fields]
   (&/fold &/|++
-          &/$Nil
+          &/$End
           (&/|map (fn [field]
                     (|case field
                       (&/$ConstantFieldSyntax ?name ?anns ?gclass ?value)
@@ -461,7 +461,7 @@
   (|do [module &/get-module-name
         [file-name line column] &/location
         :let [[?name ?params] class-decl
-              class-signature (&host-generics/gclass-decl->signature class-decl (&/$Cons ?super-class ?interfaces))
+              class-signature (&host-generics/gclass-decl->signature class-decl (&/$Item ?super-class ?interfaces))
               full-name (str module "/" ?name)
               super-class* (&host-generics/->bytecode-class-name (&host-generics/super-class-name ?super-class))
               =class (doto (new ClassWriter ClassWriter/COMPUTE_MAXS)
@@ -513,7 +513,7 @@
 
 (do-template [<name> <op> <unwrap> <wrap>]
   (defn <name> [compile _?value special-args]
-    (|do [:let [(&/$Cons ?value (&/$Nil)) _?value]
+    (|do [:let [(&/$Item ?value (&/$End)) _?value]
           ^MethodVisitor *writer* &/get-writer
           _ (compile ?value)
           :let [_ (doto *writer*
@@ -553,7 +553,7 @@
 
 (do-template [<name> <op> <wrap>]
   (defn <name> [compile _?value special-args]
-    (|do [:let [(&/$Cons ?value (&/$Nil)) _?value]
+    (|do [:let [(&/$Item ?value (&/$End)) _?value]
           ^MethodVisitor *writer* &/get-writer
           _ (compile ?value)
           :let [_ (doto *writer*
@@ -569,7 +569,7 @@
 
 (do-template [<name> <op> <unwrap-left> <unwrap-right> <wrap>]
   (defn <name> [compile ?values special-args]
-    (|do [:let [(&/$Cons ?x (&/$Cons ?y (&/$Nil))) ?values]
+    (|do [:let [(&/$Item ?x (&/$Item ?y (&/$End))) ?values]
           ^MethodVisitor *writer* &/get-writer
           _ (compile ?x)
           :let [_ (doto *writer*
@@ -599,7 +599,7 @@
 
 (do-template [<name> <opcode> <unwrap> <wrap>]
   (defn <name> [compile ?values special-args]
-    (|do [:let [(&/$Cons ?x (&/$Cons ?y (&/$Nil))) ?values]
+    (|do [:let [(&/$Item ?x (&/$Item ?y (&/$End))) ?values]
           ^MethodVisitor *writer* &/get-writer
           _ (compile ?x)
           :let [_ (doto *writer*
@@ -639,7 +639,7 @@
 
 (do-template [<name> <opcode> <unwrap>]
   (defn <name> [compile ?values special-args]
-    (|do [:let [(&/$Cons ?x (&/$Cons ?y (&/$Nil))) ?values]
+    (|do [:let [(&/$Item ?x (&/$Item ?y (&/$End))) ?values]
           ^MethodVisitor *writer* &/get-writer
           _ (compile ?x)
           :let [_ (doto *writer*
@@ -669,7 +669,7 @@
 
 (do-template [<name> <cmpcode> <cmp-output> <unwrap>]
   (defn <name> [compile ?values special-args]
-    (|do [:let [(&/$Cons ?x (&/$Cons ?y (&/$Nil))) ?values]
+    (|do [:let [(&/$Item ?x (&/$Item ?y (&/$End))) ?values]
           ^MethodVisitor *writer* &/get-writer
           _ (compile ?x)
           :let [_ (doto *writer*
@@ -705,8 +705,8 @@
 
 (do-template [<prim-type> <array-type> <new-name> <load-name> <load-op> <store-name> <store-op> <wrapper> <unwrapper>]
   (do (defn <new-name> [compile ?values special-args]
-        (|do [:let [(&/$Cons ?length (&/$Nil)) ?values
-                    ;; (&/$Nil) special-args
+        (|do [:let [(&/$Item ?length (&/$End)) ?values
+                    ;; (&/$End) special-args
                     ]
               ^MethodVisitor *writer* &/get-writer
               _ (compile ?length)
@@ -717,8 +717,8 @@
           (return nil)))
 
     (defn <load-name> [compile ?values special-args]
-      (|do [:let [(&/$Cons ?array (&/$Cons ?idx (&/$Nil))) ?values
-                  ;; (&/$Nil) special-args
+      (|do [:let [(&/$Item ?array (&/$Item ?idx (&/$End))) ?values
+                  ;; (&/$End) special-args
                   ]
             ^MethodVisitor *writer* &/get-writer
             _ (compile ?array)
@@ -733,8 +733,8 @@
         (return nil)))
 
     (defn <store-name> [compile ?values special-args]
-      (|do [:let [(&/$Cons ?array (&/$Cons ?idx (&/$Cons ?elem (&/$Nil)))) ?values
-                  ;; (&/$Nil) special-args
+      (|do [:let [(&/$Item ?array (&/$Item ?idx (&/$Item ?elem (&/$End)))) ?values
+                  ;; (&/$End) special-args
                   ]
             ^MethodVisitor *writer* &/get-writer
             _ (compile ?array)
@@ -762,8 +762,8 @@
   )
 
 (defn ^:private compile-jvm-anewarray [compile ?values special-args]
-  (|do [:let [(&/$Cons ?length (&/$Nil)) ?values
-              (&/$Cons ?gclass (&/$Cons type-env (&/$Nil))) special-args]
+  (|do [:let [(&/$Item ?length (&/$End)) ?values
+              (&/$Item ?gclass (&/$Item type-env (&/$End))) special-args]
         ^MethodVisitor *writer* &/get-writer
         _ (compile ?length)
         :let [_ (doto *writer*
@@ -773,8 +773,8 @@
     (return nil)))
 
