diff --git a/lib/farmbot/celery_script/ast/ast.ex b/lib/farmbot/celery_script/ast/ast.ex
index a4583c8e..7c5cce60 100644
--- a/lib/farmbot/celery_script/ast/ast.ex
+++ b/lib/farmbot/celery_script/ast/ast.ex
@@ -4,21 +4,6 @@ defmodule Farmbot.CeleryScript.AST do
   Ast nodes.
   """
 
-  defmodule Meta do
-    @moduledoc "Metadata about an AST node."
-    defstruct [precompiled: false, encoded: nil]
-    @type t :: %__MODULE__{
-      precompiled: boolean,
-      encoded: binary
-    }
-
-    def new(ast) do
-      bin = Map.from_struct(ast) |> Map.delete(:__meta__) |> Poison.encode! 
-      encoded = :crypto.hash(:md5, bin) |> Base.encode16()
-      struct(__MODULE__, encoded: encoded)
-    end
-  end
-
   alias Farmbot.CeleryScript.Error
 
   @typedoc """
@@ -30,8 +15,7 @@ defmodule Farmbot.CeleryScript.AST do
   Type for CeleryScript Ast's.
   """
   @type t :: %__MODULE__{
-          __meta__: Meta.t,
-          uid: binary,
+          compile_meta: map | nil,
           args: args,
           body: [t, ...],
           kind: String.t(),
@@ -39,14 +23,11 @@ defmodule Farmbot.CeleryScript.AST do
         }
 
   @enforce_keys [:args, :body, :kind]
-  defstruct [
-    kind: nil,
-    uid: nil,
-    args: %{},
-    body: [],
-    comment: nil,
-    __meta__: nil
-  ]
+  defstruct kind: nil,
+            compile_meta: nil,
+            args: %{},
+            body: [],
+            comment: nil
 
   @doc """
   Parses json and traverses the tree and turns everything can
@@ -58,10 +39,7 @@ defmodule Farmbot.CeleryScript.AST do
   def parse(%{"kind" => kind, "args" => args} = thing) do
     body = thing["body"] || []
     comment = thing["comment"]
-    uid = thing["uuid"] || generate_uid()
-    before_meta = %__MODULE__{kind: kind, args: parse_args(args), body: parse(body), comment: comment, uid: uid}
-    meta = thing["__meta__"] || Meta.new(before_meta)
-    %{before_meta | __meta__: meta}
+    %__MODULE__{kind: kind, args: parse_args(args), body: parse(body), comment: comment}
   end
 
   def parse(%{__struct__: _} = thing) do
@@ -71,10 +49,7 @@ defmodule Farmbot.CeleryScript.AST do
   def parse(%{kind: kind, args: args} = thing) do
     body = thing[:body] || []
     comment = thing[:comment]
-    uid = thing[:uid] || generate_uid()
-    before_meta = %__MODULE__{kind: kind, body: parse(body), args: parse_args(args), comment: comment, uid: uid}
-    meta = thing[:__meta__] || Meta.new(before_meta)
-    %{before_meta | __meta__: meta}
+    %__MODULE__{kind: kind, body: parse(body), args: parse_args(args), comment: comment}
   end
 
   # You can give a list of nodes.
@@ -102,16 +77,4 @@ defmodule Farmbot.CeleryScript.AST do
       end
     end)
   end
-
-  @doc """
-  Creates a new AST node. No validation is preformed on this other than making
-  sure its syntax is valid.
-  """
-  def create(kind, args, body) when is_map(args) and is_list(body) do
-    %__MODULE__{kind: kind, args: args, body: body}
-  end
-
-  defp generate_uid do
-    UUID.uuid1 |> String.split("-") |> List.first
-  end
 end
diff --git a/lib/farmbot/celery_script/ast/compile_error.ex b/lib/farmbot/celery_script/ast/compiler/compile_error.ex
similarity index 62%
rename from lib/farmbot/celery_script/ast/compile_error.ex
rename to lib/farmbot/celery_script/ast/compiler/compile_error.ex
index 20e3d240..863a0080 100644
--- a/lib/farmbot/celery_script/ast/compile_error.ex
+++ b/lib/farmbot/celery_script/ast/compiler/compile_error.ex
@@ -1,4 +1,4 @@
-defmodule Farmbot.CeleryScript.AST.CompileError do
+defmodule Farmbot.CeleryScript.AST.Compiler.CompileError do
   defexception [:message]
 
   def exception(message) do
diff --git a/lib/farmbot/celery_script/ast/compiler/compiler.ex b/lib/farmbot/celery_script/ast/compiler/compiler.ex
index 14c300b8..0f0d6858 100644
--- a/lib/farmbot/celery_script/ast/compiler/compiler.ex
+++ b/lib/farmbot/celery_script/ast/compiler/compiler.ex
@@ -1,87 +1,82 @@
 defmodule Farmbot.CeleryScript.AST.Compiler do
   require Logger
-  alias Farmbot.CeleryScript.AST
-  alias Farmbot.CeleryScript.AST.CompileError
+  alias Farmbot.CeleryScript.AST.Compiler.CompileError
   alias Farmbot.CeleryScript.VirtualMachine.InstructionSet
-  import Farmbot.CeleryScript.AST.Compiler.Utils
 
