diff --git a/icinga-app/icinga.cpp b/icinga-app/icinga.cpp
index 05f4944f6fa..be8a10ae4c4 100644
--- a/icinga-app/icinga.cpp
+++ b/icinga-app/icinga.cpp
@@ -280,17 +280,6 @@ static int Main()
 #endif /* RLIMIT_STACK */
 	}
 
-	/* Calculate additional global constants. */
-	ScriptGlobal::Set("System.PlatformKernel", Utility::GetPlatformKernel(), true);
-	ScriptGlobal::Set("System.PlatformKernelVersion", Utility::GetPlatformKernelVersion(), true);
-	ScriptGlobal::Set("System.PlatformName", Utility::GetPlatformName(), true);
-	ScriptGlobal::Set("System.PlatformVersion", Utility::GetPlatformVersion(), true);
-	ScriptGlobal::Set("System.PlatformArchitecture", Utility::GetPlatformArchitecture(), true);
-
-	ScriptGlobal::Set("System.BuildHostName", ICINGA_BUILD_HOST_NAME, true);
-	ScriptGlobal::Set("System.BuildCompilerName", ICINGA_BUILD_COMPILER_NAME, true);
-	ScriptGlobal::Set("System.BuildCompilerVersion", ICINGA_BUILD_COMPILER_VERSION, true);
-
 	if (!autocomplete)
 		Application::SetResourceLimits();
 
diff --git a/lib/base/function.hpp b/lib/base/function.hpp
index fa1ce92bdbe..d52a230a1ee 100644
--- a/lib/base/function.hpp
+++ b/lib/base/function.hpp
@@ -60,28 +60,28 @@ class Function final : public ObjectImpl<Function>
 	INITIALIZE_ONCE_WITH_PRIORITY([]() { \
 		Function::Ptr sf = new icinga::Function(#ns "#" #name, callback, String(args).Split(":"), false); \
 		Namespace::Ptr nsp = ScriptGlobal::Get(#ns); \
-		nsp->SetAttribute(#name, new ConstEmbeddedNamespaceValue(sf)); \
+		nsp->Set(#name, sf, true); \
 	}, InitializePriority::RegisterFunctions)
 
 #define REGISTER_SAFE_FUNCTION(ns, name, callback, args) \
 	INITIALIZE_ONCE_WITH_PRIORITY([]() { \
 		Function::Ptr sf = new icinga::Function(#ns "#" #name, callback, String(args).Split(":"), true); \
 		Namespace::Ptr nsp = ScriptGlobal::Get(#ns); \
-		nsp->SetAttribute(#name, new ConstEmbeddedNamespaceValue(sf)); \
+		nsp->Set(#name, sf, true); \
 	}, InitializePriority::RegisterFunctions)
 
 #define REGISTER_FUNCTION_NONCONST(ns, name, callback, args) \
 	INITIALIZE_ONCE_WITH_PRIORITY([]() { \
 		Function::Ptr sf = new icinga::Function(#ns "#" #name, callback, String(args).Split(":"), false); \
 		Namespace::Ptr nsp = ScriptGlobal::Get(#ns); \
-		nsp->SetAttribute(#name, new EmbeddedNamespaceValue(sf)); \
+		nsp->Set(#name, sf, false); \
 	}, InitializePriority::RegisterFunctions)
 
 #define REGISTER_SAFE_FUNCTION_NONCONST(ns, name, callback, args) \
 	INITIALIZE_ONCE_WITH_PRIORITY([]() { \
 		Function::Ptr sf = new icinga::Function(#ns "#" #name, callback, String(args).Split(":"), true); \
 		Namespace::Ptr nsp = ScriptGlobal::Get(#ns); \
-		nsp->SetAttribute(#name, new EmbeddedNamespaceValue(sf)); \
+		nsp->SetAttribute(#name, sf, false); \
 	}, InitializePriority::RegisterFunctions)
 
 }
diff --git a/lib/base/initialize.hpp b/lib/base/initialize.hpp
index 94dedfaf2a9..adc995fe1b9 100644
--- a/lib/base/initialize.hpp
+++ b/lib/base/initialize.hpp
@@ -25,6 +25,7 @@ enum class InitializePriority {
 	RegisterTypes,
 	EvaluateConfigFragments,
 	Default,
+	FreezeNamespaces,
 };
 
 #define I2_TOKENPASTE(x, y) x ## y
diff --git a/lib/base/json-script.cpp b/lib/base/json-script.cpp
index cb3c03392bb..90595c88f10 100644
--- a/lib/base/json-script.cpp
+++ b/lib/base/json-script.cpp
@@ -24,5 +24,5 @@ INITIALIZE_ONCE([]() {
 	jsonNS->Freeze();
 
 	Namespace::Ptr systemNS = ScriptGlobal::Get("System");
-	systemNS->SetAttribute("Json", new ConstEmbeddedNamespaceValue(jsonNS));
+	systemNS->Set("Json", jsonNS, true);
 });
diff --git a/lib/base/json.cpp b/lib/base/json.cpp
index 6937f0a9bda..59066e78760 100644
--- a/lib/base/json.cpp
+++ b/lib/base/json.cpp
@@ -95,7 +95,7 @@ void EncodeNamespace(JsonEncoder<prettyPrint>& stateMachine, const Namespace::Pt
 	ObjectLock olock(ns);
 	for (const Namespace::Pair& kv : ns) {
 		stateMachine.Key(Utility::ValidateUTF8(kv.first));
-		Encode(stateMachine, kv.second->Get());
+		Encode(stateMachine, kv.second.Val);
 	}
 
 	stateMachine.EndObject();
diff --git a/lib/base/logger.cpp b/lib/base/logger.cpp
index 0be7279b2c0..38a2c6721b4 100644
--- a/lib/base/logger.cpp
+++ b/lib/base/logger.cpp
@@ -40,11 +40,11 @@ std::mutex Logger::m_UpdateMinLogSeverityMutex;
 Atomic<LogSeverity> Logger::m_MinLogSeverity (LogDebug);
 
