diff --git a/plugin/src/DevSettings.lua b/plugin/src/DevSettings.lua
index 8edf7efb..060742c2 100644
--- a/plugin/src/DevSettings.lua
+++ b/plugin/src/DevSettings.lua
@@ -1,10 +1,27 @@
 local Config = require(script.Parent.Config)
 
+local Environment = {
+	User = "User",
+	Dev = "Dev",
+	Test = "Test",
+}
+
 local VALUES = {
 	LogLevel = {
 		type = "IntValue",
-		defaultUserValue = 2,
-		defaultDevValue = 3,
+		values = {
+			[Environment.User] = 2,
+			[Environment.Dev] = 3,
+			[Environment.Test] = 3,
+		},
+	},
+	TypecheckingEnabled = {
+		type = "BoolValue",
+		values = {
+			[Environment.User] = false,
+			[Environment.Dev] = true,
+			[Environment.Test] = true,
+		},
 	},
 }
 
@@ -42,7 +59,9 @@ local function setStoredValue(name, kind, value)
 	object.Value = value
 end
 
-local function createAllValues()
+local function createAllValues(environment)
+	assert(Environment[environment] ~= nil, "Invalid environment")
+
 	valueContainer = getValueContainer()
 
 	if valueContainer == nil then
@@ -52,20 +71,57 @@ local function createAllValues()
 	end
 
 	for name, value in pairs(VALUES) do
-		setStoredValue(name, value.type, value.defaultDevValue)
+		setStoredValue(name, value.type, value.values[environment])
 	end
 end
 
-_G[("ROJO_%s_DEV_CREATE"):format(Config.codename:upper())] = createAllValues
+local function getValue(name)
+	assert(VALUES[name] ~= nil, "Invalid DevSettings name")
+
+	local stored = getStoredValue(name)
+
+	if stored ~= nil then
+		return stored
+	end
+
+	return VALUES[name].values[Environment.User]
+end
 
 local DevSettings = {}
 
+function DevSettings:createDevSettings()
+	createAllValues(Environment.Dev)
+end
+
+function DevSettings:createTestSettings()
+	createAllValues(Environment.Test)
+end
+
+function DevSettings:hasChangedValues()
+	return valueContainer ~= nil
+end
+
+function DevSettings:resetValues()
+	if valueContainer then
+		valueContainer:Destroy()
+		valueContainer = nil
+	end
+end
+
 function DevSettings:isEnabled()
 	return valueContainer ~= nil
 end
 
 function DevSettings:getLogLevel()
-	return getStoredValue("LogLevel") or VALUES.LogLevel.defaultUserValue
+	return getValue("LogLevel")
+end
+
+function DevSettings:shouldTypecheck()
+	return getValue("TypecheckingEnabled")
+end
+
+function _G.ROJO_DEV_CREATE()
+	DevSettings:createDevSettings()
 end
 
 return DevSettings
\ No newline at end of file
diff --git a/plugin/src/Reconciler.lua b/plugin/src/Reconciler.lua
index d63bfddd..58eb4182 100644
--- a/plugin/src/Reconciler.lua
+++ b/plugin/src/Reconciler.lua
@@ -1,7 +1,10 @@
+local t = require(script.Parent.Parent.t)
+
 local InstanceMap = require(script.Parent.InstanceMap)
 local Logging = require(script.Parent.Logging)
 local setCanonicalProperty = require(script.Parent.setCanonicalProperty)
 local rojoValueToRobloxValue = require(script.Parent.rojoValueToRobloxValue)
+local Types = require(script.Parent.Types)
 
 local Reconciler = {}
 Reconciler.__index = Reconciler
@@ -24,11 +27,18 @@ function Reconciler:applyUpdate(requestedIds, virtualInstancesById)
 	end
 end
 
