diff --git a/src/command_line.cc b/src/command_line.cc
index 769f156c..9b5b0bd9 100644
--- a/src/command_line.cc
+++ b/src/command_line.cc
@@ -5,7 +5,6 @@
 #include "file_consumer.h"
 #include "include_complete.h"
 #include "indexer.h"
-#include "ipc_manager.h"
 #include "language_server_api.h"
 #include "lex_utils.h"
 #include "lru_cache.h"
@@ -16,6 +15,7 @@
 #include "project.h"
 #include "query.h"
 #include "query_utils.h"
+#include "queue_manager.h"
 #include "serializer.h"
 #include "standard_includes.h"
 #include "test.h"
@@ -76,7 +76,7 @@ void EmitDiagnostics(WorkingFiles* working_files,
   Out_TextDocumentPublishDiagnostics out;
   out.params.uri = lsDocumentUri::FromPath(path);
   out.params.diagnostics = diagnostics;
-  IpcManager::WriteStdout(IpcId::TextDocumentPublishDiagnostics, out);
+  QueueManager::WriteStdout(IpcId::TextDocumentPublishDiagnostics, out);
 
   // Cache diagnostics so we can show fixits.
   working_files->DoActionOnFile(path, [&](WorkingFile* working_file) {
@@ -88,8 +88,9 @@ void EmitDiagnostics(WorkingFiles* working_files,
 REGISTER_IPC_MESSAGE(Ipc_CancelRequest);
 
 // Send indexing progress to client if reporting is enabled.
-void EmitProgress(Config* config, QueueManager* queue) {
+void EmitProgress(Config* config) {
   if (config->enableProgressReports) {
+    auto* queue = QueueManager::instance();
     Out_Progress out;
     out.params.indexRequestCount = queue->index_request.Size();
     out.params.doIdMapCount = queue->do_id_map.Size();
@@ -97,7 +98,7 @@ void EmitProgress(Config* config, QueueManager* queue) {
     out.params.onIdMappedCount = queue->on_id_mapped.Size();
     out.params.onIndexedCount = queue->on_indexed.Size();
 
-    IpcManager::WriteStdout(IpcId::Unknown, out);
+    QueueManager::WriteStdout(IpcId::Unknown, out);
   }
 }
 
@@ -307,7 +308,6 @@ std::vector<Index_DoIdMap> DoParseFile(
 // real-time indexing.
 // TODO: add option to disable this.
 void IndexWithTuFromCodeCompletion(
-    QueueManager* queue,
     FileConsumer::SharedState* file_consumer_shared,
     ClangTranslationUnit* tu,
     const std::vector<CXUnsavedFile>& file_contents,
@@ -335,7 +335,7 @@ void IndexWithTuFromCodeCompletion(
   LOG_IF_S(WARNING, result.size() > 1)
       << "Code completion index update generated more than one index";
 
-  queue->do_id_map.EnqueueAll(std::move(result));
+  QueueManager::instance()->do_id_map.EnqueueAll(std::move(result));
 }
 
 std::vector<Index_DoIdMap> ParseFile(
@@ -366,11 +366,11 @@ std::vector<Index_DoIdMap> ParseFile(
 
 bool IndexMain_DoParse(Config* config,
                        WorkingFiles* working_files,
-                       QueueManager* queue,
                        FileConsumer::SharedState* file_consumer_shared,
                        TimestampManager* timestamp_manager,
                        ImportManager* import_manager,
                        ClangIndex* index) {
+  auto* queue = QueueManager::instance();
   optional<Index_Request> request = queue->index_request.TryDequeue();
   if (!request)
     return false;
@@ -392,8 +392,8 @@ bool IndexMain_DoParse(Config* config,
 }
 
 bool IndexMain_DoCreateIndexUpdate(Config* config,
-                                   QueueManager* queue,
                                    TimestampManager* timestamp_manager) {
+  auto* queue = QueueManager::instance();
   optional<Index_OnIdMapped> response = queue->on_id_mapped.TryDequeue();
   if (!response)
     return false;
@@ -457,7 +457,8 @@ bool IndexMain_DoCreateIndexUpdate(Config* config,
   return true;
 }
 
-bool IndexMain_LoadPreviousIndex(Config* config, QueueManager* queue) {
+bool IndexMain_LoadPreviousIndex(Config* config) {
+  auto* queue = QueueManager::instance();
   optional<Index_DoIdMap> response = queue->load_previous_index.TryDequeue();
   if (!response)
     return false;
@@ -471,7 +472,8 @@ bool IndexMain_LoadPreviousIndex(Config* config, QueueManager* queue) {
   return true;
 }
 
-bool IndexMergeIndexUpdates(QueueManager* queue) {
+bool IndexMergeIndexUpdates() {
+  auto* queue = QueueManager::instance();
   optional<Index_OnIndexed> root = queue->on_indexed.TryDequeue();
   if (!root)
     return false;
@@ -501,9 +503,8 @@ WorkThread::Result IndexMain(Config* config,
                              ImportManager* import_manager,
                              Project* project,
                              WorkingFiles* working_files,
-                             MultiQueueWaiter* waiter,
-                             QueueManager* queue) {
-  EmitProgress(config, queue);
+                             MultiQueueWaiter* waiter) {
+  EmitProgress(config);
 