 INITIALIZE_ONCE([]() {
-	ScriptGlobal::Set("System.LogDebug", LogDebug, true);
-	ScriptGlobal::Set("System.LogNotice", LogNotice, true);
-	ScriptGlobal::Set("System.LogInformation", LogInformation, true);
-	ScriptGlobal::Set("System.LogWarning", LogWarning, true);
-	ScriptGlobal::Set("System.LogCritical", LogCritical, true);
+	ScriptGlobal::Set("System.LogDebug", LogDebug);
+	ScriptGlobal::Set("System.LogNotice", LogNotice);
+	ScriptGlobal::Set("System.LogInformation", LogInformation);
+	ScriptGlobal::Set("System.LogWarning", LogWarning);
+	ScriptGlobal::Set("System.LogCritical", LogCritical);
 });
 
 /**
diff --git a/lib/base/math-script.cpp b/lib/base/math-script.cpp
index dbc2fb28549..6cd7b0eb4f7 100644
--- a/lib/base/math-script.cpp
+++ b/lib/base/math-script.cpp
@@ -180,5 +180,5 @@ INITIALIZE_ONCE([]() {
 	mathNS->Freeze();
 
 	Namespace::Ptr systemNS = ScriptGlobal::Get("System");
-	systemNS->SetAttribute("Math", new ConstEmbeddedNamespaceValue(mathNS));
+	systemNS->Set("Math", mathNS, true);
 });
diff --git a/lib/base/namespace-script.cpp b/lib/base/namespace-script.cpp
index 29d23a000d6..deaae7dec2d 100644
--- a/lib/base/namespace-script.cpp
+++ b/lib/base/namespace-script.cpp
@@ -63,7 +63,7 @@ static Array::Ptr NamespaceValues()
 	ArrayData values;
 	ObjectLock olock(self);
 	for (const Namespace::Pair& kv : self) {
-		values.push_back(kv.second->Get());
+		values.push_back(kv.second.Val);
 	}
 	return new Array(std::move(values));
 }
diff --git a/lib/base/namespace.cpp b/lib/base/namespace.cpp
index d9947f1f340..cb7c872bd7c 100644
--- a/lib/base/namespace.cpp
+++ b/lib/base/namespace.cpp
@@ -25,32 +25,47 @@ Namespace::Namespace(bool constValues)
 
 Value Namespace::Get(const String& field) const
 {
-	ObjectLock olock(this);
-
 	Value value;
-	if (!GetOwnField(field, &value))
+	if (!Get(field, &value))
 		BOOST_THROW_EXCEPTION(ScriptError("Namespace does not contain field '" + field + "'"));
 	return value;
 }
 
 bool Namespace::Get(const String& field, Value *value) const
 {
-	ObjectLock olock(this);
+	auto lock(ReadLockUnlessFrozen());
 
-	auto nsVal = GetAttribute(field);
+	auto nsVal = m_Data.find(field);
 
-	if (!nsVal)
+	if (nsVal == m_Data.end()) {
 		return false;
+	}
 
-	*value =  nsVal->Get(DebugInfo());
+	*value = nsVal->second.Val;
 	return true;
 }
 
-void Namespace::Set(const String& field, const Value& value, bool overrideFrozen)
+void Namespace::Set(const String& field, const Value& value, bool isConst, const DebugInfo& debugInfo)
 {
 	ObjectLock olock(this);
 
-	return SetFieldByName(field, value, overrideFrozen, DebugInfo());
+	if (m_Frozen) {
+		BOOST_THROW_EXCEPTION(ScriptError("Namespace is read-only and must not be modified.", debugInfo));
+	}
+
+	std::unique_lock<decltype(m_DataMutex)> dlock (m_DataMutex);
+
+	auto nsVal = m_Data.find(field);
+
+	if (nsVal == m_Data.end()) {
+		m_Data[field] = NamespaceValue{value, isConst};
+	} else {
+		if (nsVal->second.Const) {
+			BOOST_THROW_EXCEPTION(ScriptError("Constant must not be modified.", debugInfo));
+		}
+
+		nsVal->second.Val = value;
+	}
 }
 
 /**
@@ -60,39 +75,43 @@ void Namespace::Set(const String& field, const Value& value, bool overrideFrozen
  */
 size_t Namespace::GetLength() const
 {
-	ObjectLock olock(this);
+	auto lock(ReadLockUnlessFrozen());
 
 	return m_Data.size();
 }
 
 bool Namespace::Contains(const String& field) const
 {
-	ObjectLock olock(this);
+	auto lock (ReadLockUnlessFrozen());
 
-	return HasOwnField(field);
+	return m_Data.find(field) != m_Data.end();
 }
 
-void Namespace::Remove(const String& field, bool overrideFrozen)
+void Namespace::Remove(const String& field)
 {
 	ObjectLock olock(this);
 
-	if (m_Frozen && !overrideFrozen) {
+	if (m_Frozen) {
 		BOOST_THROW_EXCEPTION(ScriptError("Namespace is read-only and must not be modified."));
 	}
 
-	if (!overrideFrozen) {
-		auto attr = GetAttribute(field);
+	std::unique_lock<decltype(m_DataMutex)> dlock (m_DataMutex);
 
-		if (dynamic_pointer_cast<ConstEmbeddedNamespaceValue>(attr)) {
-			BOOST_THROW_EXCEPTION(ScriptError("Constants must not be removed."));
-		}
+	auto it = m_Data.find(field);
+
+	if (it == m_Data.end()) {
+		return;
 	}
 
-	RemoveAttribute(field);
+	if (it->second.Const) {
+		BOOST_THROW_EXCEPTION(ScriptError("Constants must not be removed."));
+	}
+
+	m_Data.erase(it);
 }
 