 (defn ^:private compile-jvm-aaload [compile ?values special-args]
-  (|do [:let [(&/$Cons ?array (&/$Cons ?idx (&/$Nil))) ?values
-              ;; (&/$Nil) special-args
+  (|do [:let [(&/$Item ?array (&/$Item ?idx (&/$End))) ?values
+              ;; (&/$End) special-args
               ]
         ^MethodVisitor *writer* &/get-writer
         array-type (&host/->java-sig (&a/expr-type* ?array))
@@ -788,8 +788,8 @@
     (return nil)))
 
 (defn ^:private compile-jvm-aastore [compile ?values special-args]
-  (|do [:let [(&/$Cons ?array (&/$Cons ?idx (&/$Cons ?elem (&/$Nil)))) ?values
-              ;; (&/$Nil) special-args
+  (|do [:let [(&/$Item ?array (&/$Item ?idx (&/$Item ?elem (&/$End)))) ?values
+              ;; (&/$End) special-args
               ]
         ^MethodVisitor *writer* &/get-writer
         array-type (&host/->java-sig (&a/expr-type* ?array))
@@ -805,8 +805,8 @@
     (return nil)))
 
 (defn ^:private compile-jvm-arraylength [compile ?values special-args]
-  (|do [:let [(&/$Cons ?array (&/$Nil)) ?values
-              ;; (&/$Nil) special-args
+  (|do [:let [(&/$Item ?array (&/$End)) ?values
+              ;; (&/$End) special-args
               ]
         ^MethodVisitor *writer* &/get-writer
         array-type (&host/->java-sig (&a/expr-type* ?array))
@@ -819,15 +819,15 @@
     (return nil)))
 
 (defn ^:private compile-jvm-object-null [compile ?values special-args]
-  (|do [:let [;; (&/$Nil) ?values
-              (&/$Nil) special-args]
+  (|do [:let [;; (&/$End) ?values
+              (&/$End) special-args]
         ^MethodVisitor *writer* &/get-writer
         :let [_ (.visitInsn *writer* Opcodes/ACONST_NULL)]]
     (return nil)))
 
 (defn ^:private compile-jvm-object-null? [compile ?values special-args]
-  (|do [:let [(&/$Cons ?object (&/$Nil)) ?values
-              ;; (&/$Nil) special-args
+  (|do [:let [(&/$Item ?object (&/$End)) ?values
+              ;; (&/$End) special-args
               ]
         ^MethodVisitor *writer* &/get-writer
         _ (compile ?object)
@@ -843,8 +843,8 @@
     (return nil)))
 
 (defn compile-jvm-object-synchronized [compile ?values special-args]
-  (|do [:let [(&/$Cons ?monitor (&/$Cons ?expr (&/$Nil))) ?values
-              ;; (&/$Nil) special-args
+  (|do [:let [(&/$Item ?monitor (&/$Item ?expr (&/$End))) ?values
+              ;; (&/$End) special-args
               ]
         ^MethodVisitor *writer* &/get-writer
         _ (compile ?monitor)
@@ -858,8 +858,8 @@
     (return nil)))
 
 (defn ^:private compile-jvm-throw [compile ?values special-args]
-  (|do [:let [(&/$Cons ?ex (&/$Nil)) ?values
-              ;; (&/$Nil) special-args
+  (|do [:let [(&/$Item ?ex (&/$End)) ?values
+              ;; (&/$End) special-args
               ]
         ^MethodVisitor *writer* &/get-writer
         _ (compile ?ex)
@@ -867,8 +867,8 @@
     (return nil)))
 
 (defn ^:private compile-jvm-getstatic [compile ?values special-args]
-  (|do [:let [;; (&/$Nil) ?values
-              (&/$Cons ?class (&/$Cons ?field (&/$Cons ?output-type (&/$Nil)))) special-args]
+  (|do [:let [;; (&/$End) ?values
+              (&/$Item ?class (&/$Item ?field (&/$Item ?output-type (&/$End)))) special-args]
         ^MethodVisitor *writer* &/get-writer
         =output-type (&host/->java-sig ?output-type)
         :let [_ (doto *writer*
@@ -877,8 +877,8 @@
     (return nil)))
 
 (defn ^:private compile-jvm-getfield [compile ?values special-args]
-  (|do [:let [(&/$Cons ?object (&/$Nil)) ?values
-              (&/$Cons ?class (&/$Cons ?field (&/$Cons ?output-type (&/$Nil)))) special-args]
+  (|do [:let [(&/$Item ?object (&/$End)) ?values
+              (&/$Item ?class (&/$Item ?field (&/$Item ?output-type (&/$End)))) special-args]
         :let [class* (&host-generics/->bytecode-class-name (&host-type/as-obj ?class))]
         ^MethodVisitor *writer* &/get-writer
         _ (compile ?object)
@@ -890,8 +890,8 @@
     (return nil)))
 
 (defn ^:private compile-jvm-putstatic [compile ?values special-args]
-  (|do [:let [(&/$Cons ?value (&/$Nil)) ?values
-              (&/$Cons ?class (&/$Cons ?field (&/$Cons input-gclass (&/$Nil)))) special-args]
+  (|do [:let [(&/$Item ?value (&/$End)) ?values
+              (&/$Item ?class (&/$Item ?field (&/$Item input-gclass (&/$End)))) special-args]
         ^MethodVisitor *writer* &/get-writer
         _ (compile ?value)
         :let [=input-sig (&host-type/gclass->sig input-gclass)
@@ -902,8 +902,8 @@
     (return nil)))
 
