Mo' updates, less problems.

34 files changed, 764 insertions, 601 deletions

diff --git a/stdlib/source/lux.lux b/stdlib/source/lux.lux
index 2b9d0b27e..de071c35a 100644
--- a/stdlib/source/lux.lux
+++ b/stdlib/source/lux.lux
@@ -4593,7 +4593,7 @@
     (return (list (` ((let [(^open ".") (~ struct)] (~ (identifier$ member))) (~+ args)))))
     
     _
-    (fail "Wrong syntax for ::")))
+    (fail "Wrong syntax for \")))
 
 (macro: #export (set@ tokens)
   {#.doc (text$ ($_ "lux text concat"
diff --git a/stdlib/source/lux/data/format/xml.lux b/stdlib/source/lux/data/format/xml.lux
index 3683e9e57..bee2d2983 100644
--- a/stdlib/source/lux/data/format/xml.lux
+++ b/stdlib/source/lux/data/format/xml.lux
@@ -71,7 +71,7 @@
 
 (def: xml_char^
   (Parser Text)
-  (<>.either (<text>.none_of ($_ text\compose "<>&'" text.double_quote))
+  (<>.either (<text>.none_of ($_ text\compose "<>&" text.double_quote))
              xml_escape_char^))
 
 (def: xml_identifier
@@ -134,7 +134,7 @@
   (Parser Text)
   (|> (<text>.not (<text>.this "--"))
       <text>.some
-      (<text>.enclosed ["<--" "-->"])
+      (<text>.enclosed ["<!--" "-->"])
       spaced^))
 
 (def: xml_header^
@@ -154,8 +154,8 @@
 
 (def: text^
   (Parser XML)
-  (|> (<>.either cdata^
-                 (..spaced^ (<text>.many xml_char^)))
+  (|> (..spaced^ (<text>.many xml_char^))
+      (<>.either cdata^)
       (<>\map (|>> #Text))))
 
 (def: null^
@@ -166,28 +166,33 @@
   (Parser XML)
   (|> (<>.rec
        (function (_ node^)
-         (<>.either text^
-                    (spaced^
-                     (do <>.monad
-                       [_ (<text>.this "<")
-                        tag (spaced^ tag^)
-                        attrs (spaced^ attrs^)
-                        #let [no_children^ (do <>.monad
-                                             [_ (<text>.this "/>")]
-                                             (wrap (#Node tag attrs (list))))
-                              with_children^ (do <>.monad
-                                               [_ (<text>.this ">")
-                                                children (<>.some node^)
-                                                _ (close_tag^ tag)]
-                                               (wrap (#Node tag attrs children)))]]
-                       (<>.either no_children^
-                                  with_children^))))))
-      ## This is put outside of the call to "rec" because comments
-      ## cannot be located inside of XML nodes.
-      ## This way, the comments can only be before or after the main document.
-      (<>.before (<>.some comment^))
+         (|> (spaced^
+              (do <>.monad
+                [_ (<text>.this "<")
+                 tag (spaced^ tag^)
+                 attrs (spaced^ attrs^)
+                 #let [no_children^ (do <>.monad
+                                      [_ (<text>.this "/>")]
+                                      (wrap (#Node tag attrs (list))))
+                       ## TODO: Find a way to make do without this hack. Without it, some POM files fail when parsing them in Aedifex. Something like this fails: <configuration> </configuration>
+                       alternative_no_children^ (do <>.monad
+                                                  [_ (<text>.this ">")
+                                                   _ (<>.some <text>.space)
+                                                   _ (..close_tag^ tag)]
+                                                  (wrap (#Node tag attrs (list))))
+                       with_children^ (do <>.monad
+                                        [_ (<text>.this ">")
+                                         children (<>.some node^)
+                                         _ (..close_tag^ tag)]
+                                        (wrap (#Node tag attrs children)))]]
+                ($_ <>.either
+                    no_children^
+                    alternative_no_children^
+                    with_children^)))
+             (<>.before (<>.some ..comment^))
+             (<>.after (<>.some ..comment^))
+             (<>.either text^))))
       (<>.before (<>.some ..null^))
-      (<>.after (<>.some comment^))
       (<>.after (<>.maybe xml_header^))))
 
 (def: read
diff --git a/stdlib/source/lux/target/lua.lux b/stdlib/source/lux/target/lua.lux
index be46169dd..c1bceb634 100644
--- a/stdlib/source/lux/target/lua.lux
+++ b/stdlib/source/lux/target/lua.lux
@@ -1,5 +1,8 @@
 (.module:
   [lux (#- Location Code int if cond function or and not let)
+   [abstract
+    [equivalence (#+ Equivalence)]
+    [hash (#+ Hash)]]
    [control
     [pipe (#+ case> cond> new>)]]
    [data
@@ -27,6 +30,18 @@
 (abstract: #export (Code brand)
   Text
 
+  (structure: #export equivalence
+    (All [brand] (Equivalence (Code brand)))
+
+    (def: (= reference subject)
+      (\ text.equivalence = (:representation reference) (:representation subject))))
+
+  (structure: #export hash
+    (All [brand] (Hash (Code brand)))
+
+    (def: &equivalence ..equivalence)
+    (def: hash (|>> :representation (\ text.hash hash))))
+
   (def: #export manual
     (-> Text Code)
     (|>> :abstraction))
@@ -225,6 +240,10 @@
         (local vars)
         (set vars value)))
 
+  (def: #export (local/1 var value)
+    (-> Var Expression Statement)
+    (:abstraction (format "local " (:representation var) " = " (:representation value) ..statement_suffix)))
+
   (def: #export (if test then! else!)
     (-> Expression Statement Statement Statement)
     (:abstraction (format "if " (:representation test)
@@ -280,15 +299,20 @@
         (text.enclose ["(" ")"])
         :abstraction))
 
-  (def: #export (function name args body!)
-    (-> Var (List Var) Statement Statement)
-    (:abstraction
-     (format "function " (:representation name)
-             (|> args
-                 ..locations
-                 (text.enclose ["(" ")"]))
-             (..nest (:representation body!))
-             text.new_line "end" ..statement_suffix)))
+  (template [<name> <code>]
+    [(def: #export (<name> name args body!)
+       (-> Var (List Var) Statement Statement)
+       (:abstraction
+        (format <code> " " (:representation name)
+                (|> args
+                    ..locations
+                    (text.enclose ["(" ")"]))
+                (..nest (:representation body!))
+                text.new_line "end" ..statement_suffix)))]
+
+    [function "function"]
+    [local_function "local function"]
+    )
 
   (def: #export break
     Statement
diff --git a/stdlib/source/lux/tool/compiler/language/lux/phase/extension/generation/lua/common.lux b/stdlib/source/lux/tool/compiler/language/lux/phase/extension/generation/lua/common.lux
index 2f1917de9..7d7ce2fbf 100644
--- a/stdlib/source/lux/tool/compiler/language/lux/phase/extension/generation/lua/common.lux
+++ b/stdlib/source/lux/tool/compiler/language/lux/phase/extension/generation/lua/common.lux
@@ -39,13 +39,13 @@
           (/.install "or" (binary (product.uncurry _.bit_or)))
           (/.install "xor" (binary (product.uncurry _.bit_xor)))
           (/.install "left-shift" (binary (product.uncurry _.bit_shl)))
-          (/.install "logical-right-shift" (binary (product.uncurry //runtime.i64//logic_right_shift)))
+          (/.install "right-shift" (binary (product.uncurry //runtime.i64//right_shift)))
           (/.install "=" (binary (product.uncurry _.=)))
           (/.install "+" (binary (product.uncurry _.+)))
           (/.install "-" (binary (product.uncurry _.-)))
           (/.install "<" (binary (product.uncurry _.<)))
           (/.install "*" (binary (product.uncurry _.*)))
-          (/.install "/" (binary (product.uncurry _./)))
+          (/.install "/" (binary (product.uncurry _.//)))
           (/.install "%" (binary (product.uncurry _.%)))
           (/.install "f64" (unary (_./ (_.float +1.0))))
           (/.install "char" (unary (!unary "string.char")))
@@ -97,8 +97,8 @@
 
 (def: (io//log! messageO)
   (Unary Expression)
-  (_.or (_.apply/* (list messageO) (_.var "print"))
-        //runtime.unit))
+  (|> (_.apply/* (list messageO) (_.var "print"))
+      (_.or //runtime.unit)))
 
 (def: io_procs
   Bundle
diff --git a/stdlib/source/lux/tool/compiler/language/lux/phase/generation/lua/case.lux b/stdlib/source/lux/tool/compiler/language/lux/phase/generation/lua/case.lux
index e6dad82e5..3c56c2dfa 100644
--- a/stdlib/source/lux/tool/compiler/language/lux/phase/generation/lua/case.lux
+++ b/stdlib/source/lux/tool/compiler/language/lux/phase/generation/lua/case.lux
@@ -3,7 +3,8 @@
    [abstract
     ["." monad (#+ do)]]
    [data
-    ["." text]
+    ["." text
+     ["%" format (#+ format)]]
     [collection
      ["." list ("#\." functor fold)]
      ["." set]]]
@@ -20,9 +21,10 @@
       ["#/." case]]
      ["/#" // #_
       ["#." synthesis (#+ Member Synthesis Path)]
+      ["#." generation]
       ["//#" /// #_
        [reference
-        [variable (#+ Register)]]
+        ["#." variable (#+ Register)]]
        ["#." phase ("#\." monad)]
        [meta
         [archive (#+ Archive)]]]]]]])
@@ -31,6 +33,10 @@
   (-> Register Var)
   (|>> (///reference.local //reference.system) :assume))
 
+(def: #export capture
+  (-> Register Var)
+  (|>> (///reference.foreign //reference.system) :assume))
+
 (def: #export (let generate archive [valueS register bodyS])
   (Generator [Synthesis Register Synthesis])
   (do ///////phase.monad
@@ -139,7 +145,7 @@
       (///////phase\wrap ..pop!)
 
       (#/////synthesis.Bind register)
-      (///////phase\wrap (_.let (list (..register register)) ..peek))
+      (///////phase\wrap (_.local/1 (..register register) ..peek))
 
       (#/////synthesis.Bit_Fork when thenP elseP)
       (do {! ///////phase.monad}
@@ -195,7 +201,7 @@
       (do ///////phase.monad
         [then! (recur thenP)]
         (///////phase\wrap ($_ _.then
-                               (_.let (list (..register register)) ..peek_and_pop)
+                               (_.local/1 (..register register) ..peek_and_pop)
                                then!)))
 