 /**
- * Freeze the namespace, preventing further updates unless overrideFrozen is set.
+ * Freeze the namespace, preventing further updates.
  *
  * This only prevents inserting, replacing or deleting values from the namespace. This operation has no effect on
  * objects referenced by the values, these remain mutable if they were before.
@@ -103,111 +122,45 @@ void Namespace::Freeze() {
 	m_Frozen = true;
 }
 
-void Namespace::RemoveAttribute(const String& field)
-{
-	ObjectLock olock(this);
-
-	Namespace::Iterator it;
-	it = m_Data.find(field);
-
-	if (it == m_Data.end())
-		return;
-
-	m_Data.erase(it);
-}
-
-NamespaceValue::Ptr Namespace::GetAttribute(const String& key) const
-{
-	ObjectLock olock(this);
-
-	auto it = m_Data.find(key);
-
-	if (it == m_Data.end())
-		return nullptr;
-
-	return it->second;
-}
-
-void Namespace::SetAttribute(const String& key, const NamespaceValue::Ptr& nsVal)
+std::shared_lock<std::shared_timed_mutex> Namespace::ReadLockUnlessFrozen() const
 {
-	ObjectLock olock(this);
-
-	m_Data[key] = nsVal;
+	if (m_Frozen.load(std::memory_order_relaxed)) {
+		return std::shared_lock<std::shared_timed_mutex>();
+	} else {
+		return std::shared_lock<std::shared_timed_mutex>(m_DataMutex);
+	}
 }
 
 Value Namespace::GetFieldByName(const String& field, bool, const DebugInfo& debugInfo) const
 {
-	ObjectLock olock(this);
+	auto lock (ReadLockUnlessFrozen());
 
-	auto nsVal = GetAttribute(field);
+	auto nsVal = m_Data.find(field);
 
-	if (nsVal)
-		return nsVal->Get(debugInfo);
+	if (nsVal != m_Data.end())
+		return nsVal->second.Val;
 	else
 		return GetPrototypeField(const_cast<Namespace *>(this), field, false, debugInfo); /* Ignore indexer not found errors similar to the Dictionary class. */
 }
 
 void Namespace::SetFieldByName(const String& field, const Value& value, bool overrideFrozen, const DebugInfo& debugInfo)
 {
-	ObjectLock olock(this);
-
-	auto nsVal = GetAttribute(field);
+	// The override frozen parameter is mandated by the interface but ignored here. If the namespace is frozen, this
+	// disables locking for read operations, so it must not be modified again to ensure the consistency of the internal
+	// data structures.
+	(void) overrideFrozen;
 
-	if (!nsVal) {
-		if (m_Frozen && !overrideFrozen) {
-			BOOST_THROW_EXCEPTION(ScriptError("Namespace is read-only and must not be modified.", debugInfo));
-		}
-
-		if (m_ConstValues) {
-			SetAttribute(field, new ConstEmbeddedNamespaceValue(value));
-		} else {
-			SetAttribute(field, new EmbeddedNamespaceValue(value));
-		}
-	} else {
-		nsVal->Set(value, overrideFrozen, debugInfo);
-	}
+	Set(field, value, false, debugInfo);
 }
 
 bool Namespace::HasOwnField(const String& field) const
 {
-	ObjectLock olock(this);
-
-	return GetAttribute(field) != nullptr;
+	return Contains(field);
 }
 
 bool Namespace::GetOwnField(const String& field, Value *result) const
 {
-	ObjectLock olock(this);
-
-	auto nsVal = GetAttribute(field);
-
-	if (!nsVal)
-		return false;
-
-	*result = nsVal->Get(DebugInfo());
-	return true;
-}
-
-EmbeddedNamespaceValue::EmbeddedNamespaceValue(const Value& value)
-	: m_Value(value)
-{ }
-
-Value EmbeddedNamespaceValue::Get(const DebugInfo& debugInfo) const
-{
-	return m_Value;
-}
-
-void EmbeddedNamespaceValue::Set(const Value& value, bool, const DebugInfo&)
-{
-	m_Value = value;
-}
-
-void ConstEmbeddedNamespaceValue::Set(const Value& value, bool overrideFrozen, const DebugInfo& debugInfo)
-{
-	if (!overrideFrozen)
-		BOOST_THROW_EXCEPTION(ScriptError("Constant must not be modified.", debugInfo));
-
-	EmbeddedNamespaceValue::Set(value, overrideFrozen, debugInfo);
+	return Get(field, result);
 }
 
 Namespace::Iterator Namespace::Begin()
diff --git a/lib/base/namespace.hpp b/lib/base/namespace.hpp
index 492d62f0e53..94f2055d373 100644
--- a/lib/base/namespace.hpp
+++ b/lib/base/namespace.hpp
@@ -8,42 +8,52 @@
 #include "base/shared-object.hpp"
 #include "base/value.hpp"
 #include "base/debuginfo.hpp"
+#include <atomic>
 #include <map>
 #include <vector>
 #include <memory>
+#include <shared_mutex>
 
 namespace icinga
 {
 
-struct NamespaceValue : public SharedObject
+struct NamespaceValue
 {
-	DECLARE_PTR_TYPEDEFS(NamespaceValue);
-
-	virtual Value Get(const DebugInfo& debugInfo = DebugInfo()) const = 0;
-	virtual void Set(const Value& value, bool overrideFrozen, const DebugInfo& debugInfo = DebugInfo()) = 0;
-};
-
-struct EmbeddedNamespaceValue : public NamespaceValue
-{
-	EmbeddedNamespaceValue(const Value& value);
-
-	Value Get(const DebugInfo& debugInfo) const override;
-	void Set(const Value& value, bool overrideFrozen, const DebugInfo& debugInfo) override;
-
-private:
-	Value m_Value;
+	Value Val;
+	bool Const;
 };
 
-struct ConstEmbeddedNamespaceValue : public EmbeddedNamespaceValue
-{
-	using EmbeddedNamespaceValue::EmbeddedNamespaceValue;
-
-	void Set(const Value& value, bool overrideFrozen, const DebugInfo& debugInfo) override;
-};
 