 (defn ^:private compile-jvm-putfield [compile ?values special-args]
-  (|do [:let [(&/$Cons ?object (&/$Cons ?value (&/$Nil))) ?values
-              (&/$Cons ?class (&/$Cons ?field (&/$Cons input-gclass (&/$Cons ?input-type (&/$Nil))))) special-args]
+  (|do [:let [(&/$Item ?object (&/$Item ?value (&/$End))) ?values
+              (&/$Item ?class (&/$Item ?field (&/$Item input-gclass (&/$Item ?input-type (&/$End))))) special-args]
         :let [class* (&host-generics/->bytecode-class-name (&host-type/as-obj ?class))]
         ^MethodVisitor *writer* &/get-writer
         _ (compile ?object)
@@ -918,7 +918,7 @@
 
 (defn ^:private compile-jvm-invokestatic [compile ?values special-args]
   (|do [:let [?args ?values
-              (&/$Cons ?class (&/$Cons ?method (&/$Cons ?classes (&/$Cons ?output-type (&/$Cons ?gret (&/$Nil)))))) special-args]
+              (&/$Item ?class (&/$Item ?method (&/$Item ?classes (&/$Item ?output-type (&/$Item ?gret (&/$End)))))) special-args]
         ^MethodVisitor *writer* &/get-writer
         :let [method-sig (str "(" (&/fold str "" (&/|map &host-generics/->type-signature ?classes)) ")" (&host-type/principal-class ?gret))]
         _ (&/map2% (fn [class-name arg]
@@ -933,8 +933,8 @@
 
 (do-template [<name> <op>]
   (defn <name> [compile ?values special-args]
-    (|do [:let [(&/$Cons ?object ?args) ?values
-                (&/$Cons ?class (&/$Cons ?method (&/$Cons ?classes (&/$Cons ?output-type (&/$Cons ?gret (&/$Nil)))))) special-args]
+    (|do [:let [(&/$Item ?object ?args) ?values
+                (&/$Item ?class (&/$Item ?method (&/$Item ?classes (&/$Item ?output-type (&/$Item ?gret (&/$End)))))) special-args]
           :let [?class* (&host-generics/->bytecode-class-name (&host-type/as-obj ?class))]
           ^MethodVisitor *writer* &/get-writer
           :let [method-sig (str "(" (&/fold str "" (&/|map &host-generics/->type-signature ?classes)) ")" (&host-type/principal-class ?gret))]
@@ -958,7 +958,7 @@
 
 (defn ^:private compile-jvm-new [compile ?values special-args]
   (|do [:let [?args ?values
-              (&/$Cons ?class (&/$Cons ?classes (&/$Nil))) special-args]
+              (&/$Item ?class (&/$Item ?classes (&/$End))) special-args]
         ^MethodVisitor *writer* &/get-writer
         :let [init-sig (str "(" (&/fold str "" (&/|map &host-generics/->type-signature ?classes)) ")V")
               class* (&host-generics/->bytecode-class-name ?class)
@@ -976,7 +976,7 @@
     (return nil)))
 
 (defn ^:private compile-jvm-object-class [compile ?values special-args]
-  (|do [:let [(&/$Cons _class-name (&/$Cons ?output-type (&/$Nil))) special-args]
+  (|do [:let [(&/$Item _class-name (&/$Item ?output-type (&/$End))) special-args]
         ^MethodVisitor *writer* &/get-writer
         :let [_ (doto *writer*
                   (.visitLdcInsn _class-name)
@@ -985,8 +985,8 @@
     (return nil)))
 
 (defn ^:private compile-jvm-instanceof [compile ?values special-args]
-  (|do [:let [(&/$Cons object (&/$Nil)) ?values
-              (&/$Cons class (&/$Nil)) special-args]
+  (|do [:let [(&/$Item object (&/$End)) ?values
+              (&/$Item class (&/$End)) special-args]
         :let [class* (&host-generics/->bytecode-class-name class)]
         ^MethodVisitor *writer* &/get-writer
         _ (compile object)
diff --git a/lux-bootstrapper/src/lux/host.clj b/lux-bootstrapper/src/lux/host.clj
index eb1bcb41c..4d49a6262 100644
--- a/lux-bootstrapper/src/lux/host.clj
+++ b/lux-bootstrapper/src/lux/host.clj
@@ -42,7 +42,7 @@
   "(-> Type (, Int Type))"
   [type]
   (|case type
-    (&/$Primitive "#Array" (&/$Cons param (&/$Nil)))
+    (&/$Primitive "#Array" (&/$Item param (&/$End)))
     (|let [[count inner] (unfold-array param)]
       (&/T [(inc count) inner]))
 
@@ -170,7 +170,7 @@
   (str (&/normalize-name name) "_" (Long/toUnsignedString (hash name))))
 
 (defn location [scope]
-  (let [scope (&/$Cons (def-name (&/|head scope))
+  (let [scope (&/$Item (def-name (&/|head scope))
                        (&/|map &/normalize-name (&/|tail scope)))]
     (->> scope
          (&/|interpose "$")
@@ -185,35 +185,35 @@
 
 (defn dummy-value [^MethodVisitor writer class]
   (|case class
-    (&/$GenericClass "boolean" (&/$Nil))
+    (&/$GenericClass "boolean" (&/$End))
     (doto writer
       (.visitLdcInsn false))
     
-    (&/$GenericClass "byte" (&/$Nil))
+    (&/$GenericClass "byte" (&/$End))
     (doto writer
       (.visitLdcInsn (byte 0)))
     
-    (&/$GenericClass "short" (&/$Nil))
+    (&/$GenericClass "short" (&/$End))
     (doto writer
       (.visitLdcInsn (short 0)))
     
-    (&/$GenericClass "int" (&/$Nil))
+    (&/$GenericClass "int" (&/$End))
     (doto writer
       (.visitLdcInsn (int 0)))
     
-    (&/$GenericClass "long" (&/$Nil))
+    (&/$GenericClass "long" (&/$End))
     (doto writer
       (.visitLdcInsn (long 0)))
     