       (^template [<tag> <combinator>]
@@ -216,15 +222,34 @@
                        pattern_matching!)
               (_.statement (|> (_.var "error") (_.apply/* (list (_.string ////synthesis/case.pattern_matching_error)))))))))
 
+(def: #export dependencies
+  (-> Path (List Var))
+  (|>> ////synthesis/case.storage
+       (get@ #////synthesis/case.dependencies)
+       set.to_list
+       (list\map (function (_ variable)
+                   (.case variable
+                     (#///////variable.Local register)
+                     (..register register)
+                     
+                     (#///////variable.Foreign register)
+                     (..capture register))))))
+
 (def: #export (case generate archive [valueS pathP])
   (Generator [Synthesis Path])
   (do ///////phase.monad
     [initG (generate archive valueS)
-     pattern_matching! (pattern_matching generate archive pathP)]
-    (wrap (|> ($_ _.then
-                  (_.local (list @temp))
-                  (_.let (list @cursor) (_.array (list initG)))
-                  (_.let (list @savepoint) (_.array (list)))
-                  pattern_matching!)
-              (_.closure (list))
-              (_.apply/* (list))))))
+     [[case_module case_artifact] pattern_matching!] (/////generation.with_new_context archive
+                                                       (pattern_matching generate archive pathP))
+     #let [@case (_.var (///reference.artifact [case_module case_artifact]))
+           @dependencies+ (..dependencies (/////synthesis.path/seq (/////synthesis.path/then valueS)
+                                                                   pathP))
+           directive (_.function @case @dependencies+
+                       ($_ _.then
+                           (_.local (list @temp))
+                           (_.local/1 @cursor (_.array (list initG)))
+                           (_.local/1 @savepoint (_.array (list)))
+                           pattern_matching!))]
+     _ (/////generation.execute! directive)
+     _ (/////generation.save! (%.nat case_artifact) directive)]
+    (wrap (_.apply/* @dependencies+ @case))))
diff --git a/stdlib/source/lux/tool/compiler/language/lux/phase/generation/lua/function.lux b/stdlib/source/lux/tool/compiler/language/lux/phase/generation/lua/function.lux
index 7c07c8c6d..c7fe7f51c 100644
--- a/stdlib/source/lux/tool/compiler/language/lux/phase/generation/lua/function.lux
+++ b/stdlib/source/lux/tool/compiler/language/lux/phase/generation/lua/function.lux
@@ -6,6 +6,8 @@
     pipe]
    [data
     ["." product]
+    [text
+     ["%" format (#+ format)]]
     [collection
      ["." list ("#\." functor fold)]]]
    [target
@@ -37,23 +39,24 @@
   (-> Register Var)
   (|>> (///reference.foreign //reference.system) :assume))
 
-(def: (with_closure function_name inits function_definition)
-  (-> Text (List Expression) Statement (Operation Expression))
+(def: (with_closure function_name inits @function @args @body)
+  (-> Text (List Expression) Var (List Var) Statement (Operation Expression))
   (case inits
     #.Nil
     (do ///////phase.monad
-      [_ (/////generation.execute! function_definition)
+      [#let [function_definition (_.function @function @args @body)]
+       _ (/////generation.execute! function_definition)
        _ (/////generation.save! function_name function_definition)]
-      (wrap (|> (_.var function_name) (_.apply/* inits))))
+      (wrap (_.var function_name)))
 
     _
     (do {! ///////phase.monad}
-      [@closure (\ ! map _.var (/////generation.gensym "closure"))
-       #let [directive (_.function @closure
+      [#let [@closure (_.var (format function_name "_closure"))
+             directive (_.function @closure
                          (|> (list.enumeration inits)
                              (list\map (|>> product.left ..capture)))
                          ($_ _.then
-                             function_definition
+                             (_.local_function @function @args @body)
                              (_.return (_.var function_name))))]
        _ (/////generation.execute! directive)
        _ (/////generation.save! (_.code @closure) directive)]
@@ -77,35 +80,35 @@
            arityO (|> arity .int _.int)
            @num_args (_.var "num_args")
            @self (_.var function_name)
-           initialize_self! (_.let (list (//case.register 0)) @self)
+           initialize_self! (_.local/1 (//case.register 0) @self)
            initialize! (list\fold (.function (_ post pre!)
                                     ($_ _.then
                                         pre!
-                                        (_.let (list (..input post)) (_.nth (|> post inc .int _.int) @curried))))
+                                        (_.local/1 (..input post) (_.nth (|> post inc .int _.int) @curried))))
                                   initialize_self!
                                   (list.indices arity))
-           pack (|>> (list) _.apply/* (|> (_.var "table.pack")))
+           pack (|>> (list) _.array)
            unpack (|>> (list) _.apply/* (|> (_.var "table.unpack")))
            @var_args (_.var "...")]]
     (with_closure function_name closureO+
-      (_.function @self (list @var_args)
-        ($_ _.then
-            (_.let (list @curried) (pack @var_args))
-            (_.let (list @num_args) (_.the "n" @curried))
-            (_.cond (list [(|> @num_args (_.= (_.int +0)))
-                           (_.return @self)]
-                          [(|> @num_args (_.= arityO))
-                           ($_ _.then
-                               initialize!
-                               (_.return bodyO))]
-                          [(|> @num_args (_.> arityO))
-                           (let [arity_inputs (//runtime.array//sub (_.int +0) arityO @curried)
-                                 extra_inputs (//runtime.array//sub arityO @num_args @curried)]
-                             (_.return (|> @self
-                                           (_.apply/* (list (unpack arity_inputs)))
-                                           (_.apply/* (list (unpack extra_inputs))))))])
-                    ## (|> @num_args (_.< arityO))
-                    (_.return (_.closure (list @var_args)
-                                         (_.return (|> @self (_.apply/* (list (unpack (//runtime.array//concat @curried (pack @var_args))))))))))
-            )))
+      @self (list @var_args)
+      ($_ _.then
+          (_.local/1 @curried (pack @var_args))
+          (_.local/1 @num_args (_.length @curried))
+          (_.cond (list [(|> @num_args (_.= (_.int +0)))
+                         (_.return @self)]
+                        [(|> @num_args (_.= arityO))
+                         ($_ _.then
+                             initialize!
+                             (_.return bodyO))]
+                        [(|> @num_args (_.> arityO))
+                         (let [arity_inputs (//runtime.array//sub (_.int +0) arityO @curried)
+                               extra_inputs (//runtime.array//sub arityO @num_args @curried)]
+                           (_.return (|> @self
+                                         (_.apply/* (list (unpack arity_inputs)))
+                                         (_.apply/* (list (unpack extra_inputs))))))])
+                  ## (|> @num_args (_.< arityO))
+                  (_.return (_.closure (list @var_args)
+                                       (_.return (|> @self (_.apply/* (list (unpack (//runtime.array//concat @curried (pack @var_args))))))))))
+          ))
     ))
diff --git a/stdlib/source/lux/tool/compiler/language/lux/phase/generation/lua/loop.lux b/stdlib/source/lux/tool/compiler/language/lux/phase/generation/lua/loop.lux
index 817ba118a..b1b8a47cb 100644
--- a/stdlib/source/lux/tool/compiler/language/lux/phase/generation/lua/loop.lux
+++ b/stdlib/source/lux/tool/compiler/language/lux/phase/generation/lua/loop.lux
@@ -7,22 +7,25 @@
     [text
      ["%" format (#+ format)]]
     [collection
-     ["." list ("#\." functor)]]]
+     ["." list ("#\." functor)]
+     ["." set]]]
    [math
     [number
      ["n" nat]]]
    [target
-    ["_" lua (#+ Expression Var)]]]
+    ["_" lua (#+ Var Expression Statement)]]]
   ["." // #_
    [runtime (#+ Operation Phase Phase! Generator Generator!)]
    ["#." case]
-   ["///#" //// #_
-    [synthesis (#+ Scope Synthesis)]
-    ["#." generation]
+   ["/#" // #_
+    ["#." reference]
     ["//#" /// #_
-     ["#." phase]
-     [reference
-      [variable (#+ Register)]]]]])
+     ["."synthesis (#+ Scope Synthesis)]
+     ["#." generation]
+     ["//#" /// #_
+      ["#." phase]
+      [reference
+       [variable (#+ Register)]]]]]])
 
 (def: loop_name
   (-> Nat Var)
@@ -30,18 +33,49 @@
 
 (def: #export (scope generate archive [start initsS+ bodyS])
   (Generator (Scope Synthesis))
-  (do {! ///////phase.monad}
-    [@loop (\ ! map ..loop_name /////generation.next)
-     initsO+ (monad.map ! (generate archive) initsS+)
-     bodyO (/////generation.with_anchor @loop
-             (generate archive bodyS))
-     #let [directive (_.function @loop (|> initsS+
-                                           list.enumeration
-                                           (list\map (|>> product.left (n.+ start) //case.register)))
-                       (_.return bodyO))]
-     _ (/////generation.execute! directive)
-     _ (/////generation.save! (_.code @loop) directive)]
-    (wrap (_.apply/* initsO+ @loop))))
+  (case initsS+
+    ## function/false/non-independent loop
+    #.Nil
+    (generate archive bodyS)
+
+    ## true loop
+    _
+    (do {! ///////phase.monad}
+      [@loop (\ ! map ..loop_name /////generation.next)
+       initsO+ (monad.map ! (generate archive) initsS+)
+       [loop_name bodyO] (/////generation.with_new_context archive
+                           (do !
+                             [@loop (\ ! map (|>> ///reference.artifact _.var)
+                                       (/////generation.context archive))]
+                             (/////generation.with_anchor @loop
+                               (generate archive bodyS))))
+       #let [@loop (_.var (///reference.artifact loop_name))
+             locals (|> initsS+
+                        list.enumeration
+                        (list\map (|>> product.left (n.+ start) //case.register)))
+             [directive instantiation] (: [Statement Expression]
+                                          (case (|> (synthesis.path/then bodyS)
+                                                    //case.dependencies
+                                                    (set.from_list _.hash)
+                                                    (set.difference (set.from_list _.hash locals))
+                                                    set.to_list)
+                                            #.Nil
+                                            [(_.function @loop locals
+                                               (_.return bodyO))
+                                             @loop]
+
+                                            foreigns
+                                            (let [@context (_.var (format (///reference.artifact loop_name) "_context"))]
+                                              [(_.function @context foreigns
+                                                 ($_ _.then
+                                                     (<| (_.local_function @loop locals)
+                                                         (_.return bodyO))
+                                                     (_.return @loop)
+                                                     ))
+                                               (_.apply/* foreigns @context)])))]
+       _ (/////generation.execute! directive)
+       _ (/////generation.save! (_.code @loop) directive)]
+      (wrap (_.apply/* initsO+ instantiation)))))
 
 (def: #export (recur generate archive argsS+)
   (Generator (List Synthesis))
diff --git a/stdlib/source/lux/tool/compiler/language/lux/phase/generation/lua/runtime.lux b/stdlib/source/lux/tool/compiler/language/lux/phase/generation/lua/runtime.lux
index 72f8576f5..d7b0f1cd3 100644
--- a/stdlib/source/lux/tool/compiler/language/lux/phase/generation/lua/runtime.lux
+++ b/stdlib/source/lux/tool/compiler/language/lux/phase/generation/lua/runtime.lux
@@ -58,7 +58,8 @@
 (def: prefix
   "LuxRuntime")
 
-(def: #export unit (_.string /////synthesis.unit))
+(def: #export unit
+  (_.string /////synthesis.unit))
 
 (def: (flag value)
   (-> Bit Literal)
@@ -232,7 +233,7 @@
 (runtime: (array//concat left right)
   (with_vars [temp idx]
     (let [copy! (function (_ input output)
-                  (<| (_.for_step idx (_.int +1) (_.the "n" input) (_.int +1))
+                  (<| (_.for_step idx (_.int +1) (_.length input) (_.int +1))
                       (_.statement (|> (_.var "table.insert") (_.apply/* (list output (_.nth idx input)))))))]
       ($_ _.then
           (_.let (list temp) (_.array (list)))
@@ -277,7 +278,7 @@
       @lux//program_args
       ))
 
-(runtime: (i64//logic_right_shift param subject)
+(runtime: (i64//right_shift param subject)
   (let [mask (|> (_.int +1)
                  (_.bit_shl (_.- param (_.int +64)))
                  (_.- (_.int +1)))]
@@ -288,7 +289,7 @@
 (def: runtime//i64
   Statement
   ($_ _.then
-      @i64//logic_right_shift
+      @i64//right_shift
       ))
 
 (runtime: (text//index subject param start)
@@ -301,22 +302,16 @@
           (_.return (..some idx))))))
 
