diff --git a/source/core/CMakeLists.txt b/source/core/CMakeLists.txt
index 8c2964e..bbad6f4 100644
--- a/source/core/CMakeLists.txt
+++ b/source/core/CMakeLists.txt
@@ -97,6 +97,7 @@ SET (star_core_HEADERS
     StarRandomPoint.hpp
     StarRect.hpp
     StarRpcPromise.hpp
+    StarRpcThreadPromise.hpp
     StarSectorArray2D.hpp
     StarSecureRandom.hpp
     StarSet.hpp
diff --git a/source/core/StarRpcThreadPromise.hpp b/source/core/StarRpcThreadPromise.hpp
new file mode 100644
index 0000000..bae509c
--- /dev/null
+++ b/source/core/StarRpcThreadPromise.hpp
@@ -0,0 +1,164 @@
+#ifndef STAR_RPC_THREAD_PROMISE_HPP
+#define STAR_RPC_THREAD_PROMISE_HPP
+
+#include "StarEither.hpp"
+#include "StarString.hpp"
+#include "StarThread.hpp"
+
+// A thread-safe version of RpcPromise.
+// This is just a copy-paste with a Mutex tacked on. I don't like that, but it's 11 PM.
+
+namespace Star {
+
+STAR_EXCEPTION(RpcThreadPromiseException, StarException);
+
+template <typename Result, typename Error = String>
+class RpcThreadPromiseKeeper {
+public:
+  void fulfill(Result result);
+  void fail(Error error);
+
+private:
+  template <typename ResultT, typename ErrorT>
+  friend class RpcThreadPromise;
+
+  function<void(Result)> m_fulfill;
+  function<void(Error)> m_fail;
+};
+
+template <typename Result, typename Error = String>
+class RpcThreadPromise {
+public:
+  static pair<RpcThreadPromise, RpcThreadPromiseKeeper<Result, Error>> createPair();
+  static RpcThreadPromise createFulfilled(Result result);
+  static RpcThreadPromise createFailed(Error error);
+
+  // Has the respoonse either failed or succeeded?
+  bool finished() const;
+  // Has the response finished with success?
+  bool succeeded() const;
+  // Has the response finished with failure?
+  bool failed() const;
+
+  // Returns the result of the rpc call on success, nothing on failure or when
+  // not yet finished.
+  Maybe<Result> result() const;
+
+  // Returns the error of a failed rpc call.  Returns nothing if the call is
+  // successful or not yet finished.
+  Maybe<Error> error() const;
+
+private:
+  template <typename ResultT, typename ErrorT>
+  friend class RpcThreadPromise;
+
+  struct Value {
+    Mutex mutex;
+
+    Maybe<Result> result;
+    Maybe<Error> error;
+  };
+
+  RpcThreadPromise() = default;
+
+  function<Value*()> m_getValue;
+};
+
+template <typename Result, typename Error>
+void RpcThreadPromiseKeeper<Result, Error>::fulfill(Result result) {
+  m_fulfill(move(result));
+}
+
+template <typename Result, typename Error>
+void RpcThreadPromiseKeeper<Result, Error>::fail(Error error) {
+  m_fail(move(error));
+}
+
+template <typename Result, typename Error>
+pair<RpcThreadPromise<Result, Error>, RpcThreadPromiseKeeper<Result, Error>> RpcThreadPromise<Result, Error>::createPair() {
+  auto valuePtr = make_shared<Value>();
+
+  RpcThreadPromise promise;
+  promise.m_getValue = [valuePtr]() {
+    return valuePtr.get();
+  };
+
+  RpcThreadPromiseKeeper<Result, Error> keeper;
+  keeper.m_fulfill = [valuePtr](Result result) {
+    MutexLocker lock(valuePtr->mutex);
+    if (valuePtr->result || valuePtr->error)
+      throw RpcThreadPromiseException("fulfill called on already finished RpcThreadPromise");
+    valuePtr->result = move(result);
+  };
+  keeper.m_fail = [valuePtr](Error error) {
+    MutexLocker lock(valuePtr->mutex);
+    if (valuePtr->result || valuePtr->error)
+      throw RpcThreadPromiseException("fail called on already finished RpcThreadPromise");
+    valuePtr->error = move(error);
+  };
+
+  return {move(promise), move(keeper)};
+}
+
+template <typename Result, typename Error>
+RpcThreadPromise<Result, Error> RpcThreadPromise<Result, Error>::createFulfilled(Result result) {
+  auto valuePtr = make_shared<Value>();
+  valuePtr->result = move(result);
+
+  RpcThreadPromise<Result, Error> promise;
+  promise.m_getValue = [valuePtr]() {
+    return valuePtr.get();
+  };
+  return promise;
+}
+
+template <typename Result, typename Error>
+RpcThreadPromise<Result, Error> RpcThreadPromise<Result, Error>::createFailed(Error error) {
+  auto valuePtr = make_shared<Value>();
+  valuePtr->error = move(error);
+
+  RpcThreadPromise<Result, Error> promise;
+  promise.m_getValue = [valuePtr]() {
+    return valuePtr.get();
+  };
+  return promise;
+}
+
+template <typename Result, typename Error>
+bool RpcThreadPromise<Result, Error>::finished() const {
+  auto val = m_getValue();
+  MutexLocker lock(val->mutex);
+  return val->result || val->error;
+}
+
+template <typename Result, typename Error>
+bool RpcThreadPromise<Result, Error>::succeeded() const {
+  auto val = m_getValue();
+  MutexLocker lock(val->mutex);
+  return val->result.isValid();
+}
+
+template <typename Result, typename Error>
+bool RpcThreadPromise<Result, Error>::failed() const {
+  auto val = m_getValue();
+  MutexLocker lock(val->mutex);
+  return val->error.isValid();
+}
+
+template <typename Result, typename Error>
+Maybe<Result> RpcThreadPromise<Result, Error>::result() const {
+  auto val = m_getValue();
+  MutexLocker lock(val->mutex);
+  return val->result;
+}
+
+template <typename Result, typename Error>
+Maybe<Error> RpcThreadPromise<Result, Error>::error() const {
+  auto val = m_getValue();
+  MutexLocker lock(val->mutex);
+  return val->error;
+}
+
+}
+
+#endif
diff --git a/source/game/StarUniverseServer.cpp b/source/game/StarUniverseServer.cpp
index 7742d1e..dcf76e3 100644
--- a/source/game/StarUniverseServer.cpp
+++ b/source/game/StarUniverseServer.cpp
@@ -258,6 +258,13 @@ void UniverseServer::setPvp(ConnectionId clientId, bool pvp) {
   }
 }
 