-    (&/$GenericClass "float" (&/$Nil))
+    (&/$GenericClass "float" (&/$End))
     (doto writer
       (.visitLdcInsn (float 0.0)))
     
-    (&/$GenericClass "double" (&/$Nil))
+    (&/$GenericClass "double" (&/$End))
     (doto writer
       (.visitLdcInsn (double 0.0)))
     
-    (&/$GenericClass "char" (&/$Nil))
+    (&/$GenericClass "char" (&/$End))
     (doto writer
       (.visitLdcInsn (char 0)))
 
@@ -223,45 +223,45 @@
 
 (defn ^:private dummy-return [^MethodVisitor writer output]
   (|case output
-    (&/$GenericClass "void" (&/$Nil))
+    (&/$GenericClass "void" (&/$End))
     (.visitInsn writer Opcodes/RETURN)
 
-    (&/$GenericClass "boolean" (&/$Nil))
+    (&/$GenericClass "boolean" (&/$End))
     (doto writer
       (dummy-value output)
       (.visitInsn Opcodes/IRETURN))
     
-    (&/$GenericClass "byte" (&/$Nil))
+    (&/$GenericClass "byte" (&/$End))
     (doto writer
       (dummy-value output)
       (.visitInsn Opcodes/IRETURN))
     
-    (&/$GenericClass "short" (&/$Nil))
+    (&/$GenericClass "short" (&/$End))
     (doto writer
       (dummy-value output)
       (.visitInsn Opcodes/IRETURN))
     
-    (&/$GenericClass "int" (&/$Nil))
+    (&/$GenericClass "int" (&/$End))
     (doto writer
       (dummy-value output)
       (.visitInsn Opcodes/IRETURN))
     
-    (&/$GenericClass "long" (&/$Nil))
+    (&/$GenericClass "long" (&/$End))
     (doto writer
       (dummy-value output)
       (.visitInsn Opcodes/LRETURN))
     
-    (&/$GenericClass "float" (&/$Nil))
+    (&/$GenericClass "float" (&/$End))
     (doto writer
       (dummy-value output)
       (.visitInsn Opcodes/FRETURN))
     
-    (&/$GenericClass "double" (&/$Nil))
+    (&/$GenericClass "double" (&/$End))
     (doto writer
       (dummy-value output)
       (.visitInsn Opcodes/DRETURN))
     
-    (&/$GenericClass "char" (&/$Nil))
+    (&/$GenericClass "char" (&/$End))
     (doto writer
       (dummy-value output)
       (.visitInsn Opcodes/IRETURN))
@@ -443,7 +443,7 @@
               dummy-full-name (str module "/" dummy-name)
               real-name (str (&host-generics/->class-name module) "." ?name)
               store-name (str (&host-generics/->class-name module) "." dummy-name)
-              class-signature (&host-generics/gclass-decl->signature class-decl (&/$Cons super-class interfaces))
+              class-signature (&host-generics/gclass-decl->signature class-decl (&/$Item super-class interfaces))
               =class (doto (new ClassWriter ClassWriter/COMPUTE_MAXS)
                        (.visit bytecode-version (+ Opcodes/ACC_PUBLIC Opcodes/ACC_SUPER)
                                dummy-full-name
diff --git a/lux-bootstrapper/src/lux/host/generics.clj b/lux-bootstrapper/src/lux/host/generics.clj
index 58986c100..a1795bb18 100644
--- a/lux-bootstrapper/src/lux/host/generics.clj
+++ b/lux-bootstrapper/src/lux/host/generics.clj
@@ -46,7 +46,7 @@
 (defn formal-type-parameter->signature [param]
   (|let [[pname pbounds] param]
     (|case pbounds
-      (&/$Nil)
+      (&/$End)
       pname
 
       _
diff --git a/lux-bootstrapper/src/lux/optimizer.clj b/lux-bootstrapper/src/lux/optimizer.clj
index c8c8af02f..5910d98db 100644
--- a/lux-bootstrapper/src/lux/optimizer.clj
+++ b/lux-bootstrapper/src/lux/optimizer.clj
@@ -209,12 +209,12 @@
     (|case _sub-tests
       ;; An empty tuple corresponds to unit, which cannot be tested in
       ;; any meaningful way, so it's just popped.
-      (&/$Nil)
+      (&/$End)
       (&/|list $PopPM)
 
       ;; A tuple of a single element is equivalent to the element
       ;; itself, to the element's PM is generated.
-      (&/$Cons _only-test (&/$Nil))
+      (&/$Item _only-test (&/$End))
       (transform-pm* _only-test)
 
       ;; Single tuple PM features the tests of each tuple member
@@ -227,7 +227,7 @@
       (|let [tuple-size (&/|length _sub-tests)]
         (&/|++ (&/flat-map (fn [idx+test*]
                              (|let [[idx test*] idx+test*]
-                               (&/$Cons ($TuplePM (if (< idx (dec tuple-size))
+                               (&/$Item ($TuplePM (if (< idx (dec tuple-size))
                                                     (&/$Left idx)
                                                     (&/$Right idx)))
                                         (transform-pm* test*))))
@@ -246,7 +246,7 @@
 ;; This function cleans them all up, to avoid wasteful computation later.
 (defn ^:private clean-unnecessary-pops [steps]
   (|case steps
-    (&/$Cons ($PopPM) _steps)
+    (&/$Item ($PopPM) _steps)
     (clean-unnecessary-pops _steps)
 
     _
@@ -442,14 +442,14 @@
 ;; For example: (2 3 4 5 6 7 8), instead of (8 7 6 5 4 3 2)
 (defn ^:private adjust-register-indexes* [offset var-table]
   (|case var-table
-    (&/$Nil)
+    (&/$End)
     (&/|list)
 