 (runtime: (text//clip text from to)
-  (with_vars [size]
-    ($_ _.then
-        (_.let (list size) (_.apply/* (list text) (_.var "string.len")))
-        (_.if (_.or (_.> size from)
-                    (_.> size to))
-          (_.return ..none)
-          (_.return (..some (_.apply/* (list text from to) (_.var "string.sub")))))
-        )))
+  (_.return (_.apply/* (list text from to) (_.var "string.sub"))))
 
 (runtime: (text//char idx text)
   (with_vars [char]
     ($_ _.then
         (_.let (list char) (_.apply/* (list text idx) (_.var "string.byte")))
         (_.if (_.= _.nil char)
-          (_.return ..none)
-          (_.return (..some char))))))
+          (_.statement (_.apply/* (list (_.string "[Lux Error] Cannot get char from text."))
+                                  (_.var "error")))
+          (_.return char)))))
 
 (def: runtime//text
   Statement
diff --git a/stdlib/source/lux/type/resource.lux b/stdlib/source/lux/type/resource.lux
index a6d60074b..07425c45b 100644
--- a/stdlib/source/lux/type/resource.lux
+++ b/stdlib/source/lux/type/resource.lux
@@ -9,8 +9,8 @@
     ["." io (#+ IO)]
     [concurrency
      ["." promise (#+ Promise)]]
-    ["p" parser
-     ["s" code (#+ Parser)]]]
+    ["<>" parser
+     ["<.>" code (#+ Parser)]]]
    [data
     ["." identity (#+ Identity)]
     ["." maybe]
@@ -80,25 +80,22 @@
   [async Promise  promise.monad  run_async lift_async]
   )
 
-(abstract: #export Ordered [])
+(abstract: #export Ordered Any)
 
-(abstract: #export Commutative [])
+(abstract: #export Commutative Any)
 
 (abstract: #export (Key mode key)
-  []
+  Any
 
   (template [<name> <mode>]
     [(def: <name>
-       (Ex [k] (-> [] (Key <mode> k)))
+       (Ex [k] (-> Any (Key <mode> k)))
        (|>> :abstraction))]
 
     [ordered_key     Ordered]
     [commutative_key Commutative]
     ))
 
-(type: #export OK (Key Ordered))
-(type: #export CK (Key Commutative))
-
 (abstract: #export (Res key value)
   value
 
@@ -138,21 +135,22 @@
 
 (def: indices
   (Parser (List Nat))
-  (s.tuple (loop [seen (set.new n.hash)]
-             (do {! p.monad}
-               [done? s.end?]
-               (if done?
-                 (wrap (list))
-                 (do !
-                   [head s.nat
-                    _ (p.assert (exception.construct index_cannot_be_repeated head)
-                                (not (set.member? seen head)))
-                    tail (recur (set.add head seen))]
-                   (wrap (list& head tail))))))))
+  (<code>.tuple (loop [seen (set.new n.hash)]
+                  (do {! <>.monad}
+                    [done? <code>.end?]
+                    (if done?
+                      (wrap (list))
+                      (do !
+                        [head <code>.nat
+                         _ (<>.assert (exception.construct ..index_cannot_be_repeated head)
+                                      (not (set.member? seen head)))
+                         tail (recur (set.add head seen))]
+                        (wrap (list& head tail))))))))
 
 (def: (no_op Monad<m>)
   (All [m] (-> (Monad m) (Linear m Any)))
-  (function (_ context) (\ Monad<m> wrap [context []])))
+  (function (_ context)
+    (\ Monad<m> wrap [context []])))
 
 (template [<name> <m> <monad>]
   [(syntax: #export (<name> {swaps ..indices})
@@ -174,8 +172,8 @@
                                             swaps)
                                 maybe.assume
                                 row.to_list)
-                  g!inputsT+ (list\map (|>> (~) ..CK (`)) g!inputs)
-                  g!outputsT+ (list\map (|>> (~) ..CK (`)) g!outputs)]]
+                  g!inputsT+ (list\map (|>> (~) (..Key ..Commutative) (`)) g!inputs)
+                  g!outputsT+ (list\map (|>> (~) (..Key ..Commutative) (`)) g!outputs)]]
            (wrap (list (` (: (All [(~+ g!inputs) (~ g!context)]
                                (Procedure (~! <m>)
                                           [(~+ g!inputsT+) (~ g!context)]
@@ -191,10 +189,10 @@
 
 (def: amount
   (Parser Nat)
-  (do p.monad
-    [raw s.nat
-     _ (p.assert (exception.construct ..amount_cannot_be_zero [])
-                 (n.> 0 raw))]
+  (do <>.monad
+    [raw <code>.nat
+     _ (<>.assert (exception.construct ..amount_cannot_be_zero [])
+                  (n.> 0 raw))]
     (wrap raw)))
 
 (template [<name> <m> <monad> <from> <to>]
diff --git a/stdlib/source/lux/type/unit.lux b/stdlib/source/lux/type/unit.lux
index 0a3d5c61a..b45e32c37 100644
--- a/stdlib/source/lux/type/unit.lux
+++ b/stdlib/source/lux/type/unit.lux
@@ -103,6 +103,7 @@
                      (primitive (~ (code.text (scale_name name))) [(~' u)])))
                 (` (structure: (~+ (|export|.format export)) (~ (code.local_identifier (format "@" name)))
                      (..Scale (~ g!scale))
+                     
                      (def: (~' scale)
                        (|>> ..out
                             (i.* (~ (code.int (.int numerator))))
@@ -165,17 +166,23 @@
 (unit: #export Litre)
 (unit: #export Second)
 
-(structure: #export equivalence (All [unit] (Equivalence (Qty unit)))
+(structure: #export equivalence
+  (All [unit] (Equivalence (Qty unit)))
+  
   (def: (= reference sample)
     (i.= (out reference) (out sample))))
 
-(structure: #export order (All [unit] (Order (Qty unit)))
+(structure: #export order
+  (All [unit] (Order (Qty unit)))
+  
   (def: &equivalence ..equivalence)
   
   (def: (< reference sample)
     (i.< (out reference) (out sample))))
 
-(structure: #export enum (All [unit] (Enum (Qty unit)))
+(structure: #export enum
+  (All [unit] (Enum (Qty unit)))
+  
   (def: &order ..order)
   (def: succ (|>> ..out inc ..in))
   (def: pred (|>> ..out dec ..in)))
diff --git a/stdlib/source/program/aedifex/artifact.lux b/stdlib/source/program/aedifex/artifact.lux
index 07b53157f..9e87988ea 100644
--- a/stdlib/source/program/aedifex/artifact.lux
+++ b/stdlib/source/program/aedifex/artifact.lux
@@ -68,12 +68,12 @@
       (text.split_all_with ..group_separator)
       (text.join_with separator)))
 
-(def: #export (uri artifact)
-  (-> Artifact URI)
+(def: #export (uri version artifact)
+  (-> Version Artifact URI)
   (let [/ uri.separator
         group (..directory / (get@ #group artifact))
         name (get@ #name artifact)
-        version (get@ #version artifact)
+        ## version (get@ #version artifact)
         identity (..identity artifact)]
     (%.format group / name / version / identity)))
 
diff --git a/stdlib/source/program/aedifex/artifact/versioning.lux b/stdlib/source/program/aedifex/artifact/versioning.lux
index 41b3179d3..dab943145 100644
--- a/stdlib/source/program/aedifex/artifact/versioning.lux
+++ b/stdlib/source/program/aedifex/artifact/versioning.lux
@@ -89,9 +89,10 @@
   (Parser Versioning)
   (<| (..sub ..<versioning>)
       ($_ <>.and
-          (<xml>.somewhere //snapshot.parser)
-          (<xml>.somewhere ..last_updated_parser)
-          (<| <xml>.somewhere
+          (<>.default #//snapshot.Local (<xml>.somewhere //snapshot.parser))
+          (<>.default instant.epoch (<xml>.somewhere ..last_updated_parser))
+          (<| (<>.default (list))
+              <xml>.somewhere
               (..sub ..<snapshot_versions>)
               (<>.some //snapshot/version.parser))
           )))
diff --git a/stdlib/source/program/aedifex/command/build.lux b/stdlib/source/program/aedifex/command/build.lux
index 7241b1de4..388a48c89 100644
--- a/stdlib/source/program/aedifex/command/build.lux
+++ b/stdlib/source/program/aedifex/command/build.lux
@@ -107,7 +107,7 @@
   (All [!] (-> (file.System !) Path Artifact Path))
   (let [/ (\ fs separator)]
     (|> artifact
-        ///local.uri
+        (///local.uri (get@ #///artifact.version artifact))
         (text.replace_all uri.separator /)
         (format home /))))
 
diff --git a/stdlib/source/program/aedifex/command/deploy.lux b/stdlib/source/program/aedifex/command/deploy.lux
index fe96055ef..758f87ab9 100644
--- a/stdlib/source/program/aedifex/command/deploy.lux
+++ b/stdlib/source/program/aedifex/command/deploy.lux
@@ -63,12 +63,13 @@
      _ (///dependency/deployment.one
         repository
         [artifact ///artifact/type.lux_library]
-        {#///package.origin (#///repository/origin.Remote "")
-         #///package.library [library
-                              (///dependency/status.verified library)]
-         #///package.pom [pom
-                          (|> pom
-                              (\ xml.codec encode)
-                              (\ encoding.utf8 encode)
-                              ///dependency/status.verified)]})]
+        (let [pom_data (|> pom
+                           (\ xml.codec encode)
+                           (\ encoding.utf8 encode))]
+          {#///package.origin (#///repository/origin.Remote "")
+           #///package.library [library
+                                (///dependency/status.verified library)]
+           #///package.pom [pom
+                            pom_data
+                            (///dependency/status.verified pom_data)]}))]
     (console.write_line //clean.success console)))
diff --git a/stdlib/source/program/aedifex/command/deps.lux b/stdlib/source/program/aedifex/command/deps.lux
index 71dffeec1..14b5d803f 100644
--- a/stdlib/source/program/aedifex/command/deps.lux
+++ b/stdlib/source/program/aedifex/command/deps.lux
@@ -3,13 +3,16 @@
    [abstract
     [monad (#+ do)]]
    [control
+    ["." exception]
     [concurrency
      ["." promise (#+ Promise)]]]
    [data
     [collection
      ["." set (#+ Set)]
      ["." list ("#\." fold)]
-     ["." dictionary]]]
+     ["." dictionary]]
+    [text
+     ["%" format (#+ format)]]]
    [world
     [program (#+ Program)]
     ["." file]
@@ -18,22 +21,39 @@
    ["#." clean]
    ["/#" // #_
     [command (#+ Command)]
-    [artifact (#+ Artifact)]
     [repository (#+ Repository)]
     ["#" profile]
     ["#." action (#+ Action)]
-    ["#." dependency #_
+    ["#." artifact (#+ Artifact)]
+    ["#." dependency (#+ Dependency)
      ["#/." resolution (#+ Resolution)]
      ["#/." deployment]]]])
 
