diff --git a/anselme/ast/Branched.lua b/anselme/ast/Branched.lua
index b4d1857..563f7fd 100644
--- a/anselme/ast/Branched.lua
+++ b/anselme/ast/Branched.lua
@@ -4,7 +4,8 @@
 
 local ast = require("anselme.ast")
 
-local Branched = ast.abstract.Runtime {
+local Branched
+Branched = ast.abstract.Runtime {
 	type = "branched",
 	mutable = true,
 
@@ -53,6 +54,16 @@ local Branched = ast.abstract.Runtime {
 
 	_eval = function(self, state)
 		return self:get(state)
+	end,
+
+	-- serialize/deserialize in current branch and discard other branches
+	_serialize = function(self)
+		local state = require("anselme.serializer_state")
+		return self:get(state)
+	end,
+	_deserialize = function(self)
+		local state = require("anselme.serializer_state")
+		return Branched:new(state, self)
 	end
 }
 
diff --git a/anselme/state/State.lua b/anselme/state/State.lua
index 5d9390c..18b670b 100644
--- a/anselme/state/State.lua
+++ b/anselme/state/State.lua
@@ -114,13 +114,18 @@ State = class {
 	-- This can be loaded back later using `:load`.
 	save = function(self)
 		local struct = persistent_manager:get_struct(self)
-		return binser.serialize(anselme.versions.save, struct)
+		package.loaded["anselme.serializer_state"] = self
+		local r = binser.serialize(anselme.versions.save, struct)
+		package.loaded["anselme.serializer_state"] = nil
+		return r
 	end,
 	--- Load a string generated by `:save`.
 	--
 	-- Variables that already exist will be overwritten with the loaded data.
 	load = function(self, save)
+		package.loaded["anselme.serializer_state"] = self
 		local version, struct = binser.deserializeN(save, 2)
+		package.loaded["anselme.serializer_state"] = nil
 		if version ~= anselme.versions.save then print("Loading a save file generated by a different Anselme version, things may break!") end
 		for key, val in struct:iter() do
 			persistent_manager:set(self, key, val)
diff --git a/anselme/stdlib/closure.lua b/anselme/stdlib/closure.lua
index 5e5e010..7265c80 100644
--- a/anselme/stdlib/closure.lua
+++ b/anselme/stdlib/closure.lua
@@ -10,7 +10,7 @@ return {
 	{
 		"defined", "(c::function, s::string)",
 		function(state, c, s)
-			return Boolean:new(c.scope:defined_in_current_strict(state, s:to_identifier()))
+			return Boolean:new(c.scope:defined_in_current(state, s:to_identifier()))
 		end
 	},
 	{