-    (&/$Cons [_idx _used?] _tail)
+    (&/$Item [_idx _used?] _tail)
     (if _used?
-      (&/$Cons (&/T [_idx (- _idx offset)])
+      (&/$Item (&/T [_idx (- _idx offset)])
                (adjust-register-indexes* offset _tail))
-      (&/$Cons (&/T [_idx -1])
+      (&/$Item (&/T [_idx -1])
                (adjust-register-indexes* (inc offset) _tail))
       )))
 
@@ -576,10 +576,10 @@
          pms (&/|map &/|first pms+bodies)
          bodies (&/|map &/|second pms+bodies)]
     (|case (&/|reverse pms)
-      (&/$Nil)
+      (&/$End)
       (assert false)
 
-      (&/$Cons _head-pm _tail-pms)
+      (&/$Item _head-pm _tail-pms)
       (&/T [(&/fold fuse-pms _head-pm _tail-pms)
             bodies])
       )))
@@ -679,7 +679,7 @@
       ($apply [meta-0 ($var (&/$Local 0))] args)
       (if own-body?
         (&/T [meta ($apply (&/T [meta-0 ($var (&/$Local 0))])
-                           (&/$Cons (&/T [meta-0 ($var (&/$Local 1))])
+                           (&/$Item (&/T [meta-0 ($var (&/$Local 1))])
                                     (&/|map (partial shift-function-body old-scope new-scope own-body?) args)))])
         (&/T [meta ($apply (&/T [meta-0 ($var (&/$Local 0))])
                            (&/|map (partial shift-function-body old-scope new-scope own-body?) args))]))
@@ -692,7 +692,7 @@
       (if own-body?
         source
         (|case scope
-          (&/$Cons _ (&/$Cons _ (&/$Nil)))
+          (&/$Item _ (&/$Item _ (&/$End)))
           source
 
           _
@@ -750,10 +750,10 @@
   (loop [current-idx 0
          pms pms]
     (|case pms
-      (&/$Nil)
+      (&/$End)
       &/$None
       
-      (&/$Cons _pm _pms)
+      (&/$Item _pm _pms)
       (|case _pm
         (&a-case/$NoTestAC)
         (recur (inc current-idx)
@@ -768,7 +768,7 @@
         (&a-case/$TupleTestAC _sub-tests)
         (let [sub-path (record-read-path _sub-tests member-idx)]
           (if (not (&/|empty? sub-path))
-            (&/$Cons (&/T [current-idx (&/|empty? _pms)]) sub-path)
+            (&/$Item (&/T [current-idx (&/|empty? _pms)]) sub-path)
             (recur (inc current-idx)
                    _pms)
             ))
@@ -813,10 +813,10 @@
       ($ann _value-expr _type-expr)
       (&/T [meta ($ann (optimize-iter arity _value-expr) _type-expr)])
 
-      ($proc ["lux" "syntax char case!"] (&/$Cons ?input (&/$Cons ?else ?matches)) ?special-args)
+      ($proc ["lux" "syntax char case!"] (&/$Item ?input (&/$Item ?else ?matches)) ?special-args)
       (&/T [meta ($proc (&/T ["lux" "syntax char case!"])
-                        (&/$Cons ?input
-                                 (&/$Cons (optimize-iter arity ?else)
+                        (&/$Item ?input
+                                 (&/$Item (optimize-iter arity ?else)
                                           (&/|map (partial optimize-iter arity)
                                                   ?matches)))
                         ?special-args)])
@@ -858,7 +858,7 @@
       (or (contains-self-reference? func)
           (&/fold stepwise-test false args))
       
-      ($proc ["lux" "syntax char case!"] (&/$Cons ?input (&/$Cons ?else ?matches)) ?special-args)
+      ($proc ["lux" "syntax char case!"] (&/$Item ?input (&/$Item ?else ?matches)) ?special-args)
       (or (contains-self-reference? ?input)
           (contains-self-reference? ?else)
           (&/fold stepwise-test false ?matches))
@@ -1064,33 +1064,33 @@
           (|case branches
             ;; The pattern for a let-expression is a single branch,
             ;; tying the value to a register.
-            (&/$Cons [(&a-case/$StoreTestAC _register) _body] (&/$Nil))
+            (&/$Item [(&a-case/$StoreTestAC _register) _body] (&/$End))
             (&/T [meta ($let (pass-0 top-level-func? value) _register (pass-0 top-level-func? _body))])
 
-            (&/$Cons [(&a-case/$BitTestAC true) _then]
-                     (&/$Cons [(&a-case/$BitTestAC false) _else]
-                              (&/$Nil)))
+            (&/$Item [(&a-case/$BitTestAC true) _then]
+                     (&/$Item [(&a-case/$BitTestAC false) _else]
+                              (&/$End)))
             (&/T [meta ($if (pass-0 top-level-func? value) (pass-0 top-level-func? _then) (pass-0 top-level-func? _else))])
 
-            (&/$Cons [(&a-case/$BitTestAC true) _then]
-                     (&/$Cons [(&a-case/$NoTestAC false) _else]
-                              (&/$Nil)))
+            (&/$Item [(&a-case/$BitTestAC true) _then]
+                     (&/$Item [(&a-case/$NoTestAC false) _else]
+                              (&/$End)))
             (&/T [meta ($if (pass-0 top-level-func? value) (pass-0 top-level-func? _then) (pass-0 top-level-func? _else))])
 
-            (&/$Cons [(&a-case/$BitTestAC false) _else]
-                     (&/$Cons [(&a-case/$BitTestAC true) _then]
-                              (&/$Nil)))
+            (&/$Item [(&a-case/$BitTestAC false) _else]
+                     (&/$Item [(&a-case/$BitTestAC true) _then]
+                              (&/$End)))
             (&/T [meta ($if (pass-0 top-level-func? value) (pass-0 top-level-func? _then) (pass-0 top-level-func? _else))])
 
