diff --git a/src/ll/api/command/CommandHandle.cpp b/src/ll/api/command/CommandHandle.cpp
index d0773efa16..89edd0d9a2 100644
--- a/src/ll/api/command/CommandHandle.cpp
+++ b/src/ll/api/command/CommandHandle.cpp
@@ -14,9 +14,9 @@ struct CommandHandle::Impl {
     gsl::not_null<CommandRegistrar*>           registrar;
     gsl::not_null<CommandRegistry::Signature*> signature;
     bool                                       owned;
+    std::recursive_mutex                       mutex;
 };
 
-
 CommandHandle::CommandHandle(CommandRegistrar& registrar, CommandRegistry::Signature* signature, bool owned)
 : impl(std::make_unique<Impl>(&registrar, signature, owned)) {}
 
@@ -26,8 +26,9 @@ CommandHandle::~CommandHandle() = default;
 CommandRegistrar& CommandHandle::getRegistrar() { return *impl->registrar; }
 
 void CommandHandle::registerOverload(OverloadData&& data) {
-    auto& overload  = impl->signature->overloads.emplace_back(CommandVersion{}, data.getFactory());
-    overload.params = data.moveParams();
+    std::lock_guard lock{impl->mutex};
+    auto&           overload = impl->signature->overloads.emplace_back(CommandVersion{}, data.getFactory());
+    overload.params          = data.moveParams();
     impl->registrar->getRegistry().registerOverloadInternal(*impl->signature, overload);
 }
 char const* CommandHandle::addText(std::string_view text) { return impl->registrar->addText(*this, text); }
diff --git a/src/ll/api/command/CommandRegistrar.cpp b/src/ll/api/command/CommandRegistrar.cpp
index 6cba79a649..ec1d7e4d47 100644
--- a/src/ll/api/command/CommandRegistrar.cpp
+++ b/src/ll/api/command/CommandRegistrar.cpp
@@ -21,6 +21,7 @@ namespace ll::command {
 struct CommandRegistrar::Impl {
     std::unordered_map<std::string, CommandHandle> commands;
     std::unordered_map<std::string, uint64>        textWithRef;
+    std::recursive_mutex                           mutex;
 };
 
 CommandRegistrar::CommandRegistrar() : impl(std::make_unique<Impl>()) {}
@@ -38,11 +39,15 @@ CommandHandle& CommandRegistrar::getOrCreateCommand(
     CommandFlag            flag,
     std::weak_ptr<plugin::Plugin> /*plugin*/
 ) {
-    auto& registry  = getRegistry();
-    auto  signature = registry.findCommand(name);
+    std::lock_guard lock{impl->mutex};
+    auto&           registry  = getRegistry();
+    auto            signature = registry.findCommand(name);
     if (!signature) {
         registry.registerCommand(name, description.c_str(), requirement, flag);
         signature = registry.findCommand(name);
+        if (!signature) {
+            throw std::runtime_error{"failed to register command " + name};
+        }
         return impl->commands.try_emplace(name, *this, signature, true).first->second;
     } else if (impl->commands.contains(signature->name)) {
         return impl->commands.at(signature->name);
@@ -124,7 +129,8 @@ bool CommandRegistrar::setSoftEnumValues(std::string const& name, std::vector<st
 }
 
 char const* CommandRegistrar::addText(CommandHandle& /*handle*/, std::string_view text) {
-    std::string storedName{"ll_text_enum_name_"};
+    std::lock_guard lock{impl->mutex};
+    std::string     storedName{"ll_text_enum_name_"};
     storedName += text;
     if (impl->textWithRef.contains(storedName)) {
         impl->textWithRef.at(storedName)++;
diff --git a/src/ll/api/command/OverloadData.cpp b/src/ll/api/command/OverloadData.cpp
index 1e2c2b1e12..e620cc65c6 100644
--- a/src/ll/api/command/OverloadData.cpp
+++ b/src/ll/api/command/OverloadData.cpp
@@ -22,16 +22,24 @@ struct OverloadData::Impl {
     gsl::not_null<CommandHandle*>     handle;
     CommandRegistry::FactoryFn        factory{};
     std::vector<CommandParameterData> params;
+    std::recursive_mutex              mutex;
 };
 
 OverloadData::OverloadData(CommandHandle& handle) : impl(std::make_unique<Impl>(&handle)) {}
 