 /**
  * A namespace.
  *
+ * ## External Locking
+ *
+ * Synchronization is handled internally, so almost all functions are safe for concurrent use without external locking.
+ * The only exception to this are functions returning an iterator. To use these, the caller has to acquire an ObjectLock
+ * on the namespace. The iterators only remain valid for as long as that ObjectLock is held. Note that this also
+ * includes range-based for loops.
+ *
+ * If consistency across multiple operations is required, an ObjectLock must also be acquired to prevent concurrent
+ * modifications.
+ *
+ * ## Internal Locking
+ *
+ * Two mutex objects are involved in locking a namespace: the recursive mutex inherited from the Object class that is
+ * acquired and released using the ObjectLock class and the m_DataMutex shared mutex contained directly in the
+ * Namespace class. The ObjectLock is used to synchronize multiple write operations against each other. The shared mutex
+ * is only used to ensure the consistency of the m_Data data structure.
+ *
+ * Read operations must acquire a shared lock on m_DataMutex. This prevents concurrent writes to that data structure
+ * but still allows concurrent reads.
+ *
+ * Write operations must first obtain an ObjectLock and then a shared lock on m_DataMutex. This order is important for
+ * preventing deadlocks. The ObjectLock prevents concurrent write operations while the shared lock prevents concurrent
+ * read operations.
+ *
+ * External read access to iterators is synchronized by the caller holding an ObjectLock. This ensures no concurrent
+ * write operations as these require the ObjectLock but still allows concurrent reads as m_DataMutex is not locked.
+ *
  * @ingroup base
  */
 class Namespace final : public Object
@@ -51,23 +61,19 @@ class Namespace final : public Object
 public:
 	DECLARE_OBJECT(Namespace);
 
-	typedef std::map<String, NamespaceValue::Ptr>::iterator Iterator;
+	typedef std::map<String, NamespaceValue>::iterator Iterator;
 
-	typedef std::map<String, NamespaceValue::Ptr>::value_type Pair;
+	typedef std::map<String, NamespaceValue>::value_type Pair;
 
 	explicit Namespace(bool constValues = false);
 
 	Value Get(const String& field) const;
 	bool Get(const String& field, Value *value) const;
-	void Set(const String& field, const Value& value, bool overrideFrozen = false);
+	void Set(const String& field, const Value& value, bool isConst = false, const DebugInfo& debugInfo = DebugInfo());
 	bool Contains(const String& field) const;
-	void Remove(const String& field, bool overrideFrozen = false);
+	void Remove(const String& field);
 	void Freeze();
 
-	NamespaceValue::Ptr GetAttribute(const String& field) const;
-	void SetAttribute(const String& field, const NamespaceValue::Ptr& nsVal);
-	void RemoveAttribute(const String& field);
-
 	Iterator Begin();
 	Iterator End();
 
@@ -81,9 +87,12 @@ class Namespace final : public Object
 	static Object::Ptr GetPrototype();
 
 private:
-	std::map<String, NamespaceValue::Ptr> m_Data;
+	std::shared_lock<std::shared_timed_mutex> ReadLockUnlessFrozen() const;
+
+	std::map<String, NamespaceValue> m_Data;
+	mutable std::shared_timed_mutex m_DataMutex;
 	bool m_ConstValues;
-	bool m_Frozen;
+	std::atomic<bool> m_Frozen;
 };
 
 Namespace::Iterator begin(const Namespace::Ptr& x);
diff --git a/lib/base/scriptframe.cpp b/lib/base/scriptframe.cpp
index 4454d7733fb..b9725cf60e6 100644
--- a/lib/base/scriptframe.cpp
+++ b/lib/base/scriptframe.cpp
@@ -5,12 +5,13 @@
 #include "base/namespace.hpp"
 #include "base/exception.hpp"
 #include "base/configuration.hpp"
+#include "base/utility.hpp"
 
 using namespace icinga;
 
 boost::thread_specific_ptr<std::stack<ScriptFrame *> > ScriptFrame::m_ScriptFrames;
 
-static Namespace::Ptr l_InternalNS;
+static Namespace::Ptr l_SystemNS, l_TypesNS, l_StatsNS, l_InternalNS;
 
 /* Ensure that this gets called with highest priority
  * and wins against other static initializers in lib/icinga, etc.
@@ -19,27 +20,35 @@ static Namespace::Ptr l_InternalNS;
 INITIALIZE_ONCE_WITH_PRIORITY([]() {
 	Namespace::Ptr globalNS = ScriptGlobal::GetGlobals();
 
-	Namespace::Ptr systemNS = new Namespace(true);
-	systemNS->Freeze();
-	globalNS->SetAttribute("System", new ConstEmbeddedNamespaceValue(systemNS));
+	l_SystemNS = new Namespace(true);
+	l_SystemNS->Set("PlatformKernel", Utility::GetPlatformKernel());
+	l_SystemNS->Set("PlatformKernelVersion", Utility::GetPlatformKernelVersion());
+	l_SystemNS->Set("PlatformName", Utility::GetPlatformName());
+	l_SystemNS->Set("PlatformVersion", Utility::GetPlatformVersion());
+	l_SystemNS->Set("PlatformArchitecture", Utility::GetPlatformArchitecture());
+	l_SystemNS->Set("BuildHostName", ICINGA_BUILD_HOST_NAME);
+	l_SystemNS->Set("BuildCompilerName", ICINGA_BUILD_COMPILER_NAME);
+	l_SystemNS->Set("BuildCompilerVersion", ICINGA_BUILD_COMPILER_VERSION);
+	globalNS->Set("System", l_SystemNS, true);
 
-	systemNS->SetAttribute("Configuration", new EmbeddedNamespaceValue(new Configuration()));
+	l_SystemNS->Set("Configuration", new Configuration());
 