+RpcThreadPromise<Json> UniverseServer::sendWorldMessage(WorldId const& worldId, String const& message, JsonArray const& args) {
+  auto pair = RpcThreadPromise<Json>::createPair();
+  RecursiveMutexLocker locker(m_mainLock);
+  m_pendingWorldMessages[worldId].push_back({ message, args, pair.second });
+  return pair.first;
+}
+
 void UniverseServer::clientWarpPlayer(ConnectionId clientId, WarpAction action, bool deploy) {
   RecursiveMutexLocker locker(m_mainLock);
   m_pendingPlayerWarps[clientId] = pair<WarpAction, bool>(move(action), move(deploy));
@@ -502,6 +509,7 @@ void UniverseServer::run() {
       sendClientContextUpdates();
       respondToCelestialRequests();
       clearBrokenWorlds();
+      handleWorldMessages();
       shutdownInactiveWorlds();
       doTriggeredStorage();
     } catch (std::exception const& e) {
@@ -1029,6 +1037,23 @@ void UniverseServer::clearBrokenWorlds() {
   }
 }
 
+void UniverseServer::handleWorldMessages() {
+  RecursiveMutexLocker locker(m_mainLock);
+  ReadLocker clientsLocker(m_clientsLock);
+
+  auto it = m_pendingWorldMessages.begin();
+  while (it != m_pendingWorldMessages.end()) {
+    auto& worldId = it->first;
+    if (auto worldPtr = triggerWorldCreation(worldId).value()) {
+      worldPtr->passMessages(move(it->second));
+      it = m_pendingWorldMessages.erase(it);
+    }
+    else
+      ++it;
+
+  }
+}
+
 void UniverseServer::shutdownInactiveWorlds() {
   RecursiveMutexLocker locker(m_mainLock);
   ReadLocker clientsLocker(m_clientsLock);
@@ -1040,7 +1065,7 @@ void UniverseServer::shutdownInactiveWorlds() {
         world->stop();
         Logger::error("UniverseServer: World {} has stopped due to an error", worldId);
         worldDiedWithError(world->worldId());
-      } else if (world->clients().empty()) {
+      } else if (world->noClients()) {
         bool anyPendingWarps = false;
         for (auto const& p : m_pendingPlayerWarps) {
           if (resolveWarpAction(p.second.first, p.first, p.second.second).world == world->worldId()) {
@@ -1048,7 +1073,8 @@ void UniverseServer::shutdownInactiveWorlds() {
             break;
           }
         }
-        if (!anyPendingWarps) {
+
+        if (!anyPendingWarps && world->shouldExpire()) {
           Logger::info("UniverseServer: Stopping idle world {}", worldId);
           world->stop();
         }
diff --git a/source/game/StarUniverseServer.hpp b/source/game/StarUniverseServer.hpp
index da6fc9c..33b0838 100644
--- a/source/game/StarUniverseServer.hpp
+++ b/source/game/StarUniverseServer.hpp
@@ -78,6 +78,8 @@ public:
   bool isPvp(ConnectionId clientId) const;
   void setPvp(ConnectionId clientId, bool pvp);
 