+(def: %dependency
+  (%.Format Dependency)
+  (|>> (get@ #///dependency.artifact)
+       ///artifact.format
+       %.text))
+
 (def: #export (do! console local remotes profile)
   (-> (Console Promise) (Repository Promise) (List (Repository Promise)) (Command Resolution))
-  (do ///action.monad
+  (do promise.monad
     [#let [dependencies (set.to_list (get@ #///.dependencies profile))]
-     cache (///dependency/resolution.all (list local) dependencies ///dependency/resolution.empty)
-     resolution (///dependency/resolution.all remotes dependencies cache)
-     cached (|> (dictionary.keys cache)
-                (list\fold dictionary.remove resolution)
-                (///dependency/deployment.all local))
-     _ (console.write_line //clean.success console)]
-    (wrap resolution)))
+     [local_successes local_failures cache] (///dependency/resolution.all (list local) dependencies ///dependency/resolution.empty)
+     [remote_successes remote_failures resolution] (///dependency/resolution.all remotes dependencies cache)]
+    (do ///action.monad
+      [cached (|> (dictionary.keys cache)
+                  (list\fold dictionary.remove resolution)
+                  (///dependency/deployment.all local))
+       _ (console.write_line //clean.success console)
+       _ (console.write_line (exception.report
+                              ["Local successes" (exception.enumerate %dependency local_successes)]
+                              ["Local failures" (exception.enumerate %dependency local_failures)]
+                              ["Remote successes" (let [remote_successes (|> remote_successes
+                                                                             (set.from_list ///dependency.hash)
+                                                                             (set.difference (set.from_list ///dependency.hash local_successes))
+                                                                             set.to_list)]
+                                                    (exception.enumerate %dependency remote_successes))]
+                              ["Remote failures" (exception.enumerate %dependency remote_failures)])
+                             console)]
+      (wrap resolution))))
diff --git a/stdlib/source/program/aedifex/command/install.lux b/stdlib/source/program/aedifex/command/install.lux
index b051a4900..35ffcf72f 100644
--- a/stdlib/source/program/aedifex/command/install.lux
+++ b/stdlib/source/program/aedifex/command/install.lux
@@ -54,15 +54,17 @@
     (do ///action.monad
       [package (export.library system (set.to_list (get@ #/.sources profile)))
        pom (\ promise.monad wrap (///pom.write profile))
-       _ (///dependency/deployment.one repository [identity ///artifact/type.lux_library]
-                                       {#///package.origin (#///origin.Local "")
-                                        #///package.library (let [library (binary.run tar.writer package)]
-                                                              [library (///dependency/status.verified library)])
-                                        #///package.pom [pom
-                                                         (|> pom
-                                                             (\ xml.codec encode)
-                                                             (\ encoding.utf8 encode)
-                                                             ///dependency/status.verified)]})]
+       _ (///dependency/deployment.one repository
+                                       [identity ///artifact/type.lux_library]
+                                       (let [pom_data (|> pom
+                                                          (\ xml.codec encode)
+                                                          (\ encoding.utf8 encode))]
+                                         {#///package.origin (#///origin.Local "")
+                                          #///package.library (let [library (binary.run tar.writer package)]
+                                                                [library (///dependency/status.verified library)])
+                                          #///package.pom [pom
+                                                           pom_data
+                                                           (///dependency/status.verified pom_data)]}))]
       (console.write_line //clean.success console))
 
     _
diff --git a/stdlib/source/program/aedifex/dependency/deployment.lux b/stdlib/source/program/aedifex/dependency/deployment.lux
index 1f3e776a9..04b82d7e2 100644
--- a/stdlib/source/program/aedifex/dependency/deployment.lux
+++ b/stdlib/source/program/aedifex/dependency/deployment.lux
@@ -32,7 +32,11 @@
    ["#." package (#+ Package)]
    ["#." artifact (#+ Artifact)
     ["#/." type]
-    ["#/." extension (#+ Extension)]]
+    ["#/." extension (#+ Extension)]
+    ["#/." versioning]
+    ["#/." snapshot
+     ["#/." version (#+ Version)
+      ["#/." value]]]]
    ["#." metadata
     ["#/." artifact]
     ["#/." snapshot]]
@@ -42,9 +46,9 @@
    ["#." repository (#+ Repository)
     ["#/." origin]]])
 
-(def: (with_status repository [artifact type] [data status])
-  (-> (Repository Promise) Dependency [Binary Status] (Promise (Try Any)))
-  (let [artifact (format (///artifact.uri artifact)
+(def: (with_status repository version_template [artifact type] [data status])
+  (-> (Repository Promise) ///artifact.Version Dependency [Binary Status] (Promise (Try Any)))
+  (let [artifact (format (///artifact.uri version_template artifact)
                          (///artifact/extension.extension type))
         deploy_hash (: (All [h] (-> (Codec Text (Hash h)) Extension (Hash h) (Promise (Try Any))))
                        (function (_ codec extension hash)
@@ -91,29 +95,44 @@
 (def: #export (one repository [artifact type] package)
   (-> (Repository Promise) Dependency Package (Promise (Try Artifact)))
   (do {! promise.monad}
-    [now (promise.future instant.now)]
+    [now (promise.future instant.now)
+     #let [version_template (get@ #///artifact.version artifact)]]
     (do (try.with !)
-      [_ (with_status repository [artifact type] (get@ #///package.library package))
+      [_ (with_status repository version_template [artifact type] (get@ #///package.library package))
 
-       _ (let [[pom status] (get@ #///package.pom package)]
+       _ (let [[pom pom_data status] (get@ #///package.pom package)]
            (with_status repository
+             version_template
              [artifact ///artifact/type.pom]
-             [(|> pom (\ xml.codec encode) (\ encoding.utf8 encode))
+             [pom_data
               status]))
 
        snapshot (///metadata/snapshot.read repository artifact)
+       #let [snapshot (|> snapshot
+                          (update@ [#///metadata/snapshot.versioning #///artifact/versioning.snapshot]
+                                   (function (_ snapshot)
+                                     (case snapshot
+                                       #///artifact/snapshot.Local
+                                       #///artifact/snapshot.Local
+                                       
+                                       (#///artifact/snapshot.Remote [_ build])
+                                       (#///artifact/snapshot.Remote [now (inc build)]))))
+                          (set@ [#///metadata/snapshot.versioning #///artifact/versioning.last_updated] now))
+             versioning_snapshot (get@ [#///metadata/snapshot.versioning #///artifact/versioning.snapshot] snapshot)]
        _ (|> snapshot
-             (set@ [#///metadata/snapshot.versioning #///metadata/snapshot.time_stamp] now)
-             (update@ [#///metadata/snapshot.versioning #///metadata/snapshot.build] inc)
-             (set@ [#///metadata/snapshot.versioning #///metadata/snapshot.snapshot]
-                   (list\compose (..artifacts type (product.right (get@ #///package.library package)))
-                                 (..artifacts ///artifact/type.pom (product.right (get@ #///package.pom package)))))
+             (set@ [#///metadata/snapshot.versioning #///artifact/versioning.versions]
+                   (list {#///artifact/snapshot/version.extension type
+                          #///artifact/snapshot/version.value (///artifact/snapshot/version/value.format
+                                                               {#///artifact/snapshot/version/value.version version_template
+                                                                #///artifact/snapshot/version/value.snapshot versioning_snapshot})
+                          #///artifact/snapshot/version.updated now}))
+             ## (set@ [#///metadata/snapshot.versioning #///artifact/versioning.snapshot]
+             ##       (list\compose (..artifacts type (product.right (get@ #///package.library package)))
+             ##                     (..artifacts ///artifact/type.pom (product.right (get@ #///package.pom package)))))
              (///metadata/snapshot.write repository artifact))
-
        project (///metadata/artifact.read repository artifact)
-       #let [version (get@ #///artifact.version artifact)]
        _ (|> project
-             (set@ #///metadata/artifact.versions (list version))
+             (set@ #///metadata/artifact.versions (list version_template))
              (set@ #///metadata/artifact.last_updated now)
              (///metadata/artifact.write repository artifact))]
       (wrap artifact))))
diff --git a/stdlib/source/program/aedifex/dependency/resolution.lux b/stdlib/source/program/aedifex/dependency/resolution.lux
index e6b24b152..1be540298 100644
--- a/stdlib/source/program/aedifex/dependency/resolution.lux
+++ b/stdlib/source/program/aedifex/dependency/resolution.lux
@@ -1,12 +1,13 @@
 (.module:
   [lux (#- Name)
+   ["." debug]
    ["." host (#+ import:)]
    [abstract
     [codec (#+ Codec)]
     [equivalence (#+ Equivalence)]
     [monad (#+ Monad do)]]
    [control
-    ["." try (#+ Try)]
+    ["." try (#+ Try) ("#\." functor)]
     ["." exception (#+ Exception exception:)]
     ["<>" parser
      ["<.>" xml (#+ Parser)]]
@@ -16,14 +17,15 @@
     ["." binary (#+ Binary)]
     ["." name]
     ["." maybe]
-    [text
+    ["." text
      ["%" format (#+ format)]
      ["." encoding]]
     [format
      ["." xml (#+ Tag XML)]]
     [collection
      ["." dictionary (#+ Dictionary)]
-     ["." set]]]
+     ["." set]
+     ["." list ("#\." functor monoid)]]]
    [math
     [number
      ["n" nat]
@@ -38,11 +40,17 @@
     ["#." hash (#+ Hash SHA-1 MD5)]
     ["#." pom]
     ["#." package (#+ Package)]
-    ["#." artifact (#+ Artifact)
-     ["#/." extension (#+ Extension)]]
+    ["#." artifact (#+ Version Artifact)
+     ["#/." extension (#+ Extension)]
+     ["#/." versioning]
+     ["." snapshot
+      [version
+       ["." value]]]]
     ["#." repository (#+ Repository)
      ["#/." remote (#+ Address)]
-     ["#/." origin (#+ Origin)]]]])
+     ["#/." origin (#+ Origin)]]
+    ["#." metadata
+     ["#/." snapshot]]]])
 
 (template [<name>]
   [(exception: #export (<name> {artifact Artifact} {extension Extension} {hash Text})
@@ -55,19 +63,30 @@
   [md5_does_not_match]
   )
 
-(def: (verified_hash library repository artifact extension hash codec exception)
+(import: java/lang/String
+  ["#::."
+   (trim [] java/lang/String)])
+
+(def: (verified_hash library repository version_template artifact extension hash codec exception)
   (All [h]
-    (-> Binary (Repository Promise) Artifact Extension
+    (-> Binary (Repository Promise) Version Artifact Extension
         (-> Binary (Hash h)) (Codec Text (Hash h))
         (Exception [Artifact Extension Text])
         (Promise (Try (Maybe (Hash h))))))
   (do promise.monad
-    [?actual (\ repository download (///repository/remote.uri artifact extension))]
+    [?actual (\ repository download (///repository/remote.uri version_template artifact extension))]
     (case ?actual
       (#try.Success actual)
-      (wrap (do try.monad
-              [output (\ encoding.utf8 decode actual)
-               actual (\ codec decode output)
+      (wrap (do {! try.monad}
+              [output (\ ! map (|>> (:coerce java/lang/String)
+                                    java/lang/String::trim
+                                    (:coerce Text))
+                         (\ encoding.utf8 decode actual))
+               actual (|> output
+                          (text.split_all_with " ")
+                          list.head
+                          (maybe.default output)
+                          (\ codec decode))
                _ (exception.assert exception [artifact extension output]
                                    (\ ///hash.equivalence = (hash library) actual))]
               (wrap (#.Some actual))))
@@ -75,15 +94,15 @@
       (#try.Failure error)
       (wrap (#try.Success #.None)))))
 
