diff --git a/src/internal/mana_analysis.h b/src/internal/mana_analysis.h
index 4f216e6..096ff98 100644
--- a/src/internal/mana_analysis.h
+++ b/src/internal/mana_analysis.h
@@ -74,8 +74,8 @@ auto_match_modules(const mvlc::CrateConfig &crateConfig, const nlohmann::json &m
                     jModule = jModule_;
                     jModule["name"] = fmt::format("{}.{}", event.getName(), module_.name);
                     for (auto &jSource: jModule["data_sources"])
-                        jSource["name"] =
-                            fmt::format("{}.{}.{}", event.getName(), module_.name, jSource["name"].get<std::string>());
+                        jSource["name"] = fmt::format("{}.{}.{}", event.getName(), module_.name,
+                                                      jSource["name"].get<std::string>());
                     break;
                 }
             }
@@ -196,15 +196,13 @@ inline nlohmann::json make_run_descriptor(const RunInfo &runInfo)
 
 inline ModuleDataStage make_module_data_stage(const std::string &runName, mana::Arena &&arena,
                                               const mvlc::CrateConfig &crateConfig,
-                                              nlohmann::json moduleDb, IManaSink *sink,
-                                              void *sinkContext)
+                                              nlohmann::json moduleDb, IManaSink *sink)
 {
     ModuleDataStage result;
 
     result.arena = std::move(arena);
     result.crateConfig = crateConfig;
     result.sink = sink;
-    result.sinkContext = sinkContext;
     result.moduleInfo = auto_match_modules(crateConfig, moduleDb);
     result.runInfo = make_run_info(runName, crateConfig, result.moduleInfo);
     allocate_outputs(result.arena, result.runInfo);
diff --git a/src/internal/mana_nng.hpp b/src/internal/mana_nng.hpp
index 9d99630..e176228 100644
--- a/src/internal/mana_nng.hpp
+++ b/src/internal/mana_nng.hpp
@@ -13,6 +13,7 @@ struct MessageHeader
 {
     enum MessageType
     {
+        Invalid = 0,
         BeginRun = 42,
         EndRun,
         EventData,
diff --git a/src/tools/mana_auto_replay.cc b/src/tools/mana_auto_replay.cc
index e89d300..0c6962a 100644
--- a/src/tools/mana_auto_replay.cc
+++ b/src/tools/mana_auto_replay.cc
@@ -139,13 +139,14 @@ std::optional<ParserContext> make_parser_context(const mvlc::CrateConfig &crateC
     }
 }
 
-struct ProcessingStrategy
+struct ReplayStrategy
 {
-    virtual ~ProcessingStrategy() = default;
+    virtual ~ReplayStrategy() = default;
     virtual void run(ListfileContext &listfileContext, ParserContext &parserContext) = 0;
 };
 
-struct SingleThreadedStrategy: public ProcessingStrategy
+// Reading buffers from file and parsing them is done in the same thread.
+struct SingleThreadedStrategy: public ReplayStrategy
 {
     inline static size_t process_one_buffer(size_t bufferNumber, ListfileContext &listfileContext,
                                             ParserContext &parserContext)
@@ -204,7 +205,8 @@ struct SingleThreadedStrategy: public ProcessingStrategy
     }
 };
 
