diff --git a/lib/orb/constants.ex b/lib/orb/constants.ex
index 39d0570..c03fc14 100644
--- a/lib/orb/constants.ex
+++ b/lib/orb/constants.ex
@@ -105,6 +105,13 @@ defmodule Orb.Constants do
   defmodule NulTerminatedString do
     defstruct memory_offset: nil, string: nil, type: Orb.I32.String
 
+    def empty() do
+      %__MODULE__{
+        memory_offset: 0x0,
+        string: ""
+      }
+    end
+
     defimpl Orb.ToWat do
       def to_wat(%Orb.Constants.NulTerminatedString{memory_offset: memory_offset}, indent) do
         [
@@ -126,10 +133,12 @@ defmodule Orb.Constants do
   def expand_if_needed(value) when is_binary(value), do: expand_string!(value)
   def expand_if_needed(value) when is_list(value), do: :lists.map(&expand_if_needed/1, value)
   def expand_if_needed(value) when is_struct(value, Orb.IfElse), do: Orb.IfElse.expand(value)
+
   def expand_if_needed(%_{body: _} = struct) do
     body = expand_if_needed(struct.body)
     %{struct | body: body}
   end
+
   def expand_if_needed(value), do: value
 
   defp expand_string!(string) when is_binary(string) do
diff --git a/lib/orb/global.ex b/lib/orb/global.ex
index 1178e58..8ae3604 100644
--- a/lib/orb/global.ex
+++ b/lib/orb/global.ex
@@ -75,13 +75,23 @@ defmodule Orb.Global do
     end
   end
 
+  def expand!(%Orb.Global{type: Orb.I32.String, initial_value: ""} = global) do
+    %Orb.Global{global | type: Orb.I32.String, initial_value: Orb.Constants.NulTerminatedString.empty()}
+  end
+
   def expand!(%Orb.Global{type: Orb.I32.String, initial_value: string} = global) do
-    %Orb.Global{global | type: :i32, initial_value: Orb.Constants.expand_if_needed(string)}
+    %Orb.Global{
+      global
+      | type: Orb.I32.String,
+        initial_value: Orb.Constants.expand_if_needed(string)
+    }
   end
 
   def expand!(%Orb.Global{} = global), do: global
 
   defimpl Orb.ToWat do
+    import Orb.ToWat.Helpers
+
     def to_wat(
           %Orb.Global{
             name: name,
@@ -101,8 +111,8 @@ defmodule Orb.Global do
         end,
         " ",
         case mutability do
-          :readonly -> to_string(type)
-          :mutable -> ["(mut ", to_string(type), ?)]
+          :readonly -> do_type(type)
+          :mutable -> ["(mut ", do_type(type), ?)]
         end,
         " ",
         Orb.ToWat.to_wat(initial_value, ""),
diff --git a/test/orb_test.exs b/test/orb_test.exs
index 968771b..04c435a 100644
--- a/test/orb_test.exs
+++ b/test/orb_test.exs
@@ -85,6 +85,7 @@ defmodule OrbTest do
         global :mutable do
           @language "en"
           @mime_type "text/html"
+          @empty ""
         end
 
         defw mime_type_constant, I32.String do
@@ -109,6 +110,7 @@ defmodule OrbTest do
                (global $five_quarters f32 (f32.const 1.25))
                (global $language (mut i32) (i32.const 255))
                (global $mime_type (mut i32) (i32.const 258))
+               (global $empty (mut i32) (i32.const 0))
                (data (i32.const 258) \"text/html\")
                (data (i32.const 255) \"en\")
                (func $mime_type_constant (export \"mime_type_constant\") (result i32)