-            (&/$Cons [(&a-case/$BitTestAC false) _else]
-                     (&/$Cons [(&a-case/$NoTestAC) _then]
-                              (&/$Nil)))
+            (&/$Item [(&a-case/$BitTestAC false) _else]
+                     (&/$Item [(&a-case/$NoTestAC) _then]
+                              (&/$End)))
             (&/T [meta ($if (pass-0 top-level-func? value) (pass-0 top-level-func? _then) (pass-0 top-level-func? _else))])
 
             ;; The pattern for a record-get is a single branch, with a
             ;; tuple pattern and a body corresponding to a
             ;; local-variable extracted from the tuple.
-            (&/$Cons [(&a-case/$TupleTestAC _sub-tests) [_ (&a/$var (&/$Local _member-idx))]] (&/$Nil))
+            (&/$Item [(&a-case/$TupleTestAC _sub-tests) [_ (&a/$var (&/$Local _member-idx))]] (&/$End))
             (|let [_path (record-read-path _sub-tests _member-idx)]
               (if (&/|empty? _path)
                 ;; If the path is empty, that means it was a
diff --git a/lux-bootstrapper/src/lux/parser.clj b/lux-bootstrapper/src/lux/parser.clj
index dd33129b8..5d409400e 100644
--- a/lux-bootstrapper/src/lux/parser.clj
+++ b/lux-bootstrapper/src/lux/parser.clj
@@ -16,11 +16,11 @@
       (if (or (.contains error base-uneven-record-error)
               (not (.contains error "[Parser Error]")))
         (&/$Left error)
-        (&/$Right (&/T [state &/$Nil])))
+        (&/$Right (&/T [state &/$End])))
 
       (&/$Right state* head)
       ((|do [tail (repeat% action)]
-         (return (&/$Cons head tail)))
+         (return (&/$Item head tail)))
        state*))))
 
 (do-template [<name> <close-tag> <description> <tag>]
@@ -29,7 +29,7 @@
           token &lexer/lex]
       (|case token
         [meta (<close-tag> _)]
-        (return (<tag> (&/fold &/|++ &/$Nil elems)))
+        (return (<tag> (&/fold &/|++ &/$End elems)))
         
         _
         (&/fail-with-loc (str "[Parser Error] Unbalanced " <description> "."))
@@ -42,7 +42,7 @@
 (defn ^:private parse-record [parse]
   (|do [elems* (repeat% parse)
         token &lexer/lex
-        :let [elems (&/fold &/|++ &/$Nil elems*)]]
+        :let [elems (&/fold &/|++ &/$End elems*)]]
     (|case token
       [meta (&lexer/$Close_Brace _)]
       (|do [_ (&/assert! (even? (&/|length elems))
@@ -59,10 +59,10 @@
         :let [[meta token*] token]]
     (|case token*
       (&lexer/$White_Space _)
-      (return &/$Nil)
+      (return &/$End)
 
       (&lexer/$Comment _)
-      (return &/$Nil)
+      (return &/$End)
       
       (&lexer/$Bit ?value)
       (return (&/|list (&/T [meta (&/$Bit (.equals ^String ?value "#1"))])))
diff --git a/lux-bootstrapper/src/lux/reader.clj b/lux-bootstrapper/src/lux/reader.clj
index 14914cc2e..63d4db9fb 100644
--- a/lux-bootstrapper/src/lux/reader.clj
+++ b/lux-bootstrapper/src/lux/reader.clj
@@ -14,10 +14,10 @@
 (defn- with-line [body]
   (fn [state]
     (|case (&/get$ &/$source state)
-      (&/$Nil)
+      (&/$End)
       ((&/fail-with-loc "[Reader Error] EOF") state)
       
-      (&/$Cons [[file-name line-num column-num] line]
+      (&/$Item [[file-name line-num column-num] line]
                more)
       (|case (body file-name line-num column-num line)
         ($No msg)
@@ -28,7 +28,7 @@
                  output)
 
         ($Yes output line*)
-        (return* (&/set$ &/$source (&/$Cons line* more) state)
+        (return* (&/set$ &/$source (&/$Item line* more) state)
                  output))
       )))
 
@@ -84,10 +84,10 @@
       (loop [prefix ""
              reader* reader]
         (|case reader*
-          (&/$Nil)
+          (&/$End)
           (&/$Left "[Reader Error] EOF")
 
-          (&/$Cons [[file-name line-num column-num] ^String line]
+          (&/$Item [[file-name line-num column-num] ^String line]
                    reader**)
           (if-let [^String match (re-find! regex column-num line)]
             (let [match-length (.length match)
@@ -97,7 +97,7 @@
                             (str prefix match))]
               (if (= column-num* (.length line))
                 (recur prefix* reader**)
-                (&/$Right (&/T [(&/$Cons (&/T [(&/T [file-name line-num column-num*]) line])
+                (&/$Right (&/T [(&/$Item (&/T [(&/T [file-name line-num column-num*]) line])
                                          reader**)
                                 (&/T [(&/T [file-name line-num column-num]) prefix*])]))))
             (&/$Left (str "[Reader Error] Pattern failed: " regex))))))))
@@ -138,8 +138,8 @@
                                    line]))
                            lines
                            (range (count lines)))]
-    (reduce (fn [tail head] (&/$Cons head tail))
-            &/$Nil
+    (reduce (fn [tail head] (&/$Item head tail))
+            &/$End
             (reverse indexed-lines))))
 
 (defn with-source [name content body]
diff --git a/lux-bootstrapper/src/lux/type.clj b/lux-bootstrapper/src/lux/type.clj
index 267b6d67b..6472a341d 100644
--- a/lux-bootstrapper/src/lux/type.clj
+++ b/lux-bootstrapper/src/lux/type.clj
@@ -12,10 +12,10 @@
 ;; [Utils]
 (defn |list? [xs]
   (|case xs
-    (&/$Nil)
+    (&/$End)
     true
 