-struct NngPairStrategy: public ProcessingStrategy
+// An extra file reader thread is spawned. Parsing is done in the thread calling run()po
+struct NngPairStrategy: public ReplayStrategy
 {
     struct SocketCounters
     {
@@ -373,12 +375,12 @@ struct NngPairStrategy: public ProcessingStrategy
 void usage(const char *self)
 {
     std::cout << fmt::format(
-        "usage: {} [--plugin=<plugin.so>] [--processing-strategy=<name>] <zipfile>\n", self);
+        "usage: {} [--plugin=<plugin.so>] [--replay-strategy=<name>] <zipfile>\n", self);
     std::cout
         << "  --plugin=<plugin.so>            Load a plugin to process the data. Default is a "
            "simple counting plugin.\n"
-        << "  --processing-strategy=<name>    Use a specific processing strategy. "
-           "Available: 'single-threaded', 'nng-pair'. Default: 'nng-pair'\n"
+        << "  --replay-strategy=<name>        Use a specific replay strategy. "
+           "Available: 'single-threaded', 'multi-threaded'. Default: 'multi-threaded'\n"
         << "  --log-level=<level>             One of 'trace', 'debug', 'info', 'warn', 'error', "
            "'off'.\n";
 }
@@ -388,7 +390,8 @@ int main(int argc, char *argv[])
     auto f = cmrc::mnode::resources::get_filesystem().open("data/vme_module_data_sources.json");
     const auto jModuleDataSources = nlohmann::json::parse(f.begin(), f.end());
 
-    argh::parser parser({"-h", "--help", "--plugin", "--processing-strategy", "--log-level"});
+    argh::parser parser(
+        {"-h", "--help", "--plugin", "--replay-strategy", "--no-buffering ", "--log-level"});
     parser.parse(argc, argv);
 
     auto filename = parser[1];
@@ -459,26 +462,26 @@ int main(int argc, char *argv[])
 
     auto manaSink = std::make_unique<mana::ManaSinkPerfProxy>(destSink.get());
 
-    std::string strategyName = "nng-pair";
+    std::string strategyName = "multi-threaded";
 
-    if (parser("--processing-strategy"))
-        strategyName = parser("--processing-strategy").str();
+    if (parser("--replay-strategy"))
+        strategyName = parser("--replay-strategy").str();
 
-    std::unique_ptr<ProcessingStrategy> processingStrategy;
+    std::unique_ptr<ReplayStrategy> replayStrategy;
 
-    if (strategyName == "nng-pair")
-        processingStrategy = std::make_unique<NngPairStrategy>("inproc://mana_module_data_stage");
+    if (strategyName == "multi-threaded")
+        replayStrategy = std::make_unique<NngPairStrategy>("inproc://mana_mvlc_parsing_stage");
     else if (strategyName == "single-threaded")
-        processingStrategy = std::make_unique<SingleThreadedStrategy>();
+        replayStrategy = std::make_unique<SingleThreadedStrategy>();
     else
     {
-        std::cerr << fmt::format("Error: unknown processing strategy '{}'\n", strategyName);
+        std::cerr << fmt::format("Error: unknown replay strategy '{}'\n", strategyName);
         usage(argv[0]);
         return 1;
     }
 
     auto mana = mana::make_module_data_stage(filename, mana::Arena(), listfileContext->crateConfig,
-                                             jModuleDataSources, manaSink.get(), nullptr);
+                                             jModuleDataSources, destSink.get());
 
     auto event_data = [](void *ctx_, int crateIndex, int eventIndex,
                          const mvlc::readout_parser::ModuleData *moduleDataList,
@@ -505,13 +508,22 @@ int main(int argc, char *argv[])
     // make the analysis instance available to the parser callbacks
     parserContext->parser.userContext = &mana;
 
-    mana.sink->init(0, nullptr);
-    mana.sink->begin_run(mana.runDescriptor.dump().c_str());
+    auto run_replay = [&]
+    {
+        manaSink->init(0, nullptr);
+        manaSink->begin_run(mana.runDescriptor.dump().c_str());
 
-    processingStrategy->run(*listfileContext, *parserContext);
+        replayStrategy->run(*listfileContext, *parserContext);
 
-    mana.sink->end_run(mana.runDescriptor.dump().c_str());
-    mana.sink->shutdown();
+        manaSink->end_run(mana.runDescriptor.dump().c_str());
+        manaSink->shutdown();
+    };
+
+    // if (parser["--no-buffering"])
+    {
+        mana.sink = manaSink.get();
+        run_replay();
+    }
 
     auto perf = manaSink->perf();
     {