 OverloadData::~OverloadData() = default;
 
-CommandRegistry::FactoryFn        OverloadData::getFactory() { return impl->factory; }
-std::vector<CommandParameterData> OverloadData::moveParams() { return std::move(impl->params); }
+CommandRegistry::FactoryFn OverloadData::getFactory() {
+    std::lock_guard lock{impl->mutex};
+    return impl->factory;
+}
+std::vector<CommandParameterData> OverloadData::moveParams() {
+    std::lock_guard lock{impl->mutex};
+    return std::move(impl->params);
+}
 
 CommandParameterData& OverloadData::back() {
+    std::lock_guard lock{impl->mutex};
     if (!impl->params.empty()) {
         return impl->params.back();
     } else {
@@ -49,7 +57,8 @@ CommandParameterData& OverloadData::addParamImpl(
     int                                flagOffset,
     bool                               optional
 ) {
-    auto& param =
+    std::lock_guard lock{impl->mutex};
+    auto&           param =
         impl->params.emplace_back(id, parser, std::string{name}, type, enumNameOrPostfix, offset, optional, flagOffset);
     if (id == Bedrock::type_id<CommandRegistry, CommandBlockName>()
         || id == Bedrock::type_id<CommandRegistry, CommandItem>()) {
@@ -61,6 +70,7 @@ CommandParameterData& OverloadData::addParamImpl(
     return param;
 }
 CommandParameterData& OverloadData::addTextImpl(std::string_view text, int offset) {
+    std::lock_guard lock{impl->mutex};
     return addParamImpl(
         Bedrock::type_id<CommandRegistry, Placeholder>(),
         &CommandRegistry::parse<Placeholder>,
@@ -74,6 +84,7 @@ CommandParameterData& OverloadData::addTextImpl(std::string_view text, int offse
 }
 
 void OverloadData::setFactory(CommandRegistry::FactoryFn fn) {
+    std::lock_guard lock{impl->mutex};
     impl->factory = fn;
     impl->handle->registerOverload(std::move(*this));
 }
diff --git a/src/ll/core/dimension/CustomDimensionConfig.cpp b/src/ll/core/dimension/CustomDimensionConfig.cpp
index a823245c65..ec92c48731 100644
--- a/src/ll/core/dimension/CustomDimensionConfig.cpp
+++ b/src/ll/core/dimension/CustomDimensionConfig.cpp
@@ -19,7 +19,7 @@ void setDimensionConfigPath() {
     if (!ll::service::getLevel()) {
         throw std::runtime_error("Level nullptr");
     }
-    dimensionConfigPath /= string_utils::str2u8str(ll::service::getLevel()->getLevelName());
+    dimensionConfigPath /= string_utils::str2u8str(ll::service::getLevel()->getLevelData().getLevelName());
     dimensionConfigPath /= u8"dimension_config.json";
 }
 
diff --git a/src/mc/world/actor/Mob.cpp b/src/mc/world/actor/Mob.cpp
new file mode 100644
index 0000000000..136b184b72
--- /dev/null
+++ b/src/mc/world/actor/Mob.cpp
@@ -0,0 +1,6 @@
+#include "mc/world/actor/Mob.h"
+
+void Mob::refreshInventory() {
+    sendInventory(true);
+    sendArmor(std::bitset<4>{"1111"});
+}
diff --git a/src/mc/world/actor/Mob.h b/src/mc/world/actor/Mob.h
index 82e4a823d8..1c23e6643c 100644
--- a/src/mc/world/actor/Mob.h
+++ b/src/mc/world/actor/Mob.h
@@ -34,10 +34,7 @@ class BodyControl;
 
 class Mob : public ::Actor {
 public:
-    inline void refreshInventory() {
-        sendInventory(true);
-        sendArmor(std::bitset<4>{"1111"});
-    }
+    LLAPI void refreshInventory();
 
     // prevent constructor by default
     Mob& operator=(Mob const&);
diff --git a/src/mc/world/actor/player/Player.cpp b/src/mc/world/actor/player/Player.cpp
index 3f32cf909a..5e90fd1398 100644
--- a/src/mc/world/actor/player/Player.cpp
+++ b/src/mc/world/actor/player/Player.cpp
@@ -39,6 +39,18 @@ optional_ref<ConnectionRequest const> Player::getConnectionRequest() const {
     return ll::service::getServerNetworkHandler()->fetchConnectionRequest(getNetworkIdentifier());
 }
 