-    (&/$Cons x xs*)
+    (&/$Item x xs*)
     (|list? xs*)
 
     _
@@ -23,21 +23,21 @@
 
 (def max-stack-size 256)
 
-(def empty-env &/$Nil)
+(def empty-env &/$End)
 
 (def I64 (&/$Named (&/T [&/prelude "I64"])
                    (&/$UnivQ empty-env
                              (&/$Primitive "#I64" (&/|list (&/$Parameter 1))))))
-(def Nat* (&/$Primitive &&host/nat-data-tag &/$Nil))
-(def Rev* (&/$Primitive &&host/rev-data-tag &/$Nil))
-(def Int* (&/$Primitive &&host/int-data-tag &/$Nil))
+(def Nat* (&/$Primitive &&host/nat-data-tag &/$End))
+(def Rev* (&/$Primitive &&host/rev-data-tag &/$End))
+(def Int* (&/$Primitive &&host/int-data-tag &/$End))
 
-(def Bit (&/$Named (&/T [&/prelude "Bit"]) (&/$Primitive "#Bit" &/$Nil)))
+(def Bit (&/$Named (&/T [&/prelude "Bit"]) (&/$Primitive "#Bit" &/$End)))
 (def Nat (&/$Named (&/T [&/prelude "Nat"]) (&/$Apply Nat* I64)))
 (def Rev (&/$Named (&/T [&/prelude "Rev"]) (&/$Apply Rev* I64)))
 (def Int (&/$Named (&/T [&/prelude "Int"]) (&/$Apply Int* I64)))
-(def Frac (&/$Named (&/T [&/prelude "Frac"]) (&/$Primitive "#Frac" &/$Nil)))
-(def Text (&/$Named (&/T [&/prelude "Text"]) (&/$Primitive "#Text" &/$Nil)))
+(def Frac (&/$Named (&/T [&/prelude "Frac"]) (&/$Primitive "#Frac" &/$End)))
+(def Text (&/$Named (&/T [&/prelude "Text"]) (&/$Primitive "#Text" &/$End)))
 (def Ident (&/$Named (&/T [&/prelude "Ident"]) (&/$Product Text Text)))
 
 (defn Array [elemT]
@@ -64,9 +64,9 @@
   (&/$Named (&/T [&/prelude "List"])
             (&/$UnivQ empty-env
                       (&/$Sum
-                       ;; lux;Nil
+                       ;; lux;End
                        Any
-                       ;; lux;Cons
+                       ;; lux;Item
                        (&/$Product (&/$Parameter 1)
                                    (&/$Apply (&/$Parameter 1)
                                              (&/$Parameter 0)))))))
@@ -172,7 +172,7 @@
 
 (def Macro
   (&/$Named (&/T [&/prelude "Macro"])
-            (&/$Primitive "#Macro" &/$Nil)))
+            (&/$Primitive "#Macro" &/$End)))
 
 (defn bound? [id]
   (fn [state]
@@ -357,21 +357,21 @@
   (|case type
     (&/$Function ?in ?out)
     (|let [[??out ?args] (unravel-fun ?out)]
-      (&/T [??out (&/$Cons ?in ?args)]))
+      (&/T [??out (&/$Item ?in ?args)]))
 
     _
-    (&/T [type &/$Nil])))
+    (&/T [type &/$End])))
 
 (defn ^:private unravel-app
   ([fun-type tail]
    (|case fun-type
      (&/$Apply ?arg ?func)
-     (unravel-app ?func (&/$Cons ?arg tail))
+     (unravel-app ?func (&/$Item ?arg tail))
 
      _
      (&/T [fun-type tail])))
   ([fun-type]
-   (unravel-app fun-type &/$Nil)))
+   (unravel-app fun-type &/$End)))
 
 (do-template [<tag> <flatten> <at> <desc>]
   (do (defn <flatten>
@@ -379,7 +379,7 @@
         [type]
         (|case type
           (<tag> left right)
-          (&/$Cons left (<flatten> right))
+          (&/$Item left (<flatten> right))
 
           _
           (&/|list type)))
@@ -411,10 +411,10 @@
     "(-> (List Type) Type)"
     [types]
     (|case (&/|reverse types)
-      (&/$Cons last prevs)
+      (&/$Item last prevs)
       (&/fold (fn [right left] (<ctor> left right)) last prevs)
 
-      (&/$Nil)
+      (&/$End)
       <unit>))
 
   Variant$ &/$Sum  Nothing
@@ -425,7 +425,7 @@
   (|case type
     (&/$Primitive name params)
     (|case params
-      (&/$Nil)
+      (&/$End)
       (str "(primitive " (pr-str name) ")")
 
       _
@@ -521,10 +521,10 @@
 (defn ^:private fp-get [k fixpoints]
   (|let [[e a] k]
     (|case fixpoints
-      (&/$Nil)
+      (&/$End)
       &/$None
 
-      (&/$Cons [[e* a*] v*] fixpoints*)
+      (&/$Item [[e* a*] v*] fixpoints*)
       (if (and (type= e e*)
                (type= a a*))
         (&/$Some v*)
@@ -532,7 +532,7 @@
       )))
 
 (defn ^:private fp-put [k v fixpoints]
-  (&/$Cons (&/T [k v]) fixpoints))
+  (&/$Item (&/T [k v]) fixpoints))
 
 (defn show-type+ [type]
   (|case type
@@ -573,7 +573,7 @@
     
     (&/$UnivQ ?local-env ?local-def)
     (|case ?local-env
-      (&/$Nil)
+      (&/$End)
       (&/$UnivQ env ?local-def)
 
       _
@@ -581,7 +581,7 @@
 
     (&/$ExQ ?local-env ?local-def)
     (|case ?local-env
-      (&/$Nil)
+      (&/$End)
       (&/$ExQ env ?local-def)
 