   // Build one index per-indexer, as building the index acquires a global lock.
   ClangIndex index;
@@ -517,19 +518,21 @@ WorkThread::Result IndexMain(Config* config,
   // work. Running both also lets the user query the partially constructed
   // index.
   bool did_parse =
-      IndexMain_DoParse(config, working_files, queue, file_consumer_shared,
+      IndexMain_DoParse(config, working_files, file_consumer_shared,
                         timestamp_manager, import_manager, &index);
 
   bool did_create_update =
-      IndexMain_DoCreateIndexUpdate(config, queue, timestamp_manager);
+      IndexMain_DoCreateIndexUpdate(config, timestamp_manager);
 
-  bool did_load_previous = IndexMain_LoadPreviousIndex(config, queue);
+  bool did_load_previous = IndexMain_LoadPreviousIndex(config);
 
   // Nothing to index and no index updates to create, so join some already
   // created index updates to reduce work on querydb thread.
   bool did_merge = false;
   if (!did_parse && !did_create_update && !did_load_previous)
-    did_merge = IndexMergeIndexUpdates(queue);
+    did_merge = IndexMergeIndexUpdates();
+
+  auto* queue = QueueManager::instance();
 
   // We didn't do any work, so wait for a notification.
   if (!did_parse && !did_create_update && !did_merge && !did_load_previous) {
@@ -544,10 +547,10 @@ WorkThread::Result IndexMain(Config* config,
 bool QueryDb_ImportMain(Config* config,
                         QueryDatabase* db,
                         ImportManager* import_manager,
-                        QueueManager* queue,
                         SemanticHighlightSymbolCache* semantic_cache,
                         WorkingFiles* working_files) {
-  EmitProgress(config, queue);
+  auto* queue = QueueManager::instance();
+  EmitProgress(config);
 
   bool did_work = false;
 
@@ -685,7 +688,6 @@ bool QueryDbMainLoop(Config* config,
                      QueryDatabase* db,
                      bool* exit_when_idle,
                      MultiQueueWaiter* waiter,
-                     QueueManager* queue,
                      Project* project,
                      FileConsumer::SharedState* file_consumer_shared,
                      ImportManager* import_manager,
@@ -697,12 +699,11 @@ bool QueryDbMainLoop(Config* config,
                      CodeCompleteCache* global_code_complete_cache,
                      CodeCompleteCache* non_global_code_complete_cache,
                      CodeCompleteCache* signature_cache) {
-  IpcManager* ipc = IpcManager::instance();
-
+  auto* queue = QueueManager::instance();
   bool did_work = false;
 
   std::vector<std::unique_ptr<BaseIpcMessage>> messages =
-      ipc->for_querydb.DequeueAll();
+      queue->for_querydb.DequeueAll();
   for (auto& message : messages) {
     did_work = true;
 
@@ -722,7 +723,7 @@ bool QueryDbMainLoop(Config* config,
   // TODO: consider rate-limiting and checking for IPC messages so we don't
   // block requests / we can serve partial requests.
 
-  if (QueryDb_ImportMain(config, db, import_manager, queue, semantic_cache,
+  if (QueryDb_ImportMain(config, db, import_manager, semantic_cache,
                          working_files)) {
     did_work = true;
   }
@@ -732,8 +733,7 @@ bool QueryDbMainLoop(Config* config,
 
 void RunQueryDbThread(const std::string& bin_name,
                       Config* config,
-                      MultiQueueWaiter* waiter,
-                      QueueManager* queue) {
+                      MultiQueueWaiter* waiter) {
   bool exit_when_idle = false;
   Project project;
   SemanticHighlightSymbolCache semantic_cache;
@@ -744,7 +744,7 @@ void RunQueryDbThread(const std::string& bin_name,
       config, &project, &working_files,
       std::bind(&EmitDiagnostics, &working_files, std::placeholders::_1,
                 std::placeholders::_2),
-      std::bind(&IndexWithTuFromCodeCompletion, queue, &file_consumer_shared,
+      std::bind(&IndexWithTuFromCodeCompletion, &file_consumer_shared,
                 std::placeholders::_1, std::placeholders::_2,
                 std::placeholders::_3, std::placeholders::_4));
 
@@ -762,7 +762,6 @@ void RunQueryDbThread(const std::string& bin_name,
     handler->db = &db;
     handler->exit_when_idle = &exit_when_idle;
     handler->waiter = waiter;
-    handler->queue = queue;
     handler->project = &project;
     handler->file_consumer_shared = &file_consumer_shared;
     handler->import_manager = &import_manager;
@@ -781,11 +780,10 @@ void RunQueryDbThread(const std::string& bin_name,
   SetCurrentThreadName("querydb");
   while (true) {
     bool did_work = QueryDbMainLoop(
-        config, &db, &exit_when_idle, waiter, queue, &project,
-        &file_consumer_shared, &import_manager, &timestamp_manager,
-        &semantic_cache, &working_files, &clang_complete, &include_complete,
-        global_code_complete_cache.get(), non_global_code_complete_cache.get(),
-        signature_cache.get());
+        config, &db, &exit_when_idle, waiter, &project, &file_consumer_shared,
+        &import_manager, &timestamp_manager, &semantic_cache, &working_files,
+        &clang_complete, &include_complete, global_code_complete_cache.get(),
+        non_global_code_complete_cache.get(), signature_cache.get());
 
