diff --git a/src/Lean/Server/Watchdog.lean b/src/Lean/Server/Watchdog.lean
index d8ca093930..14ff2ed8ec 100644
--- a/src/Lean/Server/Watchdog.lean
+++ b/src/Lean/Server/Watchdog.lean
@@ -153,6 +153,7 @@ section ServerM
     hIn            : FS.Stream
     hOut           : FS.Stream
     hLog           : FS.Stream
+    args           : List String
     fileWorkersRef : IO.Ref FileWorkerMap
     -- We store these to pass them to workers.
     initParams     : InitializeParams
@@ -213,7 +214,7 @@ section ServerM
       toStdioConfig := workerCfg
       cmd           := st.workerPath
       -- append file and imports for Nix support; ignored otherwise
-      args          := #["--worker"] ++ (Lean.Elab.headerToImports headerAst).toArray.map (toString ·.module)
+      args          := #["--worker"] ++ (Lean.Elab.headerToImports headerAst).toArray.map (toString ·.module) ++ st.args.toArray
     }
     let pendingRequestsRef ← IO.mkRef (RBMap.empty : PendingRequestMap)
     -- The task will never access itself, so this is fine
@@ -449,7 +450,7 @@ def initAndRunWatchdogAux : ServerM Unit := do
     shutdown
     throw err
 
-def initAndRunWatchdog (i o e : FS.Stream) : IO Unit := do
+def initAndRunWatchdog (args : List String) (i o e : FS.Stream) : IO Unit := do
   let workerPath ← match (←IO.getEnv "LEAN_WORKER_PATH") with
     | none   => IO.appPath
     | some p => p
@@ -473,6 +474,7 @@ def initAndRunWatchdog (i o e : FS.Stream) : IO Unit := do
     hIn            := i
     hOut           := o
     hLog           := e
+    args           := args
     fileWorkersRef := fileWorkersRef
     initParams     := initRequest.param
     workerPath     := workerPath
@@ -480,12 +482,12 @@ def initAndRunWatchdog (i o e : FS.Stream) : IO Unit := do
   }
 
 @[export lean_server_watchdog_main]
-def watchdogMain : IO UInt32 := do
+def watchdogMain (args : List String) : IO UInt32 := do
   let i ← IO.getStdin
   let o ← IO.getStdout
   let e ← IO.getStderr
   try
-    initAndRunWatchdog i o e
+    initAndRunWatchdog args i o e
     return 0
   catch err =>
     e.putStrLn s!"Watchdog error: {err}"
diff --git a/src/shell/lean.cpp b/src/shell/lean.cpp
index 7eb4659fd1..f014faaaf8 100644
--- a/src/shell/lean.cpp
+++ b/src/shell/lean.cpp
@@ -334,10 +334,11 @@ uint32_t run_server_worker() {
     return get_io_scalar_result<uint32_t>(lean_server_worker_main(io_mk_world()));
 }
 
-/* def watchdogMain : IO Uint32 */
-extern "C" object* lean_server_watchdog_main(object* w);
-uint32_t run_server_watchdog() {
-    return get_io_scalar_result<uint32_t>(lean_server_watchdog_main(io_mk_world()));
+/* def watchdogMain (args : List String) : IO Uint32 */
+extern "C" object* lean_server_watchdog_main(object* args, object* w);
+uint32_t run_server_watchdog(buffer<string_ref> const & args) {
+    list_ref<string_ref> arglist = to_list_ref(args);
+    return get_io_scalar_result<uint32_t>(lean_server_watchdog_main(arglist.to_obj_arg(), io_mk_world()));
 }
 
 extern "C" object* lean_init_search_path(object* opt_path, object* w);
@@ -434,6 +435,8 @@ int main(int argc, char ** argv) {
     std::string native_output;
     optional<std::string> c_output;
     optional<std::string> root_dir;
+    buffer<string_ref> forwarded_args;
+
     while (true) {
         int c = getopt_long(argc, argv, g_opt_str, g_long_options, NULL);
         if (c == -1)
@@ -444,6 +447,7 @@ int main(int argc, char ** argv) {
                 break;
             case 'j':
                 num_threads = static_cast<unsigned>(atoi(optarg));
+                forwarded_args.push_back(string_ref("-j" + std::string(optarg)));
                 break;
             case 'v':
                 display_header(std::cout);
@@ -480,6 +484,7 @@ int main(int argc, char ** argv) {
                 break;
             case 'T':
                 check_optarg("T");
+                forwarded_args.push_back(string_ref("-T" + std::string(optarg)));
                 opts = opts.update(get_timeout_opt_name(), static_cast<unsigned>(atoi(optarg)));
                 break;
             case 't':
@@ -555,7 +560,7 @@ int main(int argc, char ** argv) {
 
     try {
         if (run_server == 1)
-            return run_server_watchdog();
+            return run_server_watchdog(forwarded_args);
         else if (run_server == 2)
             return run_server_worker();