diff --git a/compiler/lib/Runtime/DFRuntime.cpp b/compiler/lib/Runtime/DFRuntime.cpp
index 133f63280..569ab2500 100644
--- a/compiler/lib/Runtime/DFRuntime.cpp
+++ b/compiler/lib/Runtime/DFRuntime.cpp
@@ -743,8 +743,6 @@ void _dfr_set_required(bool is_required) {
   mlir::concretelang::dfr::dfr_required_p = is_required;
   if (mlir::concretelang::dfr::dfr_required_p) {
     _dfr_try_initialize();
-    mlir::concretelang::dfr::is_root_node_p =
-        (hpx::find_here() == hpx::find_root_locality());
   }
 }
 void _dfr_set_jit(bool is_jit) { mlir::concretelang::dfr::is_jit_p = is_jit; }
@@ -782,7 +780,7 @@ static inline void _dfr_stop_impl() {
 static inline void _dfr_start_impl(int argc, char *argv[]) {
   mlir::concretelang::dfr::dl_handle = dlopen(nullptr, RTLD_NOW);
   if (argc == 0) {
-    unsigned long nCores, nOMPThreads, nHPXThreads;
+    int nCores, nOMPThreads, nHPXThreads;
     hwloc_topology_t topology;
     hwloc_topology_init(&topology);
     hwloc_topology_set_all_types_filter(topology, HWLOC_TYPE_FILTER_KEEP_NONE);
@@ -792,33 +790,48 @@ static inline void _dfr_start_impl(int argc, char *argv[]) {
     nCores = hwloc_get_nbobjs_by_type(topology, HWLOC_OBJ_CORE);
     if (nCores < 1)
       nCores = 1;
-    nOMPThreads = 1;
+
     char *env = getenv("OMP_NUM_THREADS");
-    if (env != nullptr) {
+    if (env != nullptr)
       nOMPThreads = strtoul(env, NULL, 10);
-      if (nOMPThreads == 0)
-        nOMPThreads = 1;
-      if (nOMPThreads >= nCores)
-        nOMPThreads = nCores;
-    }
-    std::string numOMPThreads = std::to_string(nOMPThreads);
-    setenv("OMP_NUM_THREADS", numOMPThreads.c_str(), 0);
-    nHPXThreads = nCores + 1 - nOMPThreads;
+    else
+      nOMPThreads = nCores;
+
     env = getenv("DFR_NUM_THREADS");
     if (env != nullptr)
       nHPXThreads = strtoul(env, NULL, 10);
-    nHPXThreads = (nHPXThreads) ? nHPXThreads : 1;
-    std::string numHPXThreads = std::to_string(nHPXThreads);
-    char *_argv[3] = {const_cast<char *>("__dummy_dfr_HPX_program_name__"),
-                      const_cast<char *>("--hpx:threads"),
-                      const_cast<char *>(numHPXThreads.c_str())};
-    int _argc = 3;
-    hpx::start(nullptr, _argc, _argv);
+    else
+      nHPXThreads = nCores + 1 - nOMPThreads;
+    if (nHPXThreads < 1)
+      nHPXThreads = 1;
+
+    env = getenv("HPX_CONFIG_FILE");
+    if (env != nullptr) {
+      int _argc = 3;
+      char *_argv[3] = {const_cast<char *>("__dummy_dfr_HPX_program_name__"),
+                        const_cast<char *>("--hpx:config"),
+                        const_cast<char *>(env)};
+      hpx::start(nullptr, _argc, _argv);
+    } else {
+      std::string numHPXThreads = std::to_string(nHPXThreads);
+      int _argc = 7;
+      char *_argv[7] = {
+          const_cast<char *>("__dummy_dfr_HPX_program_name__"),
+          const_cast<char *>("--hpx:threads"),
+          const_cast<char *>(numHPXThreads.c_str()),
+          const_cast<char *>("--hpx:ini=hpx.stacks.small_size=0x8000000"),
+          const_cast<char *>("--hpx:ini=hpx.stacks.medium_size=0x10000000"),
+          const_cast<char *>("--hpx:ini=hpx.stacks.large_size=0x20000000"),
+          const_cast<char *>("--hpx:ini=hpx.stacks.huge_size=0x40000000")};
+      hpx::start(nullptr, _argc, _argv);
+    }
   } else {
     hpx::start(nullptr, argc, argv);
   }
 
-  // Instantiate on each node
+  // Instantiate and initialise on each node
+  mlir::concretelang::dfr::is_root_node_p =
+      (hpx::find_here() == hpx::find_root_locality());
   new mlir::concretelang::dfr::KeyManager<LweBootstrapKey_u64>();
   new mlir::concretelang::dfr::KeyManager<LweKeyswitchKey_u64>();
   new mlir::concretelang::dfr::WorkFunctionRegistry();