     // No more work left and exit request. Exit.
     if (!did_work && exit_when_idle && WorkThread::num_active_threads == 0) {
@@ -797,7 +795,8 @@ void RunQueryDbThread(const std::string& bin_name,
     FreeUnusedMemory();
 
     if (!did_work) {
-      waiter->Wait({&IpcManager::instance()->for_querydb, &queue->do_id_map,
+      auto* queue = QueueManager::instance();
+      waiter->Wait({&QueueManager::instance()->for_querydb, &queue->do_id_map,
                     &queue->on_indexed});
     }
   }
@@ -833,8 +832,7 @@ void LaunchStdinLoop(Config* config,
   std::cin.tie(nullptr);
 
   WorkThread::StartThread("stdin", [request_times]() {
-    IpcManager* ipc = IpcManager::instance();
-
+    auto* queue = QueueManager::instance();
     std::unique_ptr<BaseIpcMessage> message =
         MessageRegistry::instance()->ReadMessageFromStdin(
             g_log_stdin_stdout_to_stderr);
@@ -867,7 +865,7 @@ void LaunchStdinLoop(Config* config,
         // loop to exit the thread. If we keep parsing input stdin is likely
         // closed so cquery will exit.
         LOG_S(INFO) << "cquery will exit when all threads are idle";
-        ipc->for_querydb.Enqueue(std::move(message));
+        queue->for_querydb.Enqueue(std::move(message));
         return WorkThread::Result::ExitThread;
       }
 
@@ -899,7 +897,7 @@ void LaunchStdinLoop(Config* config,
       case IpcId::CqueryDerived:
       case IpcId::CqueryIndexFile:
       case IpcId::CqueryQueryDbWaitForIdleIndexer: {
-        ipc->for_querydb.Enqueue(std::move(message));
+        queue->for_querydb.Enqueue(std::move(message));
         break;
       }
 
@@ -915,15 +913,13 @@ void LaunchStdinLoop(Config* config,
 }
 
 void LaunchStdoutThread(std::unordered_map<IpcId, Timer>* request_times,
-                        MultiQueueWaiter* waiter,
-                        QueueManager* queue) {
+                        MultiQueueWaiter* waiter) {
   WorkThread::StartThread("stdout", [=]() {
-    IpcManager* ipc = IpcManager::instance();
+    auto* queue = QueueManager::instance();
 
-    std::vector<IpcManager::StdoutMessage> messages =
-        ipc->for_stdout.DequeueAll();
+    std::vector<Stdout_Request> messages = queue->for_stdout.DequeueAll();
     if (messages.empty()) {
-      waiter->Wait({&ipc->for_stdout});
+      waiter->Wait({&queue->for_stdout});
       return queue->HasWork() ? WorkThread::Result::MoreWork
                               : WorkThread::Result::NoWork;
     }
@@ -955,18 +951,17 @@ void LaunchStdoutThread(std::unordered_map<IpcId, Timer>* request_times,
 void LanguageServerMain(const std::string& bin_name,
                         Config* config,
                         MultiQueueWaiter* waiter) {
-  QueueManager queue(waiter);
   std::unordered_map<IpcId, Timer> request_times;
 
   LaunchStdinLoop(config, &request_times);
 
   // We run a dedicated thread for writing to stdout because there can be an
   // unknown number of delays when output information.
-  LaunchStdoutThread(&request_times, waiter, &queue);
+  LaunchStdoutThread(&request_times, waiter);
 
   // Start querydb which takes over this thread. The querydb will launch
   // indexer threads as needed.
-  RunQueryDbThread(bin_name, config, waiter, &queue);
+  RunQueryDbThread(bin_name, config, waiter);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -997,7 +992,7 @@ int main(int argc, char** argv) {
   loguru::init(argc, argv);
 
   MultiQueueWaiter waiter;
-  IpcManager::CreateInstance(&waiter);
+  QueueManager::CreateInstance(&waiter);
 
   // bool loop = true;
   // while (loop)
diff --git a/src/entry_points.h b/src/entry_points.h
index 498a7a02..1e7e3412 100644
--- a/src/entry_points.h
+++ b/src/entry_points.h
@@ -3,7 +3,7 @@
 #include "config.h"
 #include "file_consumer.h"
 #include "import_manager.h"
-#include "ipc_manager.h"
+#include "queue_manager.h"
 #include "project.h"
 #include "semantic_highlight_symbol_cache.h"
 #include "threaded_queue.h"
@@ -16,7 +16,6 @@
 bool QueryDb_ImportMain(Config* config,
                         QueryDatabase* db,
                         ImportManager* import_manager,
-                        QueueManager* queue,
                         SemanticHighlightSymbolCache* semantic_cache,
                         WorkingFiles* working_files);
 
@@ -26,5 +25,4 @@ WorkThread::Result IndexMain(Config* config,
                              ImportManager* import_manager,
                              Project* project,
                              WorkingFiles* working_files,
-                             MultiQueueWaiter* waiter,
-                             QueueManager* queue);
\ No newline at end of file
+                             MultiQueueWaiter* waiter);
\ No newline at end of file
diff --git a/src/match.cc b/src/match.cc
index dc722d5d..62fb7c5e 100644
--- a/src/match.cc
+++ b/src/match.cc
@@ -1,6 +1,6 @@
 #include "match.h"
 
-#include "ipc_manager.h"
+#include "queue_manager.h"
 #include "language_server_api.h"
 