-(def: (hashed repository artifact extension)
-  (-> (Repository Promise) Artifact Extension (Promise (Try [Binary Status])))
+(def: (hashed repository version_template artifact extension)
+  (-> (Repository Promise) Version Artifact Extension (Promise (Try [Binary Status])))
   (do (try.with promise.monad)
-    [data (\ repository download (///repository/remote.uri artifact extension))
+    [data (\ repository download (///repository/remote.uri version_template artifact extension))
      ?sha-1 (..verified_hash data
-                             repository artifact (format extension ///artifact/extension.sha-1)
+                             repository version_template artifact (format extension ///artifact/extension.sha-1)
                              ///hash.sha-1 ///hash.sha-1_codec ..sha-1_does_not_match)
      ?md5 (..verified_hash data
-                           repository artifact (format extension ///artifact/extension.md5)
+                           repository version_template artifact (format extension ///artifact/extension.md5)
                            ///hash.md5 ///hash.md5_codec ..md5_does_not_match)]
     (wrap [data (case [?sha-1 ?md5]
                   [(#.Some sha-1) (#.Some md5)]
@@ -103,16 +122,21 @@
   (let [[artifact type] dependency
         extension (///artifact/extension.extension type)]
     (do (try.with promise.monad)
-      [[pom pom_status] (..hashed repository artifact ///artifact/extension.pom)
-       library_&_status (..hashed repository artifact extension)]
+      [snapshot (///metadata/snapshot.read repository artifact)
+       #let [version_template (get@ [#///metadata/snapshot.artifact #///artifact.version] snapshot)
+             artifact_version (value.format {#value.version version_template
+                                             #value.snapshot (get@ [#///metadata/snapshot.versioning #///artifact/versioning.snapshot] snapshot)})
+             artifact (set@ #///artifact.version artifact_version artifact)]
+       [pom_data pom_status] (..hashed repository version_template artifact ///artifact/extension.pom)
+       library_&_status (..hashed repository version_template artifact extension)]
       (\ promise.monad wrap
          (do try.monad
-           [pom (\ encoding.utf8 decode pom)
+           [pom (\ encoding.utf8 decode pom_data)
             pom (\ xml.codec decode pom)
-            profile (<xml>.run ///pom.parser pom)]
+            profile (<xml>.run ///pom.parser (list pom))]
            (wrap {#///package.origin (#///repository/origin.Remote "")
                   #///package.library library_&_status
-                  #///package.pom [pom pom_status]}))))))
+                  #///package.pom [pom pom_data pom_status]}))))))
 
 (type: #export Resolution
   (Dictionary Dependency Package))
@@ -149,21 +173,54 @@
         (any alternatives dependency)))))
 
 (def: #export (all repositories dependencies resolution)
-  (-> (List (Repository Promise)) (List Dependency) Resolution (Promise (Try Resolution)))
-  (case dependencies
-    #.Nil
-    (\ (try.with promise.monad) wrap resolution)
-
-    (#.Cons head tail)
-    (do (try.with promise.monad)
-      [package (case (dictionary.get head resolution)
-                 (#.Some package)
-                 (wrap package)
-
-                 #.None
-                 (..any repositories head))
-       sub_dependencies (\ promise.monad wrap (///package.dependencies package))
-       resolution (|> resolution
-                      (dictionary.put head package)
-                      (all repositories (set.to_list sub_dependencies)))]
-      (all repositories tail resolution))))
+  (-> (List (Repository Promise)) (List Dependency) Resolution
+      (Promise [(List Dependency)
+                (List Dependency)
+                Resolution]))
+  (loop [repositories repositories
+         successes (: (List Dependency) (list))
+         failures (: (List Dependency) (list))
+         dependencies dependencies
+         resolution resolution]
+    (case dependencies
+      #.Nil
+      (\ promise.monad wrap
+         [successes failures resolution])
+
+      (#.Cons head tail)
+      (case (get@ [#//.artifact #///artifact.version] head)
+        ## Skip if there is no version
+        "" (recur repositories
+                  successes
+                  failures
+                  tail
+                  resolution)
+        _ (do promise.monad
+            [?package (case (dictionary.get head resolution)
+                        (#.Some package)
+                        (wrap (#try.Success package))
+
+                        #.None
+                        (..any repositories head))]
+            (case ?package
+              (#try.Success package)
+              (let [sub_dependencies (|> package
+                                         ///package.dependencies
+                                         (try\map set.to_list)
+                                         (try.default (list)))
+                    sub_repositories (|> package
+                                         ///package.repositories
+                                         (try\map set.to_list)
+                                         (try.default (list))
+                                         (list\map (|>> (///repository/remote.repository #.None)
+                                                        ///repository.async))
+                                         (list\compose repositories))]
+                (|> resolution
+                    (dictionary.put head package)
+                    (recur sub_repositories
+                           (#.Cons head successes)
+                           failures
+                           sub_dependencies)))
+
+              (#try.Failure error)
+              (wrap [successes (#.Cons head failures) resolution])))))))
diff --git a/stdlib/source/program/aedifex/local.lux b/stdlib/source/program/aedifex/local.lux
index 279973c1a..bf8c0f780 100644
--- a/stdlib/source/program/aedifex/local.lux
+++ b/stdlib/source/program/aedifex/local.lux
@@ -7,7 +7,7 @@
     [net
      ["." uri (#+ URI)]]]]
   ["." // #_
-   ["#." artifact (#+ Artifact)]])
+   ["#." artifact (#+ Version Artifact)]])
 
 (def: / uri.separator)
 
@@ -15,7 +15,6 @@
   URI
   (format ".m2" / "repository"))
 
-(def: #export uri
-  (-> Artifact URI)
-  (|>> //artifact.uri
-       (format ..repository /)))
+(def: #export (uri version artifact)
+  (-> Version Artifact URI)
+  (format ..repository / (//artifact.uri version artifact)))
diff --git a/stdlib/source/program/aedifex/metadata.lux b/stdlib/source/program/aedifex/metadata.lux
index 0eca976c0..08dab9ed3 100644
--- a/stdlib/source/program/aedifex/metadata.lux
+++ b/stdlib/source/program/aedifex/metadata.lux
@@ -3,6 +3,10 @@
    [world
     [file (#+ Path)]]])
 
-(def: #export file
+(def: #export remote_file
   Path
   "maven-metadata.xml")
+
+(def: #export local_file
+  Path
+  "maven-metadata-local.xml")
diff --git a/stdlib/source/program/aedifex/metadata/artifact.lux b/stdlib/source/program/aedifex/metadata/artifact.lux
index c1d98a8b5..811713427 100644
--- a/stdlib/source/program/aedifex/metadata/artifact.lux
+++ b/stdlib/source/program/aedifex/metadata/artifact.lux
@@ -173,7 +173,7 @@
   (let [/ uri.separator
         group (///artifact.directory / (get@ #///artifact.group artifact))
         name (get@ #///artifact.name artifact)]
-    (%.format group / name / //.file)))
+    (%.format group / name / //.remote_file)))
 
 (def: epoch
   Instant
@@ -189,7 +189,7 @@
                 (do> try.monad
                      [(\ encoding.utf8 decode)]
                      [(\ xml.codec decode)]
-                     [(<xml>.run ..parser)])))
+                     [list (<xml>.run ..parser)])))
       
       (#try.Failure error)
       (wrap (#try.Success
diff --git a/stdlib/source/program/aedifex/metadata/snapshot.lux b/stdlib/source/program/aedifex/metadata/snapshot.lux
index 99ad25470..fa1bcb750 100644
--- a/stdlib/source/program/aedifex/metadata/snapshot.lux
+++ b/stdlib/source/program/aedifex/metadata/snapshot.lux
@@ -4,7 +4,7 @@
     [monad (#+ do)]
     [equivalence (#+ Equivalence)]]
    [control
-    [pipe (#+ do>)]
+    [pipe (#+ do> case>)]
     ["." try (#+ Try)]
     ["." exception (#+ exception:)]
     ["<>" parser
@@ -33,96 +33,25 @@
     [net
      ["." uri (#+ URI)]]]]
   ["." //
-   ["." artifact]
    ["/#" // #_
     [repository (#+ Repository)]
     ["#." artifact (#+ Group Name Version Artifact)
-     ["#/." type (#+ Type)]]]])
-
-(def: snapshot
-  "SNAPSHOT")
-
-(type: #export Time_Stamp
-  Instant)
-
-(type: #export Build
-  Nat)
-
-(type: #export Versioning
-  {#time_stamp Time_Stamp
-   #build Build
-   #snapshot (List Type)})
-
-(type: #export Value
-  [Version Time_Stamp Build])
+     ["#/." type (#+ Type)]
+     ["#/." versioning (#+ Versioning)]
+     ["#/." snapshot
+      ["#/." version]]]]])
 
 (type: #export Metadata
   {#artifact Artifact
    #versioning Versioning})
 
-(def: (pad value)
-  (-> Nat Text)
-  (if (n.< 10 value)
-    (%.format "0" (%.nat value))
-    (%.nat value)))
-
-(def: (date_format value)
-  (%.Format Date)
-  (%.format (|> value date.year year.value .nat %.nat)
-            (|> value date.month month.number ..pad)
-            (|> value date.day_of_month ..pad)))
-
-(def: (time_format value)
-  (%.Format Time)
-  (let [(^slots [#time.hour #time.minute #time.second]) (time.clock value)]
-    (%.format (..pad hour)
-              (..pad minute)
-              (..pad second))))
-
-(def: (instant_format value)
-  (%.Format Instant)
-  (%.format (..date_format (instant.date value))
-            (..time_format (instant.time value))))
-
-(template [<separator> <name>]
-  [(def: <name>
-     <separator>)]
-
-  ["." time_stamp_separator]
-  ["-" value_separator]
-  )
-
-(def: (time_stamp_format value)
-  (%.Format Time_Stamp)
-  (%.format (..date_format (instant.date value))
-            ..time_stamp_separator
-            (..time_format (instant.time value))))
-
-(def: (value_format [version time_stamp build])
-  (%.Format Value)
-  (%.format (text.replace_all ..snapshot
-                              (..time_stamp_format time_stamp)
-                              version)
-            ..value_separator
-            (%.nat build)))
-
 (template [<definition> <tag>]
   [(def: <definition> xml.Tag ["" <tag>])]
 
   [<group> "groupId"]
   [<name> "artifactId"]
   [<version> "version"]
-  [<last_updated> "lastUpdated"]
   [<metadata> "metadata"]
-  [<versioning> "versioning"]
-  [<snapshot> "snapshot"]
-  [<timestamp> "timestamp"]
-  [<build_number> "buildNumber"]
-  [<snapshot_versions> "snapshotVersions"]
-  [<snapshot_version> "snapshotVersion"]
-  [<extension> "extension"]
-  [<value> "value"]
-  [<updated> "updated"]
   )
 
 (template [<name> <type> <tag> <pre>]
@@ -133,33 +62,8 @@
   [format_group Group ..<group> (|>)]
   [format_name Name ..<name> (|>)]
   [format_version Version ..<version> (|>)]
-  [format_last_updated Instant ..<last_updated> ..instant_format]
-  [format_time_stamp Instant ..<timestamp> ..time_stamp_format]
-  [format_build_number Nat ..<build_number> %.nat]
-  [format_extension Type ..<extension> (|>)]
-  [format_value Value ..<value> ..value_format]
-  [format_updated Instant ..<updated> ..instant_format]
   )
 
-(def: (format_snapshot value type)
-  (-> Value Type XML)
-  (<| (#xml.Node ..<snapshot_version> xml.attributes)
-      (list (..format_extension type)
-            (..format_value value)
-            (let [[version time_stamp build] value]
-              (..format_updated time_stamp)))))
-
-(def: (format_versioning version (^slots [#time_stamp #build #snapshot]))
-  (-> Version Versioning XML)
-  (<| (#xml.Node ..<versioning> xml.attributes)
-      (list (<| (#xml.Node ..<snapshot> xml.attributes)
-                (list (..format_time_stamp time_stamp)
-                      (..format_build_number build)))
-            (..format_last_updated time_stamp)
-            (<| (#xml.Node ..<snapshot_versions> xml.attributes)
-                (list\map (..format_snapshot [version time_stamp build])
-                          snapshot)))))
-
 (def: #export (format (^slots [#artifact #versioning]))
   (-> Metadata XML)
   (let [(^slots [#///artifact.group #///artifact.name #///artifact.version]) artifact]
@@ -168,7 +72,7 @@
                (list (..format_group group)
                      (..format_name name)
                      (..format_version version)
-                     (..format_versioning version versioning)))))
+                     (///artifact/versioning.format versioning)))))
 
