diff --git a/compiler/include/concretelang/Runtime/context.h b/compiler/include/concretelang/Runtime/context.h
index 9274dc1e3..1bd4edf9d 100644
--- a/compiler/include/concretelang/Runtime/context.h
+++ b/compiler/include/concretelang/Runtime/context.h
@@ -8,7 +8,7 @@
 
 #include <map>
 #include <mutex>
-#include <string>
+#include <pthread.h>
 
 extern "C" {
 #include "concrete-ffi.h"
@@ -20,53 +20,23 @@ namespace concretelang {
 typedef struct RuntimeContext {
   LweKeyswitchKey_u64 *ksk;
   LweBootstrapKey_u64 *bsk;
-#ifdef CONCRETELANG_PARALLEL_EXECUTION_ENABLED
-  std::map<std::string, Engine *> engines;
+  std::map<pthread_t, Engine *> engines;
   std::mutex engines_map_guard;
-#else
-  Engine *engine;
-#endif
 
-  RuntimeContext()
-#ifndef CONCRETELANG_PARALLEL_EXECUTION_ENABLED
-      : engine(nullptr)
-#endif
-  {
-  }
+  RuntimeContext() {}
   // Ensure that the engines map is not copied
-  RuntimeContext(const RuntimeContext &ctx)
-      : ksk(ctx.ksk), bsk(ctx.bsk)
-#ifndef CONCRETELANG_PARALLEL_EXECUTION_ENABLED
-        ,
-        engine(nullptr)
-#endif
-  {
-  }
+  RuntimeContext(const RuntimeContext &ctx) : ksk(ctx.ksk), bsk(ctx.bsk) {}
   RuntimeContext(const RuntimeContext &&other)
-      : ksk(other.ksk), bsk(other.bsk)
-#ifndef CONCRETELANG_PARALLEL_EXECUTION_ENABLED
-        ,
-        engine(nullptr)
-#endif
-  {
-  }
+      : ksk(other.ksk), bsk(other.bsk) {}
   ~RuntimeContext() {
-#ifdef CONCRETELANG_PARALLEL_EXECUTION_ENABLED
     for (const auto &key : engines) {
       free_engine(key.second);
     }
-#else
-    if (engine != nullptr)
-      free_engine(engine);
-#endif
   }
 
   RuntimeContext &operator=(const RuntimeContext &rhs) {
     ksk = rhs.ksk;
     bsk = rhs.bsk;
-#ifndef CONCRETELANG_PARALLEL_EXECUTION_ENABLED
-    engine = nullptr;
-#endif
     return *this;
   }
 } RuntimeContext;
diff --git a/compiler/lib/Runtime/CMakeLists.txt b/compiler/lib/Runtime/CMakeLists.txt
index 8c95b67e7..286677bce 100644
--- a/compiler/lib/Runtime/CMakeLists.txt
+++ b/compiler/lib/Runtime/CMakeLists.txt
@@ -4,6 +4,10 @@ add_library(ConcretelangRuntime SHARED
     dfr_terminate.cpp
 )
 
+if (NOT ${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
+  link_libraries(-Wl,--no-as-needed omp)
+endif()
+
 if(CONCRETELANG_PARALLEL_EXECUTION_ENABLED)
   add_library(DFRuntime SHARED DFRuntime.cpp)
   target_link_libraries(DFRuntime PUBLIC pthread m dl HPX::hpx HPX::iostreams_component -rdynamic)
@@ -21,9 +25,9 @@ if(CONCRETELANG_PARALLEL_EXECUTION_ENABLED)
     -Wl,--no-as-needed
     DFRuntime
     omp
-  )
+    )
 else()
-  target_link_libraries(ConcretelangRuntime Concrete pthread m dl $<TARGET_OBJECTS:mlir_c_runner_utils>)
+  target_link_libraries(ConcretelangRuntime Concrete pthread m dl $<TARGET_OBJECTS:mlir_c_runner_utils> omp)
 endif()
 
 install(TARGETS ConcretelangRuntime omp EXPORT ConcretelangRuntime)
diff --git a/compiler/lib/Runtime/context.cpp b/compiler/lib/Runtime/context.cpp
index e51df477b..a524a140a 100644
--- a/compiler/lib/Runtime/context.cpp
+++ b/compiler/lib/Runtime/context.cpp
@@ -7,10 +7,6 @@
 #include <concretelang/Runtime/context.h>
 #include <stdio.h>
 
-#ifdef CONCRETELANG_PARALLEL_EXECUTION_ENABLED
-#include <hpx/include/runtime.hpp>
-#endif
-
 LweKeyswitchKey_u64 *
 get_keyswitch_key_u64(mlir::concretelang::RuntimeContext *context) {
   return context->ksk;
@@ -23,20 +19,15 @@ get_bootstrap_key_u64(mlir::concretelang::RuntimeContext *context) {
 
 // Instantiate one engine per thread on demand
 Engine *get_engine(mlir::concretelang::RuntimeContext *context) {
-#ifdef CONCRETELANG_PARALLEL_EXECUTION_ENABLED
-  std::string threadName = hpx::get_thread_name();
+  pthread_t threadId = pthread_self();
   std::lock_guard<std::mutex> guard(context->engines_map_guard);
-  auto engineIt = context->engines.find(threadName);
+  auto engineIt = context->engines.find(threadId);
   if (engineIt == context->engines.end()) {
     engineIt =
         context->engines
-            .insert(std::pair<std::string, Engine *>(threadName, new_engine()))
+            .insert(std::pair<pthread_t, Engine *>(threadId, new_engine()))
             .first;
   }
   assert(engineIt->second && "No engine available in context");
   return engineIt->second;
-#else
-  return (context->engine == nullptr) ? context->engine = new_engine()
-                                      : context->engine;
-#endif
 }