 #include <doctest/doctest.h>
@@ -34,7 +34,7 @@ optional<Matcher> Matcher::Create(const std::string& search) {
     out.params.type = lsMessageType::Error;
     out.params.message = "cquery: Parsing EMCAScript regex \"" + search +
                          "\" failed; " + e.what();
-    IpcManager::WriteStdout(IpcId::Unknown, out);
+    QueueManager::WriteStdout(IpcId::Unknown, out);
     return nullopt;
   }
 }
diff --git a/src/message_handler.cc b/src/message_handler.cc
index 95a57e10..c67e2e27 100644
--- a/src/message_handler.cc
+++ b/src/message_handler.cc
@@ -44,7 +44,7 @@ bool FindFileOrFail(QueryDatabase* db,
     out.id = *id;
     out.error.code = lsErrorCodes::InternalError;
     out.error.message = "Unable to find file " + absolute_path;
-    IpcManager::WriteStdout(IpcId::Unknown, out);
+    QueueManager::WriteStdout(IpcId::Unknown, out);
   }
 
   return false;
@@ -59,7 +59,7 @@ void EmitInactiveLines(WorkingFile* working_file,
     if (ls_skipped)
       out.params.inactiveRegions.push_back(*ls_skipped);
   }
-  IpcManager::WriteStdout(IpcId::CqueryPublishInactiveRegions, out);
+  QueueManager::WriteStdout(IpcId::CqueryPublishInactiveRegions, out);
 }
 
 void EmitSemanticHighlighting(QueryDatabase* db,
@@ -145,7 +145,7 @@ void EmitSemanticHighlighting(QueryDatabase* db,
   out.params.uri = lsDocumentUri::FromPath(working_file->filename);
   for (auto& entry : grouped_symbols)
     out.params.symbols.push_back(entry.second);
-  IpcManager::WriteStdout(IpcId::CqueryPublishSemanticHighlighting, out);
+  QueueManager::WriteStdout(IpcId::CqueryPublishSemanticHighlighting, out);
 }
 
 bool ShouldIgnoreFileForIndexing(const std::string& path) {
diff --git a/src/message_handler.h b/src/message_handler.h
index 669c6a8b..d2af7985 100644
--- a/src/message_handler.h
+++ b/src/message_handler.h
@@ -6,7 +6,7 @@
 #include "config.h"
 #include "import_manager.h"
 #include "include_complete.h"
-#include "ipc_manager.h"
+#include "queue_manager.h"
 #include "project.h"
 #include "query.h"
 #include "semantic_highlight_symbol_cache.h"
@@ -32,7 +32,6 @@ struct MessageHandler {
   QueryDatabase* db = nullptr;
   bool* exit_when_idle = nullptr;
   MultiQueueWaiter* waiter = nullptr;
-  QueueManager* queue = nullptr;
   Project* project = nullptr;
   FileConsumer::SharedState* file_consumer_shared = nullptr;
   ImportManager* import_manager = nullptr;
diff --git a/src/messages/cquery_base.cc b/src/messages/cquery_base.cc
index 6ba40b88..d2a20374 100644
--- a/src/messages/cquery_base.cc
+++ b/src/messages/cquery_base.cc
@@ -39,7 +39,7 @@ struct CqueryBaseHandler : BaseMessageHandler<Ipc_CqueryBase> {
         out.result = GetLsLocations(db, working_files, locations);
       }
     }
-    IpcManager::WriteStdout(IpcId::CqueryBase, out);
+    QueueManager::WriteStdout(IpcId::CqueryBase, out);
   }
 };
 REGISTER_MESSAGE_HANDLER(CqueryBaseHandler);
diff --git a/src/messages/cquery_call_tree.cc b/src/messages/cquery_call_tree.cc
index 0eec9ae8..429d5e06 100644
--- a/src/messages/cquery_call_tree.cc
+++ b/src/messages/cquery_call_tree.cc
@@ -197,7 +197,7 @@ struct CqueryCallTreeInitialHandler
       }
     }
 
-    IpcManager::WriteStdout(IpcId::CqueryCallTreeInitial, out);
+    QueueManager::WriteStdout(IpcId::CqueryCallTreeInitial, out);
   }
 };
 REGISTER_MESSAGE_HANDLER(CqueryCallTreeInitialHandler);
@@ -212,7 +212,7 @@ struct CqueryCallTreeExpandHandler
     if (func_id != db->usr_to_func.end())
       out.result = BuildExpandCallTree(db, working_files, func_id->second);
 
-    IpcManager::WriteStdout(IpcId::CqueryCallTreeExpand, out);
+    QueueManager::WriteStdout(IpcId::CqueryCallTreeExpand, out);
   }
 };
 REGISTER_MESSAGE_HANDLER(CqueryCallTreeExpandHandler);
diff --git a/src/messages/cquery_callers.cc b/src/messages/cquery_callers.cc
index 219e54a9..f7f94656 100644
--- a/src/messages/cquery_callers.cc
+++ b/src/messages/cquery_callers.cc
@@ -37,7 +37,7 @@ struct CqueryCallersHandler : BaseMessageHandler<Ipc_CqueryCallers> {
         out.result = GetLsLocations(db, working_files, locations);
       }
     }
-    IpcManager::WriteStdout(IpcId::CqueryCallers, out);
+    QueueManager::WriteStdout(IpcId::CqueryCallers, out);
   }
 };
 REGISTER_MESSAGE_HANDLER(CqueryCallersHandler);
diff --git a/src/messages/cquery_derived.cc b/src/messages/cquery_derived.cc
index 3c1976df..bbd20eb5 100644
--- a/src/messages/cquery_derived.cc
+++ b/src/messages/cquery_derived.cc
@@ -37,7 +37,7 @@ struct CqueryDerivedHandler : BaseMessageHandler<Ipc_CqueryDerived> {
         out.result = GetLsLocations(db, working_files, locations);
       }
     }
-    IpcManager::WriteStdout(IpcId::CqueryDerived, out);
+    QueueManager::WriteStdout(IpcId::CqueryDerived, out);
   }
 };
 REGISTER_MESSAGE_HANDLER(CqueryDerivedHandler);
diff --git a/src/messages/cquery_freshen_index.cc b/src/messages/cquery_freshen_index.cc
index 2fb35c3a..f5bf7083 100644
--- a/src/messages/cquery_freshen_index.cc
+++ b/src/messages/cquery_freshen_index.cc
@@ -37,6 +37,8 @@ struct CqueryFreshenIndexHandler : MessageHandler {
         file_consumer_shared->Reset(file.def->path);
     }
 