 (def: (sub tag parser)
   (All [a] (-> xml.Tag (Parser a) (Parser a)))
@@ -180,135 +84,46 @@
   (-> xml.Tag (Parser Text))
   (..sub tag <xml>.text))
 
-(def: date_parser
-  (<text>.Parser Date)
-  (do <>.monad
-    [year (<>.codec n.decimal (<text>.exactly 4 <text>.decimal))
-     year (<>.lift (year.year (.int year)))
-     month (<>.codec n.decimal (<text>.exactly 2 <text>.decimal))
-     month (<>.lift (month.by_number month))
-     day_of_month (<>.codec n.decimal (<text>.exactly 2 <text>.decimal))]
-    (<>.lift (date.date year month day_of_month))))
-
-(def: time_parser
-  (<text>.Parser Time)
-  (do <>.monad
-    [hour (<>.codec n.decimal (<text>.exactly 2 <text>.decimal))
-     minute (<>.codec n.decimal (<text>.exactly 2 <text>.decimal))
-     second (<>.codec n.decimal (<text>.exactly 2 <text>.decimal))]
-    (<>.lift (time.time
-              {#time.hour hour
-               #time.minute minute
-               #time.second second
-               #time.milli_second 0}))))
-
-(def: last_updated_parser
-  (Parser Instant)
-  (<text>.embed (do <>.monad
-                  [date ..date_parser
-                   time ..time_parser]
-                  (wrap (instant.from_date_time date time)))
-                (..text ..<last_updated>)))
-
-(def: time_stamp_parser
-  (Parser Time_Stamp)
-  (<text>.embed (do <>.monad
-                  [date ..date_parser
-                   _ (<text>.this ..time_stamp_separator)
-                   time ..time_parser]
-                  (wrap (instant.from_date_time date time)))
-                (..text ..<timestamp>)))
-
-(def: build_parser
-  (Parser Build)
-  (<text>.embed (<>.codec n.decimal
-                          (<text>.many <text>.decimal))
-                (..text ..<build_number>)))
-
-(exception: #export (time_stamp_mismatch {expected Time_Stamp} {actual Text})
-  (exception.report
-   ["Expected time-stamp" (instant_format expected)]
-   ["Actual time-stamp" actual]))
-
-(exception: #export (value_mismatch {expected Value} {actual Text})
-  (exception.report
-   ["Expected" (..value_format expected)]
-   ["Actual" actual]))
-
-(def: (snapshot_parser expected)
-  (-> Value (Parser Type))
-  (<| (..sub ..<snapshot_version>)
-      (do <>.monad
-        [#let [[version time_stamp build] expected]
-         updated (<xml>.somewhere (..text ..<updated>))
-         _ (<>.assert (exception.construct ..time_stamp_mismatch [time_stamp updated])
-                      (\ text.equivalence = (instant_format time_stamp) updated))
-         actual (<xml>.somewhere (..text ..<value>))
-         _ (<>.assert (exception.construct ..value_mismatch [expected actual])
-                      (\ text.equivalence = (..value_format expected) actual))]
-        (<xml>.somewhere (..text ..<extension>)))))
-
-(def: (versioning_parser version)
-  (-> Version (Parser Versioning))
-  (<| (..sub ..<versioning>)
-      (do <>.monad
-        [[time_stamp build] (<| <xml>.somewhere
-                                (..sub ..<snapshot>)
-                                (<>.and (<xml>.somewhere ..time_stamp_parser)
-                                        (<xml>.somewhere ..build_parser)))
-         last_updated (<xml>.somewhere ..last_updated_parser)
-         _ (<>.assert (exception.construct ..time_stamp_mismatch [time_stamp (instant_format last_updated)])
-                      (\ instant.equivalence = time_stamp last_updated))
-         snapshot (<| <xml>.somewhere
-                      (..sub ..<snapshot_versions>)
-                      (<>.some (..snapshot_parser [version time_stamp build])))]
-        (wrap {#time_stamp time_stamp
-               #build build
-               #snapshot snapshot}))))
-
 (def: #export parser
   (Parser Metadata)
   (<| (..sub ..<metadata>)
-      (do <>.monad
+      (do {! <>.monad}
         [group (<xml>.somewhere (..text ..<group>))
          name (<xml>.somewhere (..text ..<name>))
          version (<xml>.somewhere (..text ..<version>))
-         versioning (<xml>.somewhere (..versioning_parser version))]
+         versioning (\ ! map
+                       (update@ #///artifact/versioning.versions
+                                (: (-> (List ///artifact/snapshot/version.Version)
+                                       (List ///artifact/snapshot/version.Version))
+                                   (|>> (case> (^ (list))
+                                               (list {#///artifact/snapshot/version.extension ///artifact/type.jvm_library
+                                                      #///artifact/snapshot/version.value version
+                                                      #///artifact/snapshot/version.updated instant.epoch})
+
+                                               versions
+                                               versions))))
+                       (<xml>.somewhere ///artifact/versioning.parser))]
         (wrap {#artifact {#///artifact.group group
                           #///artifact.name name
                           #///artifact.version version}
                #versioning versioning}))))
 
-(def: versioning_equivalence
-  (Equivalence Versioning)
-  ($_ product.equivalence
-      instant.equivalence
-      n.equivalence
-      (list.equivalence text.equivalence)
-      ))
-
 (def: #export equivalence
   (Equivalence Metadata)
   ($_ product.equivalence
       ///artifact.equivalence
-      ..versioning_equivalence
+      ///artifact/versioning.equivalence
       ))
 
 (def: #export (uri artifact)
   (-> Artifact URI)
   (let [/ uri.separator
-        version (get@ #///artifact.version artifact)
-        artifact (///artifact.uri artifact)]
-    (%.format artifact / version / //.file)))
-
-(def: epoch
-  Instant
-  (instant.from_millis +0))
-
-(def: init_versioning
-  {#time_stamp ..epoch
-   #build 0
-   #snapshot (list)})
+        group (|> artifact
+                  (get@ #///artifact.group)
+                  (///artifact.directory /))
+        name (get@ #///artifact.name artifact)
+        version (get@ #///artifact.version artifact)]
+    (%.format group / name / version / //.remote_file)))
 
 (def: #export (read repository artifact)
   (-> (Repository Promise) Artifact (Promise (Try Metadata)))
@@ -320,12 +135,12 @@
                 (do> try.monad
                      [(\ encoding.utf8 decode)]
                      [(\ xml.codec decode)]
-                     [(<xml>.run ..parser)])))
+                     [list (<xml>.run ..parser)])))
       
       (#try.Failure error)
       (wrap (#try.Success
              {#artifact artifact
-              #versioning ..init_versioning})))))
+              #versioning ///artifact/versioning.init})))))
 
 (def: #export (write repository artifact metadata)
   (-> (Repository Promise) Artifact Metadata (Promise (Try Any)))
diff --git a/stdlib/source/program/aedifex/package.lux b/stdlib/source/program/aedifex/package.lux
index f6ba87078..445c92987 100644
--- a/stdlib/source/program/aedifex/package.lux
+++ b/stdlib/source/program/aedifex/package.lux
@@ -10,6 +10,8 @@
     ["." sum]
     ["." product]
     ["." binary (#+ Binary)]
+    [text
+     ["." encoding]]
     [format
      ["." xml (#+ XML)]]
     [collection
@@ -21,12 +23,13 @@
    [dependency (#+ Dependency)
     ["#." status (#+ Status)]]
    [repository
+    [remote (#+ Address)]
     ["#." origin (#+ Origin)]]])
 
 (type: #export Package
   {#origin Origin
    #library [Binary Status]
-   #pom [XML Status]})
+   #pom [XML Binary Status]})
 
 (template [<name> <tag>]
   [(def: #export (<name> package)
@@ -46,19 +49,35 @@
   (-> XML Binary Package)
   {#origin (#//origin.Local "")
    #library [library #//status.Unverified]
-   #pom [pom #//status.Unverified]})
+   #pom [pom
+         (|> pom (\ xml.codec encode) (\ encoding.utf8 encode))
+         #//status.Unverified]})
 
 (def: #export dependencies
   (-> Package (Try (Set Dependency)))
   (|>> (get@ #pom)
        product.left
+       list
        (<xml>.run //pom.parser)
        (try\map (get@ #/.dependencies))))
 
+(def: #export repositories
+  (-> Package (Try (Set Address)))
+  (|>> (get@ #pom)
+       product.left
+       list
+       (<xml>.run //pom.parser)
+       (try\map (get@ #/.repositories))))
+
 (def: #export equivalence
   (Equivalence Package)
   ($_ product.equivalence
       //origin.equivalence
-      (product.equivalence binary.equivalence //status.equivalence)
-      (product.equivalence xml.equivalence //status.equivalence)
+      ($_ product.equivalence
+          binary.equivalence
+          //status.equivalence)
+      ($_ product.equivalence
+          xml.equivalence
+          binary.equivalence
+          //status.equivalence)
       ))
diff --git a/stdlib/source/program/aedifex/parser.lux b/stdlib/source/program/aedifex/parser.lux
index 4a21b341a..411b4665b 100644
--- a/stdlib/source/program/aedifex/parser.lux
+++ b/stdlib/source/program/aedifex/parser.lux
@@ -171,6 +171,9 @@
                (<>.and <c>.text
                        ..repository))))
 
+(def: default_repository
+  "https://repo1.maven.org/maven2/")
+
 (def: profile
   (Parser /.Profile)
   (do {! <>.monad}
@@ -190,7 +193,8 @@
            ^repositories (: (Parser (Set //repository.Address))
                             (|> (..plural input "repositories" ..repository)
                                 (\ ! map (set.from_list text.hash))
-                                (<>.default (set.new text.hash))))
+                                (<>.default (set.new text.hash))
+                                (\ ! map (set.add ..default_repository))))
            ^dependencies (: (Parser (Set //dependency.Dependency))
                             (|> (..plural input "dependencies" ..dependency)
                                 (\ ! map (set.from_list //dependency.hash))
diff --git a/stdlib/source/program/aedifex/pom.lux b/stdlib/source/program/aedifex/pom.lux
index f085e2808..f105f07b6 100644
--- a/stdlib/source/program/aedifex/pom.lux
+++ b/stdlib/source/program/aedifex/pom.lux
@@ -11,6 +11,7 @@
    [data
     ["." name]
     ["." maybe ("#\." functor)]
+    ["." text]
     [format
      ["_" xml (#+ Tag XML)]]
     [collection
@@ -150,8 +151,8 @@
   (<>.and <xml>.tag
           (<xml>.children <xml>.text)))
 
-(def: parse_dependency
-  (Parser Dependency)
+(def: (parse_dependency own_version parent_version)
+  (-> Text Text (Parser Dependency))
   (do {! <>.monad}
     [properties (\ ! map (dictionary.from_list name.hash)
                    (<xml>.children (<>.some ..parse_property)))]
@@ -159,28 +160,47 @@
         try.from_maybe
         (do maybe.monad
           [group (dictionary.get ["" ..group_tag] properties)
-           artifact (dictionary.get ["" ..artifact_tag] properties)
-           version (dictionary.get ["" ..version_tag] properties)]
+           artifact (dictionary.get ["" ..artifact_tag] properties)]
           (wrap {#//dependency.artifact {#//artifact.group group
                                          #//artifact.name artifact
-                                         #//artifact.version version}
+                                         #//artifact.version (|> properties
+                                                                 (dictionary.get ["" ..version_tag])
+                                                                 (maybe.default "")
+                                                                 (text.replace_all "${project.version}" own_version)
+                                                                 (text.replace_all "${project.parent.version}" parent_version))}
                  #//dependency.type (|> properties
                                         (dictionary.get ["" "type"])
-                                        (maybe.default //artifact/type.lux_library))})))))
+                                        (maybe.default //artifact/type.jvm_library))})))))
 