-	Namespace::Ptr typesNS = new Namespace(true);
-	typesNS->Freeze();
-	globalNS->SetAttribute("Types", new ConstEmbeddedNamespaceValue(typesNS));
+	l_TypesNS = new Namespace(true);
+	globalNS->Set("Types", l_TypesNS, true);
 
-	Namespace::Ptr statsNS = new Namespace(true);
-	statsNS->Freeze();
-	globalNS->SetAttribute("StatsFunctions", new ConstEmbeddedNamespaceValue(statsNS));
+	l_StatsNS = new Namespace(true);
+	globalNS->Set("StatsFunctions", l_StatsNS, true);
 
 	l_InternalNS = new Namespace(true);
-	globalNS->SetAttribute("Internal", new ConstEmbeddedNamespaceValue(l_InternalNS));
+	globalNS->Set("Internal", l_InternalNS, true);
 }, InitializePriority::CreateNamespaces);
 
-INITIALIZE_ONCE([]() {
+INITIALIZE_ONCE_WITH_PRIORITY([]() {
+	l_SystemNS->Freeze();
+	l_TypesNS->Freeze();
+	l_StatsNS->Freeze();
 	l_InternalNS->Freeze();
-});
+}, InitializePriority::FreezeNamespaces);
 
 ScriptFrame::ScriptFrame(bool allocLocals)
 	: Locals(allocLocals ? new Dictionary() : nullptr), Self(ScriptGlobal::GetGlobals()), Sandboxed(false), Depth(0)
diff --git a/lib/base/scriptglobal.cpp b/lib/base/scriptglobal.cpp
index 545c097066f..f730612b1d7 100644
--- a/lib/base/scriptglobal.cpp
+++ b/lib/base/scriptglobal.cpp
@@ -65,7 +65,7 @@ void ScriptGlobal::Set(const String& name, const Value& value, bool overrideFroz
 
 void ScriptGlobal::SetConst(const String& name, const Value& value)
 {
-	GetGlobals()->SetAttribute(name, new ConstEmbeddedNamespaceValue(value));
+	GetGlobals()->Set(name, value, true);
 }
 
 bool ScriptGlobal::Exists(const String& name)
@@ -93,7 +93,7 @@ void ScriptGlobal::WriteToFile(const String& filename)
 
 	ObjectLock olock(m_Globals);
 	for (const Namespace::Pair& kv : m_Globals) {
-		Value value = kv.second->Get();
+		Value value = kv.second.Val;
 
 		if (value.IsObject())
 			value = Convert::ToString(value);
diff --git a/lib/base/scriptutils.cpp b/lib/base/scriptutils.cpp
index b24cdbd4a4e..7fe856de355 100644
--- a/lib/base/scriptutils.cpp
+++ b/lib/base/scriptutils.cpp
@@ -71,11 +71,11 @@ enum MatchType
 
 void ScriptUtils::StaticInitialize()
 {
-	ScriptGlobal::Set("System.MatchAll", MatchAll, true);
-	ScriptGlobal::Set("System.MatchAny", MatchAny, true);
+	ScriptGlobal::Set("System.MatchAll", MatchAll);
+	ScriptGlobal::Set("System.MatchAny", MatchAny);
 
-	ScriptGlobal::Set("System.GlobFile", GlobFile, true);
-	ScriptGlobal::Set("System.GlobDirectory", GlobDirectory, true);
+	ScriptGlobal::Set("System.GlobFile", GlobFile);
+	ScriptGlobal::Set("System.GlobDirectory", GlobDirectory);
 }
 
 String ScriptUtils::CastString(const Value& value)
diff --git a/lib/base/serializer.cpp b/lib/base/serializer.cpp
index c3bd84ad137..b8b140a3a6c 100644
--- a/lib/base/serializer.cpp
+++ b/lib/base/serializer.cpp
@@ -131,7 +131,7 @@ static Dictionary::Ptr SerializeNamespace(const Namespace::Ptr& input, int attri
 	ObjectLock olock(input);
 
 	for (const Namespace::Pair& kv : input) {
-		Value val = kv.second->Get();
+		Value val = kv.second.Val;
 		stack.Push(kv.first, val);
 
 		auto serialized (SerializeInternal(val, attributeTypes, stack, dryRun));
diff --git a/lib/base/sysloglogger.cpp b/lib/base/sysloglogger.cpp
index 21d6f6d6aa5..fc2ec095199 100644
--- a/lib/base/sysloglogger.cpp
+++ b/lib/base/sysloglogger.cpp
@@ -19,26 +19,26 @@ std::map<String, int> SyslogHelper::m_FacilityMap;
 