+  RpcThreadPromise<Json> sendWorldMessage(WorldId const& worldId, String const& message, JsonArray const& args = {});
+
   void clientWarpPlayer(ConnectionId clientId, WarpAction action, bool deploy = false);
   void clientFlyShip(ConnectionId clientId, Vec3I const& system, SystemLocation const& location);
   WorldId clientWorld(ConnectionId clientId) const;
@@ -127,6 +129,7 @@ private:
   void respondToCelestialRequests();
   void processChat();
   void clearBrokenWorlds();
+  void handleWorldMessages();
   void shutdownInactiveWorlds();
   void doTriggeredStorage();
 
@@ -242,6 +245,7 @@ private:
   List<pair<WorldId, UniverseFlagAction>> m_pendingFlagActions;
   HashMap<ConnectionId, List<pair<String, ChatSendMode>>> m_pendingChat;
   Maybe<WorkerPoolPromise<CelestialCoordinate>> m_nextRandomizedStarterWorld;
+  Map<WorldId, List<WorldServerThread::Message>> m_pendingWorldMessages;
 
   List<TimeoutBan> m_tempBans;
 };
diff --git a/source/game/StarWorldServer.cpp b/source/game/StarWorldServer.cpp
index 3c5fbfe..83e5cea 100644
--- a/source/game/StarWorldServer.cpp
+++ b/source/game/StarWorldServer.cpp
@@ -41,6 +41,7 @@ WorldServer::WorldServer(WorldTemplatePtr const& worldTemplate, IODevicePtr stor
   m_tileProtectionEnabled = true;
   m_universeSettings = make_shared<UniverseSettings>();
   m_worldId = worldTemplate->worldName();
+  m_expiryTimer = GameTimer(0.0f);
 
   init(true);
   writeMetadata();
@@ -514,6 +515,10 @@ List<PacketPtr> WorldServer::getOutgoingPackets(ConnectionId clientId) {
   return move(clientInfo->outgoingPackets);
 }
 
+Maybe<Json> WorldServer::receiveMessage(ConnectionId fromConnection, String const& message, JsonArray const& args) {
+  return "what a wonderful world";
+}
+
 WorldServerFidelity WorldServer::fidelity() const {
   return m_fidelity;
 }
@@ -523,6 +528,19 @@ void WorldServer::setFidelity(WorldServerFidelity fidelity) {
   m_fidelityConfig = m_serverConfig.get("fidelitySettings").get(WorldServerFidelityNames.getRight(m_fidelity));
 }
 
+bool WorldServer::shouldExpire() {
+  if (!m_clientInfo.empty()) {
+    m_expiryTimer.reset();
+    return false;
+  }
+
+  return m_expiryTimer.ready();
+}
+
+void WorldServer::setExpiryTime(float expiryTime) {
+  m_expiryTimer = GameTimer(expiryTime);
+}
+
 void WorldServer::update(float dt) {
   ++m_currentStep;
   for (auto const& pair : m_clientInfo)
@@ -627,6 +645,8 @@ void WorldServer::update(float dt) {
   for (auto& pair : m_clientInfo)
     pair.second->pendingForward = false;
 