+    auto* queue = QueueManager::instance();
+
     // Send index requests for every file.
     project->ForAllFilteredFiles(config, [&](int i,
                                              const Project::Entry& entry) {
diff --git a/src/messages/cquery_index_file.cc b/src/messages/cquery_index_file.cc
index fa86b67a..c0b13e47 100644
--- a/src/messages/cquery_index_file.cc
+++ b/src/messages/cquery_index_file.cc
@@ -23,7 +23,7 @@ REGISTER_IPC_MESSAGE(Ipc_CqueryIndexFile);
 
 struct CqueryIndexFileHandler : BaseMessageHandler<Ipc_CqueryIndexFile> {
   void Run(Ipc_CqueryIndexFile* request) override {
-    queue->index_request.Enqueue(Index_Request(
+    QueueManager::instance()->index_request.Enqueue(Index_Request(
         NormalizePath(request->params.path), request->params.args,
         request->params.is_interactive, request->params.contents));
   }
diff --git a/src/messages/cquery_querydb_wait_for_idle_indexer.cc b/src/messages/cquery_querydb_wait_for_idle_indexer.cc
index 9ede93b7..564a119b 100644
--- a/src/messages/cquery_querydb_wait_for_idle_indexer.cc
+++ b/src/messages/cquery_querydb_wait_for_idle_indexer.cc
@@ -21,9 +21,9 @@ struct CqueryQueryDbWaitForIdleIndexerHandler : MessageHandler {
     while (true) {
       bool has_work = false;
       has_work |= import_manager->HasActiveQuerydbImports();
-      has_work |= queue->HasWork();
-      has_work |= QueryDb_ImportMain(config, db, import_manager, queue,
-                                     semantic_cache, working_files);
+      has_work |= QueueManager::instance()->HasWork();
+      has_work |= QueryDb_ImportMain(config, db, import_manager, semantic_cache,
+                                     working_files);
       if (!has_work)
         ++idle_count;
       else
diff --git a/src/messages/cquery_type_hierarchy_tree.cc b/src/messages/cquery_type_hierarchy_tree.cc
index 2c791088..61ba84cb 100644
--- a/src/messages/cquery_type_hierarchy_tree.cc
+++ b/src/messages/cquery_type_hierarchy_tree.cc
@@ -190,7 +190,7 @@ struct CqueryTypeHierarchyTreeHandler
       }
     }
 
-    IpcManager::WriteStdout(IpcId::CqueryTypeHierarchyTree, out);
+    QueueManager::WriteStdout(IpcId::CqueryTypeHierarchyTree, out);
   }
 };
 REGISTER_MESSAGE_HANDLER(CqueryTypeHierarchyTreeHandler);
diff --git a/src/messages/cquery_vars.cc b/src/messages/cquery_vars.cc
index 08490c1a..eba89fcd 100644
--- a/src/messages/cquery_vars.cc
+++ b/src/messages/cquery_vars.cc
@@ -32,7 +32,7 @@ struct CqueryVarsHandler : BaseMessageHandler<Ipc_CqueryVars> {
         out.result = GetLsLocations(db, working_files, locations);
       }
     }
-    IpcManager::WriteStdout(IpcId::CqueryVars, out);
+    QueueManager::WriteStdout(IpcId::CqueryVars, out);
   }
 };
 REGISTER_MESSAGE_HANDLER(CqueryVarsHandler);
diff --git a/src/messages/initialize.cc b/src/messages/initialize.cc
index 4110f9d2..006135e3 100644
--- a/src/messages/initialize.cc
+++ b/src/messages/initialize.cc
@@ -141,7 +141,7 @@ struct InitializeHandler : BaseMessageHandler<Ipc_InitializeRequest> {
       out.result.capabilities.documentLinkProvider = lsDocumentLinkOptions();
       out.result.capabilities.documentLinkProvider->resolveProvider = false;
 
-      IpcManager::WriteStdout(IpcId::Initialize, out);
+      QueueManager::WriteStdout(IpcId::Initialize, out);
 
       // Set project root.
       config->projectRoot = NormalizePath(request->params.rootUri->GetPath());
@@ -174,8 +174,7 @@ struct InitializeHandler : BaseMessageHandler<Ipc_InitializeRequest> {
       for (int i = 0; i < config->indexerCount; ++i) {
         WorkThread::StartThread("indexer" + std::to_string(i), [=]() {
           return IndexMain(config, file_consumer_shared, timestamp_manager,
-                           import_manager, project, working_files, waiter,
-                           queue);
+                           import_manager, project, working_files, waiter);
         });
       }
 