-  def compile(ast, instrs) do
-    compiler_debug_log(
-      "#{Farmbot.DebugLog.color(:YELLOW)}BEGIN COMPILE: #{inspect(ast)}#{
-        Farmbot.DebugLog.color(:NC)
-      }"
-    )
-    compiler_debug_log_begin_step(ast, "ensure_implementation")
-    ast = ensure_implementation!(ast, instrs)
-    compiler_debug_log_complete_step(ast, "ensure_implementation")
-    compiler_debug_log_begin_step(ast, "precompile")
-    {state, ast} = precompile!(ast, instrs)
-    compiler_debug_log(Map.keys(state) |> Enum.join("\n\n"))
-    compiler_debug_log_complete_step(ast, "precompile")
-    ast
+  def compile(ast, %InstructionSet{} = instruction_set) do
+    res = ast
+    |> tag(:precompile)
+    |> ensure_impl(instruction_set)
+    |> precompile(instruction_set, [])
+    require IEx; IEx.pry
   end
 
-  def ensure_implementation!(%AST{kind: kind, body: []} = ast, instrs) do
-    :ok = do_ensure(kind, instrs)
-    ast
+  def tag(ast, step) do
+    %{ast | compile_meta: Map.put(ast.compile_meta || %{}, :step, step), body: tag_body(ast.body, step)}
   end
 
-  def ensure_implementation!(%AST{kind: kind, body: body} = ast, instrs) do
-    :ok = do_ensure(kind, instrs)
-    ensure_implementation!(body, instrs)
-    ast
+  defp tag_body(body, step, acc \\ [])
+
+  defp tag_body([ast | rest], step, acc) do
+    tag_body(rest, step, [tag(ast, step) | acc])
   end
 
-  def ensure_implementation!([%AST{kind: kind, body: body} | next], instrs) do
-    :ok = do_ensure(kind, instrs)
-    ensure_implementation!(body, instrs)
-    ensure_implementation!(next, instrs)
-  end
+  defp tag_body([], _step, acc), do: Enum.reverse(acc)
 
-  def ensure_implementation!([], _), do: :ok
-
-  defp do_ensure(kind, instrs) do
-    compiler_debug_log(kind, "ensure implementation")
-    impl = instrs[kind] || raise CompileError, "No implementation for #{kind}"
-    if Code.ensure_loaded?(impl) do
-      :ok
-    else
-      raise CompileError, "Implementation module: #{impl} is not loaded."
+  def ensure_impl(ast, %InstructionSet{} = instruction_set) do
+    unless instruction_set[ast.kind] do
+      raise CompileError, "#{ast.kind} has no implementation."
     end
+
+    unless Code.ensure_loaded?(instruction_set[ast.kind]) do
+      raise CompileError, "#{ast.kind} implementation could not be loaded."
+    end
+
+    %{ast | body: ensure_impl_body(ast.body, instruction_set)}
   end
 
-  # sequence
-  # -> execute_sequence
-  #    -> move_abs
+  def ensure_impl_body(body, instruction_set, acc \\ [])
 
-  def precompile!(ast, instrs, state \\ %{}) do
-    impl = instrs[ast.kind]
-    if state[ast.__meta__.encoded] do
-      compiler_debug_log("#{inspect ast} compiled")
-      {state, ast}
+  def ensure_impl_body([ast | rest], %InstructionSet{} = instruction_set, acc) do
+    ensure_impl_body(rest, instruction_set, [ensure_impl(ast, instruction_set) | acc])
+  end
+
+  def ensure_impl_body([], %InstructionSet{} = _instruction_set, acc), do: Enum.reverse(acc)
+
+  def precompile(ast, %InstructionSet{} = instruction_set, cache) do
+    md5 = :crypto.hash(:md5, Poison.encode!(ast)) |> Base.encode16
+    IO.puts "precompiling: #{inspect ast}: #{inspect ast.compile_meta} => #{md5}"
+    IO.inspect cache
+    if md5 in cache do
+      ast
     else
-      case impl.precompile(ast) do
-        {:ok, res} ->
-          res = %{res | __meta__: %{res.__meta__ | precompiled: true}}
-          state = Map.put(state, res.__meta__.encoded, res)
-          {state, ast} = precompile!(res, instrs, state)
-          {state, body} = precompile_body(ast.body, instrs, state)
-          %{ast | body: body} |> precompile!(instrs, state)
+      cache = [md5 | cache]
+      case instruction_set[ast.kind].precompile(ast) do
         {:error, reason} -> raise CompileError, reason
+        {:ok, precompiled} ->
+          precompiled = %{precompiled | body: precompile_body(precompiled.body, instruction_set, cache)}
+          IO.inspect precompiled.compile_meta
+          case precompiled.compile_meta do
+            nil ->
+              precompiled
+              |> tag(:precompile)
+              |> ensure_impl(instruction_set)
+              |> precompile(instruction_set, cache)
+              |> tag(:compile)
+            %{step: :precompile} -> tag(precompiled, :compile)
+          end
       end
     end
+
   end
 