 void SyslogHelper::StaticInitialize()
 {
-	ScriptGlobal::Set("System.FacilityAuth", "LOG_AUTH", true);
-	ScriptGlobal::Set("System.FacilityAuthPriv", "LOG_AUTHPRIV", true);
-	ScriptGlobal::Set("System.FacilityCron", "LOG_CRON", true);
-	ScriptGlobal::Set("System.FacilityDaemon", "LOG_DAEMON", true);
-	ScriptGlobal::Set("System.FacilityFtp", "LOG_FTP", true);
-	ScriptGlobal::Set("System.FacilityKern", "LOG_KERN", true);
-	ScriptGlobal::Set("System.FacilityLocal0", "LOG_LOCAL0", true);
-	ScriptGlobal::Set("System.FacilityLocal1", "LOG_LOCAL1", true);
-	ScriptGlobal::Set("System.FacilityLocal2", "LOG_LOCAL2", true);
-	ScriptGlobal::Set("System.FacilityLocal3", "LOG_LOCAL3", true);
-	ScriptGlobal::Set("System.FacilityLocal4", "LOG_LOCAL4", true);
-	ScriptGlobal::Set("System.FacilityLocal5", "LOG_LOCAL5", true);
-	ScriptGlobal::Set("System.FacilityLocal6", "LOG_LOCAL6", true);
-	ScriptGlobal::Set("System.FacilityLocal7", "LOG_LOCAL7", true);
-	ScriptGlobal::Set("System.FacilityLpr", "LOG_LPR", true);
-	ScriptGlobal::Set("System.FacilityMail", "LOG_MAIL", true);
-	ScriptGlobal::Set("System.FacilityNews", "LOG_NEWS", true);
-	ScriptGlobal::Set("System.FacilitySyslog", "LOG_SYSLOG", true);
-	ScriptGlobal::Set("System.FacilityUser", "LOG_USER", true);
-	ScriptGlobal::Set("System.FacilityUucp", "LOG_UUCP", true);
+	ScriptGlobal::Set("System.FacilityAuth", "LOG_AUTH");
+	ScriptGlobal::Set("System.FacilityAuthPriv", "LOG_AUTHPRIV");
+	ScriptGlobal::Set("System.FacilityCron", "LOG_CRON");
+	ScriptGlobal::Set("System.FacilityDaemon", "LOG_DAEMON");
+	ScriptGlobal::Set("System.FacilityFtp", "LOG_FTP");
+	ScriptGlobal::Set("System.FacilityKern", "LOG_KERN");
+	ScriptGlobal::Set("System.FacilityLocal0", "LOG_LOCAL0");
+	ScriptGlobal::Set("System.FacilityLocal1", "LOG_LOCAL1");
+	ScriptGlobal::Set("System.FacilityLocal2", "LOG_LOCAL2");
+	ScriptGlobal::Set("System.FacilityLocal3", "LOG_LOCAL3");
+	ScriptGlobal::Set("System.FacilityLocal4", "LOG_LOCAL4");
+	ScriptGlobal::Set("System.FacilityLocal5", "LOG_LOCAL5");
+	ScriptGlobal::Set("System.FacilityLocal6", "LOG_LOCAL6");
+	ScriptGlobal::Set("System.FacilityLocal7", "LOG_LOCAL7");
+	ScriptGlobal::Set("System.FacilityLpr", "LOG_LPR");
+	ScriptGlobal::Set("System.FacilityMail", "LOG_MAIL");
+	ScriptGlobal::Set("System.FacilityNews", "LOG_NEWS");
+	ScriptGlobal::Set("System.FacilitySyslog", "LOG_SYSLOG");
+	ScriptGlobal::Set("System.FacilityUser", "LOG_USER");
+	ScriptGlobal::Set("System.FacilityUucp", "LOG_UUCP");
 
 	m_FacilityMap["LOG_AUTH"] = LOG_AUTH;
 	m_FacilityMap["LOG_AUTHPRIV"] = LOG_AUTHPRIV;
diff --git a/lib/base/type.cpp b/lib/base/type.cpp
index 604a07ae5b0..64a442d980c 100644
--- a/lib/base/type.cpp
+++ b/lib/base/type.cpp
@@ -24,7 +24,7 @@ String Type::ToString() const
 
 void Type::Register(const Type::Ptr& type)
 {
-	ScriptGlobal::Set("Types." + type->GetName(), type, true);
+	ScriptGlobal::Set("Types." + type->GetName(), type);
 }
 
 Type::Ptr Type::GetByName(const String& name)
@@ -54,7 +54,7 @@ std::vector<Type::Ptr> Type::GetAllTypes()
 		ObjectLock olock(typesNS);
 
 		for (const Namespace::Pair& kv : typesNS) {
-			Value value = kv.second->Get();
+			Value value = kv.second.Val;
 
 			if (value.IsObjectType<Type>())
 				types.push_back(value);
diff --git a/lib/config/expression.cpp b/lib/config/expression.cpp
index ba7ff6c3f48..a8e99861a1f 100644
--- a/lib/config/expression.cpp
+++ b/lib/config/expression.cpp
@@ -675,20 +675,11 @@ ExpressionResult SetConstExpression::DoEvaluate(ScriptFrame& frame, DebugHint *d
 {
 	auto globals = ScriptGlobal::GetGlobals();
 
-	auto attr = globals->GetAttribute(m_Name);
-
-	if (dynamic_pointer_cast<ConstEmbeddedNamespaceValue>(attr)) {
-		std::ostringstream msgbuf;
-		msgbuf << "Value for constant '" << m_Name << "' was modified. This behaviour is deprecated.\n";
-		ShowCodeLocation(msgbuf, GetDebugInfo(), false);
-		Log(LogWarning, msgbuf.str());
-	}
-
 	ExpressionResult operandres = m_Operand->Evaluate(frame);
 	CHECK_RESULT(operandres);
 	Value operand = operandres.GetValue();
 
-	globals->SetAttribute(m_Name, new ConstEmbeddedNamespaceValue(operand));
+	globals->Set(m_Name, operand, true);
 
 	return Empty;
 }
diff --git a/lib/db_ido/dbquery.cpp b/lib/db_ido/dbquery.cpp
index 01196a53705..1de2928431e 100644
--- a/lib/db_ido/dbquery.cpp
+++ b/lib/db_ido/dbquery.cpp
@@ -12,22 +12,22 @@ std::map<String, int> DbQuery::m_CategoryFilterMap;
 
