diff --git a/lib/spitfire.ex b/lib/spitfire.ex
index d130be4..439e925 100644
--- a/lib/spitfire.ex
+++ b/lib/spitfire.ex
@@ -142,6 +142,8 @@ defmodule Spitfire do
   rescue
     NoFuelRemaining ->
       {:error, :no_fuel_remaining}
+  after
+    Process.delete(:comma_list_parsers)
   end
 
   def parse!(code, opts \\ []) do
@@ -1379,6 +1381,8 @@ defmodule Spitfire do
     aliases = [alias | aliases]
 
     {{:__aliases__, [{:last, Process.get(:alias_last_meta)} | meta], aliases}, parser}
+  after
+    Process.delete(:alias_last_meta)
   end
 
   defp parse_bitstring(%{current_token: {:"<<", _}} = parser) do
diff --git a/lib/spitfire/env.ex b/lib/spitfire/env.ex
index 75996e8..921fd14 100644
--- a/lib/spitfire/env.ex
+++ b/lib/spitfire/env.ex
@@ -49,6 +49,8 @@ defmodule Spitfire.Env do
       )
 
     {ast, state, env, cursor_env}
+  after
+    Process.delete(:cursor_env)
   end
 
   defp expand({:__cursor__, _meta, _} = node, state, env) do