+NetworkIdentifier const& Player::getNetworkIdentifier() const { return getUserEntityIdentifier().mNetworkId; }
+
+optional_ref<Certificate const> Player::getCertificate() const { return getUserEntityIdentifier().mCertificate.get(); }
+
+SubClientId const& Player::getClientSubId() const { return getUserEntityIdentifier().mClientSubId; }
+
+mce::UUID const& Player::getUuid() const { return getUserEntityIdentifier().mClientUUID; }
+
+std::string Player::getIPAndPort() const { return getNetworkIdentifier().getIPAndPort(); }
+
+bool Player::isOperator() const { return getPlayerPermissionLevel() == PlayerPermissionLevel::Operator; }
+
 std::string Player::getLocaleName() const {
     if (auto request = getConnectionRequest()) {
         return request->mRawToken->mDataInfo["LanguageCode"].asString("");
diff --git a/src/mc/world/actor/player/Player.h b/src/mc/world/actor/player/Player.h
index 41bd388ede..4d96bd59e3 100644
--- a/src/mc/world/actor/player/Player.h
+++ b/src/mc/world/actor/player/Player.h
@@ -102,32 +102,30 @@ class Player : public ::Mob {
 
     LLNDAPI optional_ref<ConnectionRequest const> getConnectionRequest() const;
 
-    [[nodiscard]] NetworkIdentifier const& getNetworkIdentifier() const { return getUserEntityIdentifier().mNetworkId; }
+    LLNDAPI NetworkIdentifier const& getNetworkIdentifier() const;
 
-    [[nodiscard]] optional_ref<Certificate const> getCertificate() const {
-        return getUserEntityIdentifier().mCertificate.get();
-    }
+    LLNDAPI optional_ref<Certificate const> getCertificate() const;
 
-    [[nodiscard]] SubClientId const& getClientSubId() const { return getUserEntityIdentifier().mClientSubId; }
+    LLNDAPI SubClientId const& getClientSubId() const;
 
     /**
      * @brief Get the player's uuid
      * @return Player's uuid
      */
-    [[nodiscard]] mce::UUID const& getUuid() const { return getUserEntityIdentifier().mClientUUID; }
+    LLNDAPI mce::UUID const& getUuid() const;
 
     /**
      * @brief Get the player's IP and port
      * @return player's IP and port
      */
-    [[nodiscard]] std::string getIPAndPort() const { return getNetworkIdentifier().getIPAndPort(); }
+    LLNDAPI std::string getIPAndPort() const;
 
     /**
      * @brief Determine if a player is an administrator of the server
      * @return Returns true if the player is an administrator of the server; otherwise returns false
      * @warning Custom permissions are not considered administrators
      */
-    [[nodiscard]] bool isOperator() const { return getPlayerPermissionLevel() == PlayerPermissionLevel::Operator; }
+    LLNDAPI bool isOperator() const;
 
     /**
      * @brief Get the player's real in-game nickname
diff --git a/src/mc/world/events/ServerInstanceEventCoordinator.h b/src/mc/world/events/ServerInstanceEventCoordinator.h
index 6661e3936f..34c000b90d 100644
--- a/src/mc/world/events/ServerInstanceEventCoordinator.h
+++ b/src/mc/world/events/ServerInstanceEventCoordinator.h
@@ -7,6 +7,8 @@
 #include "mc/events/ServerInstanceGameplayEvent.h"
 #include "mc/world/events/EventRef.h"
 
+class ServerInstance;
+
 class ServerInstanceEventCoordinator {
 public:
     // prevent constructor by default
diff --git a/src/mc/world/level/Level.h b/src/mc/world/level/Level.h
index 915f9024da..321cf06ce4 100644
--- a/src/mc/world/level/Level.h
+++ b/src/mc/world/level/Level.h
@@ -51,8 +51,6 @@ class ServerLevel;
 
 class Level : public ILevel, public BlockSourceListener, public IWorldRegistriesProvider {
 public:
-    [[nodiscard]] std::string const& getLevelName() const { return getLevelData().getLevelName(); }
-
     [[nodiscard]] ServerLevel& asServer() { return *reinterpret_cast<ServerLevel*>(this); }
 
     // prevent constructor by default