+  m_expiryTimer.tick(dt);
+
   LogMap::set(strf("server_{}_entities", m_worldId), strf("{} in {} sectors", m_entityMap->size(), m_tileArray->loadedSectorCount()));
   LogMap::set(strf("server_{}_time", m_worldId), strf("age = {:4.2f}, day = {:4.2f}/{:4.2f}s", epochTime(), timeOfDay(), dayLength()));
   LogMap::set(strf("server_{}_active_liquid", m_worldId), m_liquidEngine->activeCells());
diff --git a/source/game/StarWorldServer.hpp b/source/game/StarWorldServer.hpp
index 66a21d3..b8f3965 100644
--- a/source/game/StarWorldServer.hpp
+++ b/source/game/StarWorldServer.hpp
@@ -14,6 +14,7 @@
 #include "StarLuaRoot.hpp"
 #include "StarWorldRenderData.hpp"
 #include "StarWarping.hpp"
+#include "StarRpcThreadPromise.hpp"
 
 namespace Star {
 
@@ -98,6 +99,8 @@ public:
   void handleIncomingPackets(ConnectionId clientId, List<PacketPtr> const& packets);
   List<PacketPtr> getOutgoingPackets(ConnectionId clientId);
 
+  Maybe<Json> receiveMessage(ConnectionId fromConnection, String const& message, JsonArray const& args);
+
   void startFlyingSky(bool enterHyperspace, bool startInWarp);
   void stopFlyingSkyAt(SkyParameters const& destination);
   void setOrbitalSky(SkyParameters const& destination);
@@ -106,6 +109,9 @@ public:
   WorldServerFidelity fidelity() const;
   void setFidelity(WorldServerFidelity fidelity);
 
+  bool shouldExpire();
+  void setExpiryTime(float expiryTime);
+
   void update(float dt);
 
   ConnectionId connection() const override;
@@ -379,6 +385,8 @@ private:
   List<PhysicsForceRegion> m_forceRegions;
 
   String m_worldId;
+
+  GameTimer m_expiryTimer;
 };
 
 }
diff --git a/source/game/StarWorldServerThread.cpp b/source/game/StarWorldServerThread.cpp
index e06221e..6928456 100644
--- a/source/game/StarWorldServerThread.cpp
+++ b/source/game/StarWorldServerThread.cpp
@@ -13,7 +13,8 @@ WorldServerThread::WorldServerThread(WorldServerPtr server, WorldId worldId)
     m_worldServer(move(server)),
     m_worldId(move(worldId)),
     m_stop(false),
-    m_errorOccurred(false) {
+    m_errorOccurred(false),
+    m_shouldExpire(true) {
   if (m_worldServer)
     m_worldServer->setWorldId(printWorldId(m_worldId));
 }
@@ -50,6 +51,10 @@ bool WorldServerThread::serverErrorOccurred() {
   return m_errorOccurred;
 }
 
+bool WorldServerThread::shouldExpire() {
+  return m_shouldExpire;
+}
+
 bool WorldServerThread::spawnTargetValid(SpawnTarget const& spawnTarget) {
   try {
     RecursiveMutexLocker locker(m_mutex);
@@ -115,6 +120,12 @@ bool WorldServerThread::hasClient(ConnectionId clientId) const {
   return m_clients.contains(clientId);
 }
 
+bool WorldServerThread::noClients() const {
+  RecursiveMutexLocker locker(m_mutex);
+  return m_clients.empty();
+}
+
+
 List<ConnectionId> WorldServerThread::erroredClients() const {
   RecursiveMutexLocker locker(m_mutex);
   auto unerroredClients = HashSet<ConnectionId>::from(m_worldServer->clientIds());
@@ -165,6 +176,11 @@ void WorldServerThread::setUpdateAction(WorldServerAction updateAction) {
   m_updateAction = updateAction;
 }
 
+void WorldServerThread::passMessages(List<Message>&& messages) {
+  RecursiveMutexLocker locker(m_messageMutex);
+  m_messages.appendAll(move(messages));
+}
+
 WorldChunks WorldServerThread::readChunks() {
   try {
     RecursiveMutexLocker locker(m_mutex);
@@ -256,12 +272,26 @@ void WorldServerThread::update(WorldServerFidelity fidelity) {
   if (!m_pause || *m_pause == false)
     m_worldServer->update(dt);
 
+  List<Message> messages;
+  {
+    RecursiveMutexLocker locker(m_messageMutex);
+    messages = move(m_messages);
+  }
+  for (auto& message : messages) {
+    if (auto resp = m_worldServer->receiveMessage(ServerConnectionId, message.message, message.args))
+      message.promise.fulfill(*resp);
+    else
+      message.promise.fail("Message not handled by world");
+  }
+
   for (auto& clientId : unerroredClientIds) {
     auto outgoingPackets = m_worldServer->getOutgoingPackets(clientId);
     RecursiveMutexLocker queueLocker(m_queueMutex);
     m_outgoingPacketQueue[clientId].appendAll(move(outgoingPackets));
   }
 