 void DbQuery::StaticInitialize()
 {
-	ScriptGlobal::Set("Icinga.DbCatConfig", DbCatConfig, true);
-	ScriptGlobal::Set("Icinga.DbCatState", DbCatState, true);
-	ScriptGlobal::Set("Icinga.DbCatAcknowledgement", DbCatAcknowledgement, true);
-	ScriptGlobal::Set("Icinga.DbCatComment", DbCatComment, true);
-	ScriptGlobal::Set("Icinga.DbCatDowntime", DbCatDowntime, true);
-	ScriptGlobal::Set("Icinga.DbCatEventHandler", DbCatEventHandler, true);
-	ScriptGlobal::Set("Icinga.DbCatExternalCommand", DbCatExternalCommand, true);
-	ScriptGlobal::Set("Icinga.DbCatFlapping", DbCatFlapping, true);
-	ScriptGlobal::Set("Icinga.DbCatCheck", DbCatCheck, true);
-	ScriptGlobal::Set("Icinga.DbCatLog", DbCatLog, true);
-	ScriptGlobal::Set("Icinga.DbCatNotification", DbCatNotification, true);
-	ScriptGlobal::Set("Icinga.DbCatProgramStatus", DbCatProgramStatus, true);
-	ScriptGlobal::Set("Icinga.DbCatRetention", DbCatRetention, true);
-	ScriptGlobal::Set("Icinga.DbCatStateHistory", DbCatStateHistory, true);
-
-	ScriptGlobal::Set("Icinga.DbCatEverything", DbCatEverything, true);
+	ScriptGlobal::Set("Icinga.DbCatConfig", DbCatConfig);
+	ScriptGlobal::Set("Icinga.DbCatState", DbCatState);
+	ScriptGlobal::Set("Icinga.DbCatAcknowledgement", DbCatAcknowledgement);
+	ScriptGlobal::Set("Icinga.DbCatComment", DbCatComment);
+	ScriptGlobal::Set("Icinga.DbCatDowntime", DbCatDowntime);
+	ScriptGlobal::Set("Icinga.DbCatEventHandler", DbCatEventHandler);
+	ScriptGlobal::Set("Icinga.DbCatExternalCommand", DbCatExternalCommand);
+	ScriptGlobal::Set("Icinga.DbCatFlapping", DbCatFlapping);
+	ScriptGlobal::Set("Icinga.DbCatCheck", DbCatCheck);
+	ScriptGlobal::Set("Icinga.DbCatLog", DbCatLog);
+	ScriptGlobal::Set("Icinga.DbCatNotification", DbCatNotification);
+	ScriptGlobal::Set("Icinga.DbCatProgramStatus", DbCatProgramStatus);
+	ScriptGlobal::Set("Icinga.DbCatRetention", DbCatRetention);
+	ScriptGlobal::Set("Icinga.DbCatStateHistory", DbCatStateHistory);
+
+	ScriptGlobal::Set("Icinga.DbCatEverything", DbCatEverything);
 
 	m_CategoryFilterMap["DbCatConfig"] = DbCatConfig;
 	m_CategoryFilterMap["DbCatState"] = DbCatState;
diff --git a/lib/icinga/checkresult.cpp b/lib/icinga/checkresult.cpp
index cb445af6c6d..07f7219c444 100644
--- a/lib/icinga/checkresult.cpp
+++ b/lib/icinga/checkresult.cpp
@@ -9,13 +9,13 @@ using namespace icinga;
 REGISTER_TYPE(CheckResult);
 
 INITIALIZE_ONCE([]() {
-	ScriptGlobal::Set("Icinga.ServiceOK", ServiceOK, true);
-	ScriptGlobal::Set("Icinga.ServiceWarning", ServiceWarning, true);
-	ScriptGlobal::Set("Icinga.ServiceCritical", ServiceCritical, true);
-	ScriptGlobal::Set("Icinga.ServiceUnknown", ServiceUnknown, true);
+	ScriptGlobal::Set("Icinga.ServiceOK", ServiceOK);
+	ScriptGlobal::Set("Icinga.ServiceWarning", ServiceWarning);
+	ScriptGlobal::Set("Icinga.ServiceCritical", ServiceCritical);
+	ScriptGlobal::Set("Icinga.ServiceUnknown", ServiceUnknown);
 
-	ScriptGlobal::Set("Icinga.HostUp", HostUp, true);
-	ScriptGlobal::Set("Icinga.HostDown", HostDown, true);
+	ScriptGlobal::Set("Icinga.HostUp", HostUp);
+	ScriptGlobal::Set("Icinga.HostDown", HostDown);
 })
 
 double CheckResult::CalculateExecutionTime() const
diff --git a/lib/icinga/cib.cpp b/lib/icinga/cib.cpp
index 898b0e75fbe..ce71a59924a 100644
--- a/lib/icinga/cib.cpp
+++ b/lib/icinga/cib.cpp
@@ -269,7 +269,7 @@ std::pair<Dictionary::Ptr, Array::Ptr> CIB::GetFeatureStats()
 		ObjectLock olock(statsFunctions);
 
 		for (const Namespace::Pair& kv : statsFunctions)
-			static_cast<Function::Ptr>(kv.second->Get())->Invoke({ status, perfdata });
+			static_cast<Function::Ptr>(kv.second.Val)->Invoke({ status, perfdata });
 	}
 
 	return std::make_pair(status, perfdata);
diff --git a/lib/icinga/downtime.cpp b/lib/icinga/downtime.cpp
index e67df423ba2..cd8568590e5 100644
--- a/lib/icinga/downtime.cpp
+++ b/lib/icinga/downtime.cpp
@@ -31,9 +31,9 @@ INITIALIZE_ONCE(&Downtime::StaticInitialize);
 
 void Downtime::StaticInitialize()
 {
-	ScriptGlobal::Set("Icinga.DowntimeNoChildren", "DowntimeNoChildren", true);
-	ScriptGlobal::Set("Icinga.DowntimeTriggeredChildren", "DowntimeTriggeredChildren", true);
-	ScriptGlobal::Set("Icinga.DowntimeNonTriggeredChildren", "DowntimeNonTriggeredChildren", true);
+	ScriptGlobal::Set("Icinga.DowntimeNoChildren", "DowntimeNoChildren");
+	ScriptGlobal::Set("Icinga.DowntimeTriggeredChildren", "DowntimeTriggeredChildren");
+	ScriptGlobal::Set("Icinga.DowntimeNonTriggeredChildren", "DowntimeNonTriggeredChildren");
 }
 
 String DowntimeNameComposer::MakeName(const String& shortName, const Object::Ptr& context) const
diff --git a/lib/icinga/icingaapplication.cpp b/lib/icinga/icingaapplication.cpp
index 7e0312754e2..c20ee4cfb13 100644
--- a/lib/icinga/icingaapplication.cpp
+++ b/lib/icinga/icingaapplication.cpp
@@ -28,6 +28,8 @@ REGISTER_TYPE(IcingaApplication);
 /* Ensure that the priority is lower than the basic System namespace initialization in scriptframe.cpp. */
 INITIALIZE_ONCE_WITH_PRIORITY(&IcingaApplication::StaticInitialize, InitializePriority::InitIcingaApplication);
 