@@ -183,6 +182,7 @@ struct InitializeHandler : BaseMessageHandler<Ipc_InitializeRequest> {
       // files, because that takes a long time.
       include_complete->Rescan();
 
+      auto* queue = QueueManager::instance();
       time.Reset();
       project->ForAllFilteredFiles(
           config, [&](int i, const Project::Entry& entry) {
diff --git a/src/messages/text_document_code_action.cc b/src/messages/text_document_code_action.cc
index 5f31e494..e8fdb2c9 100644
--- a/src/messages/text_document_code_action.cc
+++ b/src/messages/text_document_code_action.cc
@@ -531,7 +531,7 @@ struct TextDocumentCodeActionHandler
       }
     }
 
-    IpcManager::WriteStdout(IpcId::TextDocumentCodeAction, out);
+    QueueManager::WriteStdout(IpcId::TextDocumentCodeAction, out);
   }
 };
 REGISTER_MESSAGE_HANDLER(TextDocumentCodeActionHandler);
diff --git a/src/messages/text_document_code_lens.cc b/src/messages/text_document_code_lens.cc
index 14a914c2..2983b27b 100644
--- a/src/messages/text_document_code_lens.cc
+++ b/src/messages/text_document_code_lens.cc
@@ -257,7 +257,7 @@ struct TextDocumentCodeLensHandler
       };
     }
 
-    IpcManager::WriteStdout(IpcId::TextDocumentCodeLens, out);
+    QueueManager::WriteStdout(IpcId::TextDocumentCodeLens, out);
   }
 };
 REGISTER_MESSAGE_HANDLER(TextDocumentCodeLensHandler);
diff --git a/src/messages/text_document_completion.cc b/src/messages/text_document_completion.cc
index bee1c923..bdcbd7c6 100644
--- a/src/messages/text_document_completion.cc
+++ b/src/messages/text_document_completion.cc
@@ -145,7 +145,7 @@ struct TextDocumentCompletionHandler : MessageHandler {
       }
 
       FilterCompletionResponse(&out, buffer_line);
-      IpcManager::WriteStdout(IpcId::TextDocumentCompletion, out);
+      QueueManager::WriteStdout(IpcId::TextDocumentCompletion, out);
     } else {
       bool is_global_completion = false;
       std::string existing_completion;
@@ -165,7 +165,7 @@ struct TextDocumentCompletionHandler : MessageHandler {
 
             // Emit completion results.
             FilterCompletionResponse(&out, existing_completion);
-            IpcManager::WriteStdout(IpcId::TextDocumentCompletion, out);
+            QueueManager::WriteStdout(IpcId::TextDocumentCompletion, out);
 
             // Cache completion results.
             if (!is_cached_result) {
diff --git a/src/messages/text_document_definition.cc b/src/messages/text_document_definition.cc
index 99c7621c..f7306e29 100644
--- a/src/messages/text_document_definition.cc
+++ b/src/messages/text_document_definition.cc
@@ -128,7 +128,7 @@ struct TextDocumentDefinitionHandler
       }
     }
 
-    IpcManager::WriteStdout(IpcId::TextDocumentDefinition, out);
+    QueueManager::WriteStdout(IpcId::TextDocumentDefinition, out);
   }
 };
 REGISTER_MESSAGE_HANDLER(TextDocumentDefinitionHandler);
diff --git a/src/messages/text_document_did_close.cc b/src/messages/text_document_did_close.cc
index 5ec49df4..d6e6bc85 100644
--- a/src/messages/text_document_did_close.cc
+++ b/src/messages/text_document_did_close.cc
@@ -21,7 +21,7 @@ struct TextDocumentDidCloseHandler
     // Clear any diagnostics for the file.
     Out_TextDocumentPublishDiagnostics out;
     out.params.uri = request->params.textDocument.uri;
-    IpcManager::WriteStdout(IpcId::TextDocumentPublishDiagnostics, out);
+    QueueManager::WriteStdout(IpcId::TextDocumentPublishDiagnostics, out);
 
     // Remove internal state.
     working_files->OnClose(request->params.textDocument);
diff --git a/src/messages/text_document_did_open.cc b/src/messages/text_document_did_open.cc
index 4534c61f..f0477d31 100644
--- a/src/messages/text_document_did_open.cc
+++ b/src/messages/text_document_did_open.cc
@@ -52,7 +52,7 @@ struct TextDocumentDidOpenHandler
 
     // Submit new index request.
     const Project::Entry& entry = project->FindCompilationEntryForFile(path);
-    queue->index_request.PriorityEnqueue(Index_Request(
+    QueueManager::instance()->index_request.PriorityEnqueue(Index_Request(
         entry.filename, entry.args, true /*is_interactive*/, nullopt));
   }
 };
diff --git a/src/messages/text_document_did_save.cc b/src/messages/text_document_did_save.cc
index 0b081f75..4432def6 100644
--- a/src/messages/text_document_did_save.cc
+++ b/src/messages/text_document_did_save.cc
@@ -39,7 +39,7 @@ struct TextDocumentDidSaveHandler
     //      if so, ignore that index response.
     // TODO: send as priority request
     Project::Entry entry = project->FindCompilationEntryForFile(path);
-    queue->index_request.Enqueue(Index_Request(
+    QueueManager::instance()->index_request.Enqueue(Index_Request(
         entry.filename, entry.args, true /*is_interactive*/, nullopt));
 
     clang_complete->NotifySave(path);
diff --git a/src/messages/text_document_document_link.cc b/src/messages/text_document_document_link.cc
index 918e6bd8..08bb20c1 100644
--- a/src/messages/text_document_document_link.cc
+++ b/src/messages/text_document_document_link.cc
@@ -80,7 +80,7 @@ struct TextDocumentDocumentLinkHandler
       }
     }
 