-  defp precompile_body(body, instrs, state, acc \\ [])
+  def precompile_body(body, instruction_set, cache, acc \\ [])
 
-  defp precompile_body([ast | rest], instrs, state, acc) do
-    {state, ast} = precompile!(ast, instrs, state)
-    acc = [ast | acc]
-    precompile_body(rest, instrs, state, acc)
+  def precompile_body([ast | rest], %InstructionSet{} = instruction_set, cache, acc) do
+    precompile_body(rest, instruction_set, cache, [precompile(ast, instruction_set, cache) | acc])
   end
 
-  defp precompile_body([], instrs, state, acc) do
-    {state, Enum.reverse(acc)}
-  end
+  def precompile_body([], %InstructionSet{} = _instruction_set, _cache, acc), do: Enum.reverse(acc)
 end
+
 # Farmbot.HTTP.get!("/api/sequences/2") |> Map.get(:body) |> Poison.decode! |> Farmbot.CeleryScript.AST.parse |> Farmbot.CeleryScript.VirtualMachine.execute
diff --git a/lib/farmbot/celery_script/ast/compiler/utils.ex b/lib/farmbot/celery_script/ast/compiler/utils.ex
deleted file mode 100644
index f547b4c9..00000000
--- a/lib/farmbot/celery_script/ast/compiler/utils.ex
+++ /dev/null
@@ -1,59 +0,0 @@
-defmodule Farmbot.CeleryScript.AST.Compiler.Utils do
-  alias Farmbot.CeleryScript.VirtualMachine.InstructionSet
-  def compiler_debug_log(kind, msg) do
-    msg =
-      "#{format_kind(kind)}" <>
-        "#{Farmbot.DebugLog.color(:LIGHT_GREEN)}[ " <> msg <> " ]#{Farmbot.DebugLog.color(:NC)}"
-
-    compiler_debug_log(msg)
-  end
-
-  def compiler_debug_log_begin_step(ast, step) do
-    compiler_debug_log(
-      "#{Farmbot.DebugLog.color(:YELLOW)}[ #{inspect ast} ] " <> # "#{ast.__meta__.encoded} " <>
-      "#{Farmbot.DebugLog.color(:LIGHT_GREEN)}begin step: #{Farmbot.DebugLog.color(:YELLOW)}[ #{step} ]#{
-        Farmbot.DebugLog.color(:NC)
-      }"
-    )
-  end
-
-  def compiler_debug_log_complete_step(ast, step) do
-    compiler_debug_log(
-      "#{Farmbot.DebugLog.color(:YELLOW)}[ #{inspect ast} ] " <>#  "#{ast.__meta__.encoded} " <>
-      "#{Farmbot.DebugLog.color(:LIGHT_GREEN)}complete step: #{Farmbot.DebugLog.color(:YELLOW)}[ #{step} ]#{
-        Farmbot.DebugLog.color(:NC)
-      }"
-    )
-  end
-
-  def compiler_debug_log(msg) do
-    IO.puts(msg)
-  end
-
-  kinds = Map.keys(struct(InstructionSet)) -- [:__struct__]
-
-  max_chars =
-    Enum.reduce(kinds, 0, fn kind, acc ->
-      num_chars = to_charlist(kind) |> Enum.count()
-
-      if num_chars > acc do
-        num_chars
-      else
-        acc
-      end
-    end)
-
-  for kind <- kinds do
-    num_chars = to_charlist(kind) |> Enum.count()
-    pad = max_chars - num_chars
-    # "#{String.duplicate(" ", pad)} - " <>
-    res =
-      "#{Farmbot.DebugLog.color(:LIGHT_CYAN)}" <>
-        "[ " <>
-        "#{Farmbot.DebugLog.color(:CYAN)}#{kind}" <>
-        "#{String.duplicate(" ", pad)}" <>
-        "#{Farmbot.DebugLog.color(:LIGHT_CYAN)} ]" <> "#{Farmbot.DebugLog.color(:NC)} - "
-
-    def format_kind(unquote(kind |> to_string())), do: unquote(res)
-  end
-end
diff --git a/lib/farmbot/celery_script/ast/inspect.ex b/lib/farmbot/celery_script/ast/inspect.ex
index f7daf111..9fcc1911 100644
--- a/lib/farmbot/celery_script/ast/inspect.ex
+++ b/lib/farmbot/celery_script/ast/inspect.ex
@@ -1,5 +1,5 @@
 defimpl Inspect, for: Farmbot.CeleryScript.AST do
   def inspect(ast, _opts) do
-    "#CeleryScript[#{ast.uid}]<#{ast.kind}: #{inspect(Map.keys(ast.args))}>"
+    "#CeleryScript<#{ast.kind}: #{inspect(Map.keys(ast.args))}>"
   end
 end