-(def: parse_dependencies
-  (Parser (List Dependency))
+(def: (parse_dependencies own_version parent_version)
+  (-> Text Text (Parser (List Dependency)))
   (do {! <>.monad}
     [_ (<xml>.node ["" ..dependencies_tag])]
-    (<xml>.children (<>.some ..parse_dependency))))
+    (<xml>.children (<>.some (..parse_dependency own_version parent_version)))))
+
+(def: own_version
+  (Parser Text)
+  (do <>.monad
+    [_ (<xml>.node ["" ..version_tag])]
+    (<xml>.children <xml>.text)))
+
+(def: parent_version
+  (Parser Text)
+  (do <>.monad
+    [_ (<xml>.node ["" "parent"])]
+    ..own_version))
 
 (def: #export parser
   (Parser /.Profile)
   (do {! <>.monad}
-    [_ (<xml>.node ["" ..project_tag])]
+    [own_version (<>.default "" (<xml>.somewhere ..own_version))
+     parent_version (<>.default "" (<xml>.somewhere ..parent_version))
+     _ (<xml>.node ["" ..project_tag])]
     (<xml>.children
      (do !
-       [dependencies (<xml>.somewhere ..parse_dependencies)
+       [dependencies (|> (..parse_dependencies own_version parent_version)
+                         <xml>.somewhere
+                         (<>.default (list)))
         _ (<>.some <xml>.ignore)]
        (wrap (|> (\ /.monoid identity)
                  (update@ #/.dependencies (function (_ empty)
diff --git a/stdlib/source/program/aedifex/repository/local.lux b/stdlib/source/program/aedifex/repository/local.lux
index f313b3176..7ac384efa 100644
--- a/stdlib/source/program/aedifex/repository/local.lux
+++ b/stdlib/source/program/aedifex/repository/local.lux
@@ -19,7 +19,8 @@
      ["." uri (#+ URI)]]]]
   ["." //
    ["/#" // #_
-    ["#." local]]])
+    ["#." local]
+    ["#." metadata]]])
 
 (def: (root /)
   (-> Text Path)
@@ -29,18 +30,23 @@
   (-> Text URI Path)
   (text.replace_all uri.separator))
 
-(def: (file program system uri)
+(def: (file program system create? uri)
   (-> (Program Promise)
       (file.System Promise)
+      Bit
       URI
       (Promise (Try (File Promise))))
   (do {! promise.monad}
-    [home (\ program home [])
+    [#let [uri (text.replace_once ///metadata.remote_file ///metadata.local_file uri)]
+     home (\ program home [])
      #let [/ (\ system separator)
            absolute_path (format home / (..root /) / (..path / uri))]]
-    (do {! (try.with !)}
-      [_ (: (Promise (Try Path))
-            (file.make_directories promise.monad system (file.parent system absolute_path)))]
+    (if create?
+      (do {! (try.with !)}
+        [_ (: (Promise (Try Path))
+              (file.make_directories promise.monad system (file.parent system absolute_path)))]
+        (: (Promise (Try (File Promise)))
+           (file.get_file promise.monad system absolute_path)))
       (: (Promise (Try (File Promise)))
          (!.use (\ system file) absolute_path)))))
 
@@ -49,10 +55,10 @@
 
   (def: (download uri)
     (do {! (try.with promise.monad)}
-      [file (..file program system uri)]
+      [file (..file program system false uri)]
       (!.use (\ file content) [])))
 
   (def: (upload uri content)
     (do {! (try.with promise.monad)}
-      [file (..file program system uri)]
+      [file (..file program system true uri)]
       (!.use (\ file over_write) [content]))))
diff --git a/stdlib/source/program/aedifex/repository/remote.lux b/stdlib/source/program/aedifex/repository/remote.lux
index 4979e5429..4b61bc36c 100644
--- a/stdlib/source/program/aedifex/repository/remote.lux
+++ b/stdlib/source/program/aedifex/repository/remote.lux
@@ -26,7 +26,7 @@
   ["." //
    ["#." identity (#+ Identity)]
    ["/#" // #_
-    ["#." artifact (#+ Artifact)
+    ["#." artifact (#+ Version Artifact)
      [extension (#+ Extension)]]]])
 
 (type: #export Address
@@ -75,9 +75,9 @@
   (exception.report
    ["Code" (%.int code)]))
 
-(def: #export (uri artifact extension)
-  (-> Artifact Extension URI)
-  (format (///artifact.uri artifact) extension))
+(def: #export (uri version_template artifact extension)
+  (-> Version Artifact Extension URI)
+  (format (///artifact.uri version_template artifact) extension))
 
 (def: buffer_size
   (n.* 512 1,024))
@@ -99,19 +99,21 @@
        input (|> connection
                  java/net/URLConnection::getInputStream
                  (\ ! map (|>> java/io/BufferedInputStream::new)))
-       #let [buffer (binary.create ..buffer_size)]]
-      (loop [output (\ binary.monoid identity)]
-        (do !
-          [bytes_read (java/io/BufferedInputStream::read buffer +0 (.int ..buffer_size) input)]
-          (case bytes_read
-            -1 (do !
-                 [_ (java/lang/AutoCloseable::close input)]
-                 (wrap output))
-            _ (if (n.= ..buffer_size bytes_read)
-                (recur (\ binary.monoid compose output buffer))
+       #let [buffer (binary.create ..buffer_size)]
+       output (loop [output (\ binary.monoid identity)]
                 (do !
-                  [chunk (\ io.monad wrap (binary.slice 0 (.nat bytes_read) buffer))]
-                  (recur (\ binary.monoid compose output chunk)))))))))
+                  [bytes_read (java/io/BufferedInputStream::read buffer +0 (.int ..buffer_size) input)]
+                  (case bytes_read
+                    -1 (do !
+                         [_ (java/lang/AutoCloseable::close input)]
+                         (wrap output))
+                    +0 (recur output)
+                    _ (if (n.= ..buffer_size bytes_read)
+                        (recur (\ binary.monoid compose output buffer))
+                        (do !
+                          [chunk (\ io.monad wrap (binary.slice 0 (dec (.nat bytes_read)) buffer))]
+                          (recur (\ binary.monoid compose output chunk)))))))]
+      (wrap output)))
 
   (def: (upload uri content)
     (case identity
diff --git a/stdlib/source/test/aedifex/artifact.lux b/stdlib/source/test/aedifex/artifact.lux
index 7d91ebed7..9d2cf9069 100644
--- a/stdlib/source/test/aedifex/artifact.lux
+++ b/stdlib/source/test/aedifex/artifact.lux
@@ -21,11 +21,9 @@
   ["." / #_
    ["#." type]
    ["#." extension]
-   ["#." value]
+   ["#." time]
    ["#." versioning]
-   ["#." time_stamp
-    ["#/." date]
-    ["#/." time]]]
+   ["#." snapshot]]
   {#program
    ["." /]})
 
@@ -47,9 +45,7 @@
                  
                  /type.test
                  /extension.test
-                 /value.test
+                 /time.test
                  /versioning.test
-                 /time_stamp.test
-                 /time_stamp/date.test
-                 /time_stamp/time.test
+                 /snapshot.test
                  ))))
diff --git a/stdlib/source/test/lux.lux b/stdlib/source/test/lux.lux
index f1200381a..a39671ea4 100644
--- a/stdlib/source/test/lux.lux
+++ b/stdlib/source/test/lux.lux
@@ -93,38 +93,9 @@
                   (check_neighbors odd? value)
                   (check_neighbors even? value))))))
 
-(type: (Choice a)
-  (-> a a a))
-
-(type: (Order a)
-  (-> a a Bit))
-
 (type: (Equivalence a)
   (-> a a Bit))
 
-(def: (choice rand_gen = [< choose])
-  (All [a] (-> (Random a) (Equivalence a) [(Order a) (Choice a)] Test))
-  (do random.monad
-    [left rand_gen
-     right rand_gen
-     #let [choice (choose left right)]]
-    ($_ _.and
-        (_.test "The choice between 2 values is one of them."
-                (or (= left choice)
-                    (= right choice)))
-        (_.test "The choice between 2 values implies an order relationship between them."
-                (if (= left choice)
-                  (< right choice)
-                  (< left choice))))))
-
-(def: (minimum_and_maximum rand_gen = min' max')
-  (All [a] (-> (Random a) (Equivalence a) [(Order a) (Choice a)] [(Order a) (Choice a)] Test))
-  ($_ _.and
-      (<| (_.context "Minimum.")
-          (choice rand_gen = min'))
-      (<| (_.context "Maximum.")
-          (choice rand_gen = max'))))
-
 (def: (conversion rand_gen forward backward =)
   (All [a b] (-> (Random a) (-> a b) (-> b a) (Equivalence a) Test))
   (do random.monad
@@ -213,6 +184,18 @@
                            @.js on_valid_host}
                           on_default))))))
 
+(def: conversion_tests
+  Test
+  (`` ($_ _.and
+          (~~ (template [<=> <forward> <backward> <gen>]
+                [(<| (_.context (format (%.name (name_of <forward>))
+                                        " " (%.name (name_of <backward>))))
+                     (..conversion <gen> <forward> <backward> <=>))]
+
+                [i.= .nat .int (random\map (i.% +1,000,000) random.int)]
+                [n.= .int .nat (random\map (n.%  1,000,000) random.nat)]
+                )))))
+
 (def: sub_tests
   Test
   (let [tail (: (List Test)
@@ -236,6 +219,7 @@
                           ))))
 