+static Namespace::Ptr l_IcingaNS;
+
 void IcingaApplication::StaticInitialize()
 {
 	/* Pre-fill global constants, can be overridden with user input later in icinga-app/icinga.cpp. */
@@ -58,11 +60,14 @@ void IcingaApplication::StaticInitialize()
 	Namespace::Ptr globalNS = ScriptGlobal::GetGlobals();
 	VERIFY(globalNS);
 
-	Namespace::Ptr icingaNS = new Namespace(true);
-	icingaNS->Freeze();
-	globalNS->SetAttribute("Icinga", new ConstEmbeddedNamespaceValue(icingaNS));
+	l_IcingaNS = new Namespace(true);
+	globalNS->Set("Icinga", l_IcingaNS, true);
 }
 
+INITIALIZE_ONCE_WITH_PRIORITY([]() {
+	l_IcingaNS->Freeze();
+}, InitializePriority::FreezeNamespaces);
+
 REGISTER_STATSFUNCTION(IcingaApplication, &IcingaApplication::StatsFunc);
 
 void IcingaApplication::StatsFunc(const Dictionary::Ptr& status, const Array::Ptr& perfdata)
diff --git a/lib/icinga/notification.cpp b/lib/icinga/notification.cpp
index f3826ca8140..fb7bc1c7094 100644
--- a/lib/icinga/notification.cpp
+++ b/lib/icinga/notification.cpp
@@ -63,22 +63,22 @@ Dictionary::Ptr NotificationNameComposer::ParseName(const String& name) const
 
 void Notification::StaticInitialize()
 {
-	ScriptGlobal::Set("Icinga.OK", "OK", true);
-	ScriptGlobal::Set("Icinga.Warning", "Warning", true);
-	ScriptGlobal::Set("Icinga.Critical", "Critical", true);
-	ScriptGlobal::Set("Icinga.Unknown", "Unknown", true);
-	ScriptGlobal::Set("Icinga.Up", "Up", true);
-	ScriptGlobal::Set("Icinga.Down", "Down", true);
-
-	ScriptGlobal::Set("Icinga.DowntimeStart", "DowntimeStart", true);
-	ScriptGlobal::Set("Icinga.DowntimeEnd", "DowntimeEnd", true);
-	ScriptGlobal::Set("Icinga.DowntimeRemoved", "DowntimeRemoved", true);
-	ScriptGlobal::Set("Icinga.Custom", "Custom", true);
-	ScriptGlobal::Set("Icinga.Acknowledgement", "Acknowledgement", true);
-	ScriptGlobal::Set("Icinga.Problem", "Problem", true);
-	ScriptGlobal::Set("Icinga.Recovery", "Recovery", true);
-	ScriptGlobal::Set("Icinga.FlappingStart", "FlappingStart", true);
-	ScriptGlobal::Set("Icinga.FlappingEnd", "FlappingEnd", true);
+	ScriptGlobal::Set("Icinga.OK", "OK");
+	ScriptGlobal::Set("Icinga.Warning", "Warning");
+	ScriptGlobal::Set("Icinga.Critical", "Critical");
+	ScriptGlobal::Set("Icinga.Unknown", "Unknown");
+	ScriptGlobal::Set("Icinga.Up", "Up");
+	ScriptGlobal::Set("Icinga.Down", "Down");
+
+	ScriptGlobal::Set("Icinga.DowntimeStart", "DowntimeStart");
+	ScriptGlobal::Set("Icinga.DowntimeEnd", "DowntimeEnd");
+	ScriptGlobal::Set("Icinga.DowntimeRemoved", "DowntimeRemoved");
+	ScriptGlobal::Set("Icinga.Custom", "Custom");
+	ScriptGlobal::Set("Icinga.Acknowledgement", "Acknowledgement");
+	ScriptGlobal::Set("Icinga.Problem", "Problem");
+	ScriptGlobal::Set("Icinga.Recovery", "Recovery");
+	ScriptGlobal::Set("Icinga.FlappingStart", "FlappingStart");
+	ScriptGlobal::Set("Icinga.FlappingEnd", "FlappingEnd");
 
 	m_StateFilterMap["OK"] = StateFilterOK;
 	m_StateFilterMap["Warning"] = StateFilterWarning;
diff --git a/lib/icingadb/icingadb-stats.cpp b/lib/icingadb/icingadb-stats.cpp
index 375d0f7cad8..476756b5a2e 100644
--- a/lib/icingadb/icingadb-stats.cpp
+++ b/lib/icingadb/icingadb-stats.cpp
@@ -24,7 +24,7 @@ Dictionary::Ptr IcingaDB::GetStats()
 
 	for (auto& kv : statsFunctions)
 	{
-		Function::Ptr func = kv.second->Get();
+		Function::Ptr func = kv.second.Val;
 
 		if (!func)
 			BOOST_THROW_EXCEPTION(std::invalid_argument("Invalid status function name."));
diff --git a/lib/remote/variablequeryhandler.cpp b/lib/remote/variablequeryhandler.cpp
index aef896e6fbb..d732d3085ce 100644
--- a/lib/remote/variablequeryhandler.cpp
+++ b/lib/remote/variablequeryhandler.cpp
@@ -35,7 +35,7 @@ class VariableTargetProvider final : public TargetProvider
 			Namespace::Ptr globals = ScriptGlobal::GetGlobals();
 			ObjectLock olock(globals);
 			for (const Namespace::Pair& kv : globals) {
-				addTarget(GetTargetForVar(kv.first, kv.second->Get()));
+				addTarget(GetTargetForVar(kv.first, kv.second.Val));
 			}
 		}
 	}