+local reconcileSchema = Types.ifEnabled(t.tuple(
+	t.map(t.string, Types.VirtualInstance),
+	t.string,
+	t.Instance
+))
 --[[
 	Update an existing instance, including its properties and children, to match
 	the given information.
 ]]
 function Reconciler:reconcile(virtualInstancesById, id, instance)
+	assert(reconcileSchema(virtualInstancesById, id, instance))
+
 	local virtualInstance = virtualInstancesById[id]
 
 	-- If an instance changes ClassName, we assume it's very different. That's
@@ -121,7 +131,15 @@ function Reconciler:__shouldClearUnknownChildren(virtualInstance)
 	end
 end
 
+local reifySchema = Types.ifEnabled(t.tuple(
+	t.map(t.string, Types.VirtualInstance),
+	t.string,
+	t.Instance
+))
+
 function Reconciler:__reify(virtualInstancesById, id, parent)
+	assert(reifySchema(virtualInstancesById, id, parent))
+
 	local virtualInstance = virtualInstancesById[id]
 
 	local instance = Instance.new(virtualInstance.ClassName)
@@ -142,7 +160,15 @@ function Reconciler:__reify(virtualInstancesById, id, parent)
 	return instance
 end
 
+local applyUpdatePieceSchema = Types.ifEnabled(t.tuple(
+	t.string,
+	t.map(t.string, t.boolean),
+	t.map(t.string, Types.VirtualInstance)
+))
+
 function Reconciler:__applyUpdatePiece(id, visitedIds, virtualInstancesById)
+	assert(applyUpdatePieceSchema(id, visitedIds, virtualInstancesById))
+
 	if visitedIds[id] then
 		return
 	end
diff --git a/plugin/src/Types.lua b/plugin/src/Types.lua
new file mode 100644
index 00000000..f182d60a
--- /dev/null
+++ b/plugin/src/Types.lua
@@ -0,0 +1,36 @@
+local t = require(script.Parent.Parent.t)
+
+local DevSettings = require(script.Parent.DevSettings)
+
+local VirtualValue = t.interface({
+	Type = t.string,
+	Value = t.optional(t.any),
+})
+
+local VirtualMetadata = t.interface({
+	ignoreUnknownInstances = t.optional(t.boolean),
+})
+
+local VirtualInstance = t.interface({
+	Name = t.string,
+	ClassName = t.string,
+	Properties = t.map(t.string, VirtualValue),
+	Metadata = t.optional(VirtualMetadata)
+})
+
+local function ifEnabled(innerCheck)
+	return function(...)
+		if DevSettings:shouldTypecheck() then
+			return innerCheck(...)
+		else
+			return true
+		end
+	end
+end
+
+return {
+	ifEnabled = ifEnabled,
+	VirtualInstance = VirtualInstance,
+	VirtualMetadata = VirtualMetadata,
+	VirtualValue = VirtualValue,
+}
\ No newline at end of file
diff --git a/plugin/testBootstrap.server.lua b/plugin/testBootstrap.server.lua
index 4d10558a..81ed88b2 100644
--- a/plugin/testBootstrap.server.lua
+++ b/plugin/testBootstrap.server.lua
@@ -1,2 +1,19 @@
-local TestEZ = require(game.ReplicatedStorage.TestEZ)
-TestEZ.TestBootstrap:run({game.ReplicatedStorage.Rojo.Plugin})
\ No newline at end of file
+local ReplicatedStorage = game:GetService("ReplicatedStorage")
+
+local TestEZ = require(ReplicatedStorage.TestEZ)
+
+local Rojo = ReplicatedStorage.Rojo
+
+local DevSettings = require(Rojo.Plugin.DevSettings)
+
+local setDevSettings = not DevSettings:hasChangedValues()
+
+if setDevSettings then
+	DevSettings:createTestSettings()
+end
+
+TestEZ.TestBootstrap:run({Rojo.Plugin})
+
+if setDevSettings then
+	DevSettings:resetValues()
+end
\ No newline at end of file