-    IpcManager::WriteStdout(IpcId::TextDocumentDocumentLink, out);
+    QueueManager::WriteStdout(IpcId::TextDocumentDocumentLink, out);
   }
 };
 REGISTER_MESSAGE_HANDLER(TextDocumentDocumentLinkHandler);
diff --git a/src/messages/text_document_document_symbol.cc b/src/messages/text_document_document_symbol.cc
index ecdcf2c2..ea7958c9 100644
--- a/src/messages/text_document_document_symbol.cc
+++ b/src/messages/text_document_document_symbol.cc
@@ -49,7 +49,7 @@ struct TextDocumentDocumentSymbolHandler
       out.result.push_back(*info);
     }
 
-    IpcManager::WriteStdout(IpcId::TextDocumentDocumentSymbol, out);
+    QueueManager::WriteStdout(IpcId::TextDocumentDocumentSymbol, out);
   }
 };
 REGISTER_MESSAGE_HANDLER(TextDocumentDocumentSymbolHandler);
diff --git a/src/messages/text_document_highlight.cc b/src/messages/text_document_highlight.cc
index ed8c7094..4e988e95 100644
--- a/src/messages/text_document_highlight.cc
+++ b/src/messages/text_document_highlight.cc
@@ -58,7 +58,7 @@ struct TextDocumentDocumentHighlightHandler
       break;
     }
 
-    IpcManager::WriteStdout(IpcId::TextDocumentDocumentHighlight, out);
+    QueueManager::WriteStdout(IpcId::TextDocumentDocumentHighlight, out);
   }
 };
 REGISTER_MESSAGE_HANDLER(TextDocumentDocumentHighlightHandler);
diff --git a/src/messages/text_document_hover.cc b/src/messages/text_document_hover.cc
index 5dd82239..29217489 100644
--- a/src/messages/text_document_hover.cc
+++ b/src/messages/text_document_hover.cc
@@ -107,7 +107,7 @@ struct TextDocumentHoverHandler : BaseMessageHandler<Ipc_TextDocumentHover> {
       }
     }
 
-    IpcManager::WriteStdout(IpcId::TextDocumentHover, out);
+    QueueManager::WriteStdout(IpcId::TextDocumentHover, out);
   }
 };
 REGISTER_MESSAGE_HANDLER(TextDocumentHoverHandler);
diff --git a/src/messages/text_document_references.cc b/src/messages/text_document_references.cc
index 392ebaaa..3294c6f8 100644
--- a/src/messages/text_document_references.cc
+++ b/src/messages/text_document_references.cc
@@ -75,7 +75,7 @@ struct TextDocumentReferencesHandler
       break;
     }
 
-    IpcManager::WriteStdout(IpcId::TextDocumentReferences, out);
+    QueueManager::WriteStdout(IpcId::TextDocumentReferences, out);
   }
 };
 REGISTER_MESSAGE_HANDLER(TextDocumentReferencesHandler);
diff --git a/src/messages/text_document_rename.cc b/src/messages/text_document_rename.cc
index 9433563c..5a5bfaf9 100644
--- a/src/messages/text_document_rename.cc
+++ b/src/messages/text_document_rename.cc
@@ -104,7 +104,7 @@ struct TextDocumentRenameHandler : BaseMessageHandler<Ipc_TextDocumentRename> {
       break;
     }
 
-    IpcManager::WriteStdout(IpcId::TextDocumentRename, out);
+    QueueManager::WriteStdout(IpcId::TextDocumentRename, out);
   }
 };
 REGISTER_MESSAGE_HANDLER(TextDocumentRenameHandler);
diff --git a/src/messages/text_document_signature_help.cc b/src/messages/text_document_signature_help.cc
index a80e06b0..a42aadc1 100644
--- a/src/messages/text_document_signature_help.cc
+++ b/src/messages/text_document_signature_help.cc
@@ -135,7 +135,7 @@ struct TextDocumentSignatureHelpHandler : MessageHandler {
           out.result.activeParameter = active_param;
 
           Timer timer;
-          IpcManager::WriteStdout(IpcId::TextDocumentSignatureHelp, out);
+          QueueManager::WriteStdout(IpcId::TextDocumentSignatureHelp, out);
 
           if (!is_cached_result) {
             signature_cache->WithLock([&]() {
diff --git a/src/messages/workspace_symbol.cc b/src/messages/workspace_symbol.cc
index e2005390..9fb51f0f 100644
--- a/src/messages/workspace_symbol.cc
+++ b/src/messages/workspace_symbol.cc
@@ -97,7 +97,7 @@ struct WorkspaceSymbolHandler : BaseMessageHandler<Ipc_WorkspaceSymbol> {
 