+  m_shouldExpire = m_worldServer->shouldExpire();
+
   if (m_updateAction)
     m_updateAction(this, m_worldServer.get());
 }
diff --git a/source/game/StarWorldServerThread.hpp b/source/game/StarWorldServerThread.hpp
index bd13c02..d61c3dc 100644
--- a/source/game/StarWorldServerThread.hpp
+++ b/source/game/StarWorldServerThread.hpp
@@ -3,6 +3,7 @@
 
 #include "StarWorldServer.hpp"
 #include "StarThread.hpp"
+#include "StarRpcThreadPromise.hpp"
 
 namespace Star {
 
@@ -13,6 +14,12 @@ STAR_CLASS(WorldServerThread);
 // the error and trigger the WorldServerThread error state.
 class WorldServerThread : public Thread {
 public:
+  struct Message {
+    String message;
+    JsonArray args;
+    RpcThreadPromiseKeeper<Json> promise;
+  };
+
   typedef function<void(WorldServerThread*, WorldServer*)> WorldServerAction;
 
   WorldServerThread(WorldServerPtr server, WorldId worldId);
@@ -28,6 +35,7 @@ public:
   // An exception occurred from the actual WorldServer itself and the
   // WorldServerThread has stopped running.
   bool serverErrorOccurred();
+  bool shouldExpire();
 
   bool spawnTargetValid(SpawnTarget const& spawnTarget);
 
@@ -37,6 +45,7 @@ public:
 
   List<ConnectionId> clients() const;
   bool hasClient(ConnectionId clientId) const;
+  bool noClients() const;
 
   // Clients that have caused an error with incoming packets are removed from
   // the world and no further packets are handled from them.  They are still
@@ -61,6 +70,9 @@ public:
   // also in a thread safe context.
   void setUpdateAction(WorldServerAction updateAction);
 
+  // 
+  void passMessages(List<Message>&& messages);
+
   // Syncs all active sectors to disk and reads the full content of the world
   // into memory, useful for the ship.
   WorldChunks readChunks();
@@ -84,9 +96,13 @@ private:
   Map<ConnectionId, List<PacketPtr>> m_incomingPacketQueue;
   Map<ConnectionId, List<PacketPtr>> m_outgoingPacketQueue;
 
+  mutable RecursiveMutex m_messageMutex;
+  List<Message> m_messages;
+
   atomic<bool> m_stop;
   shared_ptr<const atomic<bool>> m_pause;
   mutable atomic<bool> m_errorOccurred;
+  mutable atomic<bool> m_shouldExpire;
 };
 
 }
diff --git a/source/game/scripting/StarLuaGameConverters.hpp b/source/game/scripting/StarLuaGameConverters.hpp
index ff84792..6188bf1 100644
--- a/source/game/scripting/StarLuaGameConverters.hpp
+++ b/source/game/scripting/StarLuaGameConverters.hpp
@@ -10,6 +10,7 @@
 #include "StarBehaviorState.hpp"
 #include "StarSystemWorld.hpp"
 #include "StarDrawable.hpp"
+#include "StarRpcThreadPromise.hpp"
 
 namespace Star {
 
@@ -33,6 +34,14 @@ struct LuaUserDataMethods<RpcPromise<T>> {
   static LuaMethods<RpcPromise<T>> make();
 };
 
+template <typename T>
+struct LuaConverter<RpcThreadPromise<T>> : LuaUserDataConverter<RpcThreadPromise<T>> {};
+
+template <typename T>
+struct LuaUserDataMethods<RpcThreadPromise<T>> {
+  static LuaMethods<RpcThreadPromise<T>> make();
+};
+
 template <>
 struct LuaConverter<PlatformerAStar::Path> {
   static LuaValue from(LuaEngine& engine, PlatformerAStar::Path const& path);
@@ -115,6 +124,16 @@ LuaMethods<RpcPromise<T>> LuaUserDataMethods<RpcPromise<T>>::make() {
   return methods;
 }
 