       _
@@ -606,14 +606,14 @@
   (|case type-fn
     (&/$UnivQ local-env local-def)
     (return (beta-reduce (->> local-env
-                              (&/$Cons param)
-                              (&/$Cons type-fn))
+                              (&/$Item param)
+                              (&/$Item type-fn))
                          local-def))
 
     (&/$ExQ local-env local-def)
     (return (beta-reduce (->> local-env
-                              (&/$Cons param)
-                              (&/$Cons type-fn))
+                              (&/$Item param)
+                              (&/$Item type-fn))
                          local-def))
 
     (&/$Apply A F)
@@ -635,7 +635,7 @@
     (&/fail-with-loc (str "[Type System] Not a type function:\n" (show-type type-fn) "\n"
                           "for arg: " (show-type param)))))
 
-(def ^:private init-fixpoints &/$Nil)
+(def ^:private init-fixpoints &/$End)
 
 (defn ^:private check* [fixpoints invariant?? expected actual]
   (if (clojure.lang.Util/identical expected actual)
@@ -710,7 +710,7 @@
 
             (&/$Left _)
             (|case F2
-              (&/$UnivQ (&/$Cons _) _)
+              (&/$UnivQ (&/$Item _) _)
               ((|do [actual* (apply-type F2 A2)]
                  (check* fixpoints invariant?? expected actual*))
                state)
@@ -910,7 +910,7 @@
     (if (>= size-types size-members)
       (&/T [size-members (&/|++ (&/|take (dec size-members) ?member-types)
                                 (&/|list (|case (->> ?member-types (&/|drop (dec size-members)) (&/|reverse))
-                                           (&/$Cons last prevs)
+                                           (&/$Item last prevs)
                                            (&/fold (fn [right left] (&/$Product left right))
                                                    last prevs))))])
       (&/T [size-types ?member-types])
@@ -919,13 +919,13 @@
 (do-template [<name> <zero> <plus>]
   (defn <name> [types]
     (|case (&/|reverse types)
-      (&/$Nil)
+      (&/$End)
       <zero>
 
-      (&/$Cons type (&/$Nil))
+      (&/$Item type (&/$End))
       type
 
-      (&/$Cons last prevs)
+      (&/$Item last prevs)
       (&/fold (fn [r l] (<plus> l r)) last prevs)))
 
   fold-prod Any &/$Product
diff --git a/lux-bootstrapper/src/lux/type/host.clj b/lux-bootstrapper/src/lux/type/host.clj
index dbf780a84..692062f50 100644
--- a/lux-bootstrapper/src/lux/type/host.clj
+++ b/lux-bootstrapper/src/lux/type/host.clj
@@ -86,17 +86,17 @@
              stack (&/|list)]
         (if-let [super-interface (some valid-sub? (.getInterfaces sub-class))]
           (if (= super-class super-interface)
-            (&/$Cons super-interface stack)
-            (recur super-interface (&/$Cons super-interface stack)))
+            (&/$Item super-interface stack)
+            (recur super-interface (&/$Item super-interface stack)))
           (if-let [super* (.getSuperclass sub-class)]
-            (recur super* (&/$Cons super* stack))
+            (recur super* (&/$Item super* stack))
             stack)))
       (loop [sub-class sub-class
              stack (&/|list)]
         (let [super* (.getSuperclass sub-class)]
           (if (= super* super-class)
-            (&/$Cons super* stack)
-            (recur super* (&/$Cons super* stack))))))))
+            (&/$Item super* stack)
+            (recur super* (&/$Item super* stack))))))))
 
 (defn ^:private trace-lineage
   "(-> Class Class (List Class))"
@@ -105,7 +105,7 @@
     (&/|list)
     (&/|reverse (trace-lineage* super-class sub-class))))
 
-(let [matcher (fn [m ^TypeVariable jt lt] (&/$Cons (&/T [(.getName jt) lt]) m))]
+(let [matcher (fn [m ^TypeVariable jt lt] (&/$Item (&/T [(.getName jt) lt]) m))]
   (defn ^:private match-params [sub-type-params params]
     (assert (and (= (&/|length sub-type-params) (&/|length params))
                  (&/|every? (partial instance? TypeVariable) sub-type-params)))
@@ -137,7 +137,7 @@
               Any
               (reduce (fn [inner _] (&/$Primitive array-data-tag (&/|list inner)))
                       (&/$Primitive base (try (-> (Class/forName base) .getTypeParameters
-                                                  seq count (repeat (&/$Primitive "java.lang.Object" &/$Nil))
+                                                  seq count (repeat (&/$Primitive "java.lang.Object" &/$End))
                                                   &/->list)
                                            (catch Exception e
                                              (&/|list))))
@@ -183,7 +183,7 @@
           (if (type= Any class-type)
             "V"
             (|case class-type
-              (&/$Primitive "#Array" (&/$Cons (&/$Primitive class-name _) (&/$Nil)))
+              (&/$Primitive "#Array" (&/$Item (&/$Primitive class-name _) (&/$End)))
               (str "[" (&host-generics/->type-signature class-name))
 
               (&/$Primitive class-name _)
@@ -357,7 +357,7 @@
   "(-> GenericType GenericClass)"
   [gtype]
   (cond (instance? Class gtype)
-        (&/$GenericClass (.getName ^Class gtype) &/$Nil)
+        (&/$GenericClass (.getName ^Class gtype) &/$End)
 
         (instance? GenericArrayType gtype)
         (&/$GenericArray (gtype->gclass (.getGenericComponentType ^GenericArrayType gtype)))
@@ -385,7 +385,7 @@
     "(-> GenericClass Text)"
     [gclass]
     (|case gclass
-      (&/$GenericClass gclass-name (&/$Nil))
+      (&/$GenericClass gclass-name (&/$End))
       (case gclass-name
         "void"    "V"
         "boolean" "Z"