     LOG_S(INFO) << "[querydb] Found " << out.result.size()
                 << " results for query " << query;
-    IpcManager::WriteStdout(IpcId::WorkspaceSymbol, out);
+    QueueManager::WriteStdout(IpcId::WorkspaceSymbol, out);
   }
 };
 REGISTER_MESSAGE_HANDLER(WorkspaceSymbolHandler);
diff --git a/src/ipc_manager.cc b/src/queue_manager.cc
similarity index 82%
rename from src/ipc_manager.cc
rename to src/queue_manager.cc
index 9690d6e9..aacc5c84 100644
--- a/src/ipc_manager.cc
+++ b/src/queue_manager.cc
@@ -1,36 +1,10 @@
-#include "ipc_manager.h"
+#include "queue_manager.h"
 
 #include "language_server_api.h"
 #include "query.h"
 
 #include <sstream>
 
-IpcManager* IpcManager::instance_ = nullptr;
-
-// static
-IpcManager* IpcManager::instance() {
-  return instance_;
-}
-
-// static
-void IpcManager::CreateInstance(MultiQueueWaiter* waiter) {
-  instance_ = new IpcManager(waiter);
-}
-
-// static
-void IpcManager::WriteStdout(IpcId id, lsBaseOutMessage& response) {
-  std::ostringstream sstream;
-  response.Write(sstream);
-
-  StdoutMessage out;
-  out.content = sstream.str();
-  out.id = id;
-  instance()->for_stdout.Enqueue(std::move(out));
-}
-
-IpcManager::IpcManager(MultiQueueWaiter* waiter)
-    : for_stdout(waiter), for_querydb(waiter) {}
-
 Index_Request::Index_Request(const std::string& path,
                              const std::vector<std::string>& args,
                              bool is_interactive,
@@ -66,8 +40,33 @@ Index_OnIndexed::Index_OnIndexed(IndexUpdate& update,
                                  PerformanceImportFile perf)
     : update(update), perf(perf) {}
 
+QueueManager* QueueManager::instance_ = nullptr;
+
+// static
+QueueManager* QueueManager::instance() {
+  return instance_;
+}
+
+// static
+void QueueManager::CreateInstance(MultiQueueWaiter* waiter) {
+  instance_ = new QueueManager(waiter);
+}
+
+// static
+void QueueManager::WriteStdout(IpcId id, lsBaseOutMessage& response) {
+  std::ostringstream sstream;
+  response.Write(sstream);
+
+  Stdout_Request out;
+  out.content = sstream.str();
+  out.id = id;
+  instance()->for_stdout.Enqueue(std::move(out));
+}
+
 QueueManager::QueueManager(MultiQueueWaiter* waiter)
-    : index_request(waiter),
+    : for_stdout(waiter),
+      for_querydb(waiter),
+      index_request(waiter),
       do_id_map(waiter),
       load_previous_index(waiter),
       on_id_mapped(waiter),
diff --git a/src/ipc_manager.h b/src/queue_manager.h
similarity index 70%
rename from src/ipc_manager.h
rename to src/queue_manager.h
index 775d757b..646cbb50 100644
--- a/src/ipc_manager.h
+++ b/src/queue_manager.h
@@ -7,28 +7,11 @@
 
 #include <memory>
 
-// TODO/FIXME: Merge IpcManager and QueueManager.
-
 struct lsBaseOutMessage;
 
-struct IpcManager {
-  struct StdoutMessage {
-    IpcId id;
-    std::string content;
-  };
-
-  ThreadedQueue<StdoutMessage> for_stdout;
-  ThreadedQueue<std::unique_ptr<BaseIpcMessage>> for_querydb;
-
-  static IpcManager* instance();
-  static void CreateInstance(MultiQueueWaiter* waiter);
-
-  static void WriteStdout(IpcId id, lsBaseOutMessage& response);
-
- private:
-  explicit IpcManager(MultiQueueWaiter* waiter);
-
-  static IpcManager* instance_;
+struct Stdout_Request {
+  IpcId id;
+  std::string content;
 };
 
 struct Index_Request {
@@ -87,18 +70,26 @@ struct Index_OnIndexed {
 };
 
 struct QueueManager {
-  using Index_RequestQueue = ThreadedQueue<Index_Request>;
-  using Index_DoIdMapQueue = ThreadedQueue<Index_DoIdMap>;
-  using Index_OnIdMappedQueue = ThreadedQueue<Index_OnIdMapped>;
-  using Index_OnIndexedQueue = ThreadedQueue<Index_OnIndexed>;
-
-  Index_RequestQueue index_request;
-  Index_DoIdMapQueue do_id_map;
-  Index_DoIdMapQueue load_previous_index;
-  Index_OnIdMappedQueue on_id_mapped;
-  Index_OnIndexedQueue on_indexed;
-
-  QueueManager(MultiQueueWaiter* waiter);
+  static QueueManager* instance();
+  static void CreateInstance(MultiQueueWaiter* waiter);
+  static void WriteStdout(IpcId id, lsBaseOutMessage& response);
 
   bool HasWork();
+
+  // Runs on stdout thread.
+  ThreadedQueue<Stdout_Request> for_stdout;
+  // Runs on querydb thread.
+  ThreadedQueue<std::unique_ptr<BaseIpcMessage>> for_querydb;
+
+  // Runs on indexer threads.
+  ThreadedQueue<Index_Request> index_request;
+  ThreadedQueue<Index_DoIdMap> do_id_map;
+  ThreadedQueue<Index_DoIdMap> load_previous_index;
+  ThreadedQueue<Index_OnIdMapped> on_id_mapped;
+  ThreadedQueue<Index_OnIndexed> on_indexed;
+
+ private:
+  explicit QueueManager(MultiQueueWaiter* waiter);
+
+  static QueueManager* instance_;
 };