 (def: test
+  Test
   (<| (_.context (name.module (name_of /._)))
       ($_ _.and
           (<| (_.context "Identity.")
@@ -248,30 +232,8 @@
                       (..even_or_odd random.nat n.even? n.odd?))
                   (<| (_.context "Integers.")
                       (..even_or_odd random.int i.even? i.odd?))))
-          (<| (_.context "Minimum and maximum.")
-              (`` ($_ _.and
-                      (~~ (template [<=> <lt> <min> <gt> <max> <gen> <context>]
-                            [(<| (_.context <context>)
-                                 (..minimum_and_maximum <gen> <=> [<lt> <min>] [<gt> <max>]))]
-
-                            [i.= i.< i.min i.> i.max random.int       "Integers."]
-                            [n.= n.< n.min n.> n.max random.nat       "Natural numbers."]
-                            [r.= r.< r.min r.> r.max random.rev       "Revolutions."]
-                            [f.= f.< f.min f.> f.max random.safe_frac "Fractions."]
-                            )))))
           (<| (_.context "Conversion.")
-              (`` ($_ _.and
-                      (~~ (template [<=> <forward> <backward> <gen>]
-                            [(<| (_.context (format (%.name (name_of <forward>))
-                                                    " " (%.name (name_of <backward>))))
-                                 (..conversion <gen> <forward> <backward> <=>))]
-
-                            [i.= .nat   .int   (random\map (i.% +1,000,000) random.int)]
-                            [n.= .int   .nat   (random\map (n.%  1,000,000) random.nat)]
-                            [i.= i.frac f.int  (random\map (i.% +1,000,000) random.int)]
-                            [f.= f.int  i.frac (random\map (|>> (i.% +1,000,000) i.frac) random.int)]
-                            [r.= r.frac f.rev  frac_rev]
-                            )))))
+              ..conversion_tests)
           (<| (_.context "Prelude macros.")
               ..prelude_macros)
           (<| (_.context "Templates.")
diff --git a/stdlib/source/test/lux/data/name.lux b/stdlib/source/test/lux/data/name.lux
index 62c576d27..e413afc95 100644
--- a/stdlib/source/test/lux/data/name.lux
+++ b/stdlib/source/test/lux/data/name.lux
@@ -42,7 +42,7 @@
                    (_.for [/.equivalence]
                           ($equivalence.spec /.equivalence (..random sizeM1 sizeS1)))
                    (_.for [/.hash]
-                          (|> (random.ascii 2)
+                          (|> (random.ascii 1)
                               (\ ! map (|>> [""]))
                               ($hash.spec /.hash)))
                    (_.for [/.order]
diff --git a/stdlib/source/test/lux/data/text.lux b/stdlib/source/test/lux/data/text.lux
index c89ca97ba..983649a89 100644
--- a/stdlib/source/test/lux/data/text.lux
+++ b/stdlib/source/test/lux/data/text.lux
@@ -240,7 +240,7 @@
           (_.for [/.equivalence]
                  ($equivalence.spec /.equivalence (random.ascii 2)))
           (_.for [/.hash]
-                 (|> (random.ascii 2)
+                 (|> (random.ascii 1)
                      ($hash.spec /.hash)))
           (_.for [/.order]
                  ($order.spec /.order (random.ascii 2)))
diff --git a/stdlib/source/test/lux/macro/code.lux b/stdlib/source/test/lux/macro/code.lux
index 0f217e335..730671b5b 100644
--- a/stdlib/source/test/lux/macro/code.lux
+++ b/stdlib/source/test/lux/macro/code.lux
@@ -170,8 +170,12 @@
                                [/.local_identifier ..random_text #.Identifier]
                                )))))
           (do {! random.monad}
-            [[original substitute] (random.and ..random ..random)
-             [sample expected] (..replace_simulation [original substitute])]
+            [[original substitute] (random.filter (function (_ [original substitute])
+                                                    (not (\ /.equivalence = original substitute)))
+                                                  (random.and ..random ..random))
+             [sample expected] (random.filter (function (_ [sample expected])
+                                                (not (\ /.equivalence = sample expected)))
+                                              (..replace_simulation [original substitute]))]
             (_.cover [/.replace]
                      (\ /.equivalence =
                         expected
diff --git a/stdlib/source/test/lux/math/modular.lux b/stdlib/source/test/lux/math/modular.lux
index b0c69b814..461d5bfac 100644
--- a/stdlib/source/test/lux/math/modular.lux
+++ b/stdlib/source/test/lux/math/modular.lux
@@ -4,6 +4,7 @@
    ["." type ("#\." equivalence)]
    [abstract
     [monad (#+ do)]
+    ["." predicate]
     {[0 #spec]
      [/
       ["$." equivalence]
@@ -41,7 +42,8 @@
         [param\\% ($//.random +1,000,000)
          param (..random param\\%)
 
-         subject\\% (random.filter (|>> (//.= param\\%) not)
+         subject\\% (random.filter (predicate.intersect (|>> //.divisor (i.> +2))
+                                                        (|>> (//.= param\\%) not))
                                    ($//.random +1,000,000))
          subject (..random subject\\%)
          another (..random subject\\%)]
diff --git a/stdlib/source/test/lux/type/resource.lux b/stdlib/source/test/lux/type/resource.lux
index 54150772e..1a56d8d08 100644
--- a/stdlib/source/test/lux/type/resource.lux
+++ b/stdlib/source/test/lux/type/resource.lux
@@ -1,53 +1,192 @@
 (.module:
   [lux #*
-   ["%" data/text/format (#+ format)]
    ["_" test (#+ Test)]
+   ["." meta]
    [abstract
-    [monad
+    ["." monad
      [indexed (#+ do)]]]
    [control
-    ["." io]]
+    ["." io]
+    ["." try]
+    ["." exception (#+ Exception)]
+    [concurrency
+     ["." promise]]
+    [parser
+     ["<.>" code]]]
+   [data
+    ["." text ("#\." equivalence)
+     ["%" format (#+ format)]]]
+   ["." macro
+    [syntax (#+ syntax:)]
+    ["." code]]
    [math
-    [number
-     ["n" nat]]]]
+    ["." random]]]
   {1
    ["." / (#+ Res)]})
 
+(def: pure
+  Test
+  (monad.do {! random.monad}
+    [pre (\ ! map %.nat random.nat)
+     post (\ ! map %.nat random.nat)]
+    (_.for [/.Linear /.pure /.run_pure]
+           (`` ($_ _.and
+                   (~~ (template [<coverage> <bindings>]
+                         [(_.cover <coverage>
+                                   (<| (text\= (format pre post))
+                                       /.run_pure
+                                       (do /.pure
+                                         <bindings>
+                                         (wrap (format left right)))))]
+                         
+                         [[/.Affine /.Key /.Res /.Ordered /.ordered_pure
+                           /.Relevant /.read_pure]
+                          [res|left (/.ordered_pure pre)
+                           res|right (/.ordered_pure post)
+                           right (/.read_pure res|right)
+                           left (/.read_pure res|left)]]
+                         [[/.Commutative /.commutative_pure /.exchange_pure]
+                          [res|left (/.commutative_pure pre)
+                           res|right (/.commutative_pure post)
+                           _ (/.exchange_pure [1 0])
+                           left (/.read_pure res|left)
+                           right (/.read_pure res|right)]]
+                         [[/.group_pure /.un_group_pure]
+                          [res|left (/.commutative_pure pre)
+                           res|right (/.commutative_pure post)
+                           _ (/.group_pure 2)
+                           _ (/.un_group_pure 2)
+                           right (/.read_pure res|right)
+                           left (/.read_pure res|left)]]
+                         [[/.lift_pure]
+                          [left (/.lift_pure pre)
+                           right (/.lift_pure post)]]
+                         ))
+                   )))))
+
+(def: sync
+  Test
+  (monad.do {! random.monad}
+    [pre (\ ! map %.nat random.nat)
+     post (\ ! map %.nat random.nat)]
+    (_.for [/.Linear /.sync /.run_sync]
+           (`` ($_ _.and
+                   (~~ (template [<coverage> <bindings>]
+                         [(_.cover <coverage>
+                                   (<| (text\= (format pre post))
+                                       io.run
+                                       /.run_sync
+                                       (do /.sync
+                                         <bindings>
+                                         (wrap (format left right)))))]
+
+                         [[/.Affine /.Key /.Res /.Ordered /.ordered_sync
+                           /.Relevant /.read_sync]
+                          [res|left (/.ordered_sync pre)
+                           res|right (/.ordered_sync post)
+                           right (/.read_sync res|right)
+                           left (/.read_sync res|left)]]
+                         [[/.Commutative /.commutative_sync /.exchange_sync]
+                          [res|left (/.commutative_sync pre)
+                           res|right (/.commutative_sync post)
+                           _ (/.exchange_sync [1 0])
+                           left (/.read_sync res|left)
+                           right (/.read_sync res|right)]]
+                         [[/.group_sync /.un_group_sync]
+                          [res|left (/.commutative_sync pre)
+                           res|right (/.commutative_sync post)
+                           _ (/.group_sync 2)
+                           _ (/.un_group_sync 2)
+                           right (/.read_sync res|right)
+                           left (/.read_sync res|left)]]
+                         [[/.lift_sync]
+                          [left (/.lift_sync (io.io pre))
+                           right (/.lift_sync (io.io post))]]
+                         ))
+                   )))))
+
+(def: async
+  Test
+  (monad.do {! random.monad}
+    [pre (\ ! map %.nat random.nat)
+     post (\ ! map %.nat random.nat)]
+    (_.for [/.Linear /.async /.run_async]
+           (`` ($_ _.and
+                   (~~ (template [<coverage> <bindings>]
+                         [(wrap (monad.do promise.monad
+                                  [outcome (/.run_async
+                                            (do /.async
+                                              <bindings>
+                                              (wrap (format left right))))]
+                                  (_.cover' <coverage>
+                                            (text\= (format pre post)
+                                                    outcome))))]
+
+                         [[/.Affine /.Key /.Res /.Ordered /.ordered_async
+                           /.Relevant /.read_async]
+                          [res|left (/.ordered_async pre)
+                           res|right (/.ordered_async post)
+                           right (/.read_async res|right)
+                           left (/.read_async res|left)]]
+                         [[/.Commutative /.commutative_async /.exchange_async]
+                          [res|left (/.commutative_async pre)
+                           res|right (/.commutative_async post)
+                           _ (/.exchange_async [1 0])
+                           left (/.read_async res|left)
+                           right (/.read_async res|right)]]
+                         [[/.group_async /.un_group_async]
+                          [res|left (/.commutative_async pre)
+                           res|right (/.commutative_async post)
+                           _ (/.group_async 2)
+                           _ (/.un_group_async 2)
+                           right (/.read_async res|right)
+                           left (/.read_async res|left)]]
+                         [[/.lift_async]
+                          [left (/.lift_async (promise.resolved pre))
+                           right (/.lift_async (promise.resolved post))]]
+                         ))
+                   )))))
+
+(syntax: (with_error {exception <code>.identifier} to_expand)
+  (monad.do meta.monad
+    [[_ _ _ exception] (meta.find_export exception)]
+    (function (_ compiler)
+      (#.Right [compiler
+                (list (code.bit (case ((macro.expand_once to_expand) compiler)
+                                  (#try.Success _)
+                                  false
+                                  
+                                  (#try.Failure error)
+                                  true)))]))))
+
 (def: #export test
   Test
-  (<| (_.context (%.name (name_of /._)))
+  (<| (_.covering /._)
+      (_.for [/.Procedure])
       ($_ _.and
-          (_.test "Can produce and consume keys in an ordered manner."
-                  (<| (n.= (n.+ 123 456))
-                      io.run
-                      /.run_sync
-                      (do /.sync
-                        [res|left (/.ordered_sync 123)
-                         res|right (/.ordered_sync 456)
-                         right (/.read_sync res|right)
-                         left (/.read_sync res|left)]
-                        (wrap (n.+ left right)))))
-          (_.test "Can exchange commutative keys."
-                  (<| (n.= (n.+ 123 456))
-                      io.run
-                      /.run_sync
-                      (do /.sync
-                        [res|left (/.commutative_sync 123)
-                         res|right (/.commutative_sync 456)
-                         _ (/.exchange_sync [1 0])
-                         left (/.read_sync res|left)
-                         right (/.read_sync res|right)]
-                        (wrap (n.+ left right)))))
-          (_.test "Can group and un-group keys."
-                  (<| (n.= (n.+ 123 456))
-                      io.run
-                      /.run_sync
-                      (do /.sync
-                        [res|left (/.commutative_sync 123)
-                         res|right (/.commutative_sync 456)
-                         _ (/.group_sync 2)
-                         _ (/.un_group_sync 2)
-                         right (/.read_sync res|right)
-                         left (/.read_sync res|left)]
-                        (wrap (n.+ left right)))))
+          ..pure
+          ..sync
+          ..async
+
+          (_.cover [/.amount_cannot_be_zero]
+                   (`` (and (~~ (template [<group|un_group>]
+                                  [(with_error /.amount_cannot_be_zero
+                                     (<group|un_group> 0))]
+
+                                  [/.group_pure]
+                                  [/.group_sync]
+                                  [/.group_async]
+                                  [/.un_group_pure]
+                                  [/.un_group_sync]
+                                  [/.un_group_async]
+                                  )))))
+          (_.cover [/.index_cannot_be_repeated]
+                   (`` (and (~~ (template [<exchange>]
+                                  [(with_error /.index_cannot_be_repeated
+                                     (<exchange> [0 0]))]
+
+                                  [/.exchange_pure]
+                                  [/.exchange_sync]
+                                  [/.exchange_async]
+                                  )))))
           )))