+template <typename T>
+LuaMethods<RpcThreadPromise<T>> LuaUserDataMethods<RpcThreadPromise<T>>::make() {
+  LuaMethods<RpcThreadPromise<T>> methods;
+  methods.template registerMethodWithSignature<bool, RpcThreadPromise<T>&>("finished", mem_fn(&RpcThreadPromise<T>::finished));
+  methods.template registerMethodWithSignature<bool, RpcThreadPromise<T>&>("succeeded", mem_fn(&RpcThreadPromise<T>::succeeded));
+  methods.template registerMethodWithSignature<Maybe<T>, RpcThreadPromise<T>&>("result", mem_fn(&RpcThreadPromise<T>::result));
+  methods.template registerMethodWithSignature<Maybe<String>, RpcThreadPromise<T>&>("error", mem_fn(&RpcThreadPromise<T>::error));
+  return methods;
+}
+
 template <>
 struct LuaConverter<Collection> {
   static LuaValue from(LuaEngine& engine, Collection const& c);
diff --git a/source/game/scripting/StarUniverseServerLuaBindings.cpp b/source/game/scripting/StarUniverseServerLuaBindings.cpp
index b055b76..9101be5 100644
--- a/source/game/scripting/StarUniverseServerLuaBindings.cpp
+++ b/source/game/scripting/StarUniverseServerLuaBindings.cpp
@@ -18,6 +18,7 @@ LuaCallbacks LuaBindings::makeUniverseServerCallbacks(UniverseServer* universe)
   callbacks.registerCallbackWithSignature<bool, ConnectionId>("isAdmin", bind(UniverseServerCallbacks::isAdmin, universe, _1));
   callbacks.registerCallbackWithSignature<bool, ConnectionId>("isPvp", bind(UniverseServerCallbacks::isPvp, universe, _1));
   callbacks.registerCallbackWithSignature<void, ConnectionId, bool>("setPvp", bind(UniverseServerCallbacks::setPvp, universe, _1, _2));
+  callbacks.registerCallbackWithSignature<RpcThreadPromise<Json>, LuaEngine&, String, String, LuaVariadic<Json>>("sendWorldMessage", bind(UniverseServerCallbacks::sendWorldMessage, universe, _1, _2, _3, _4));
 
   return callbacks;
 }
@@ -107,4 +108,8 @@ void LuaBindings::UniverseServerCallbacks::setPvp(UniverseServer* universe, Conn
   universe->setPvp(client, setPvpTo);
 }
 
+RpcThreadPromise<Json> LuaBindings::UniverseServerCallbacks::sendWorldMessage(UniverseServer* universe, LuaEngine& engine, String const& worldId, String const& message, LuaVariadic<Json> args) {
+  return universe->sendWorldMessage(parseWorldId(worldId), message, JsonArray::from(move(args)));
+}
+
 }
diff --git a/source/game/scripting/StarUniverseServerLuaBindings.hpp b/source/game/scripting/StarUniverseServerLuaBindings.hpp
index f94f285..5eb1674 100644
--- a/source/game/scripting/StarUniverseServerLuaBindings.hpp
+++ b/source/game/scripting/StarUniverseServerLuaBindings.hpp
@@ -3,6 +3,7 @@
 
 #include "StarLua.hpp"
 #include "StarGameTypes.hpp"
+#include "StarRpcThreadPromise.hpp"
 
 namespace Star {
 
@@ -22,6 +23,7 @@ namespace LuaBindings {
     bool isAdmin(UniverseServer* universe, ConnectionId arg1);
     bool isPvp(UniverseServer* universe, ConnectionId arg1);
     void setPvp(UniverseServer* universe, ConnectionId arg1, Maybe<bool> arg2);
+    RpcThreadPromise<Json> sendWorldMessage(UniverseServer* universe, LuaEngine& engine, String const& worldId, String const& message, LuaVariadic<Json> args);
   }
 }
 }
diff --git a/source/game/scripting/StarWorldLuaBindings.cpp b/source/game/scripting/StarWorldLuaBindings.cpp
index 8d7d1bd..da4f7c8 100644
--- a/source/game/scripting/StarWorldLuaBindings.cpp
+++ b/source/game/scripting/StarWorldLuaBindings.cpp
@@ -390,6 +390,9 @@ namespace LuaBindings {
       callbacks.registerCallbackWithSignature<void, double>("setSkyTime", [serverWorld](double skyTime) {
           return serverWorld->sky()->setEpochTime(skyTime);
         });
+
+      callbacks.registerCallback("setExpiryTime", [serverWorld](float expiryTime) { serverWorld->setExpiryTime(expiryTime); });
+
       callbacks.registerCallback("flyingType", [serverWorld]() -> String { return FlyingTypeNames.getRight(serverWorld->sky()->flyingType()); });
       callbacks.registerCallback("warpPhase", [serverWorld]() -> String { return WarpPhaseNames.getRight(serverWorld->sky()->warpPhase()); });
       callbacks.registerCallback("setUniverseFlag", [serverWorld](String flagName) { return serverWorld->universeSettings()->setFlag(flagName); });