diff --git a/.github/workflows/cmake-single-platform.yml b/.github/workflows/cmake-single-platform.yml
index d3144c1..93afeb4 100644
--- a/.github/workflows/cmake-single-platform.yml
+++ b/.github/workflows/cmake-single-platform.yml
@@ -11,6 +11,8 @@ on:
 env:
   # Customize the CMake build type here (Release, Debug, RelWithDebInfo, etc.)
   BUILD_TYPE: Release
+  CC: gcc-13
+  CXX: g++-13
 
 jobs:
   build:
diff --git a/README.md b/README.md
index d81a014..3e656b7 100644
--- a/README.md
+++ b/README.md
@@ -22,7 +22,8 @@
   - [Iterate through tasks](#iterate-through-tasks)
   - [Append attributes to tasks and modify the task attribute values](#append-attributes-to-tasks-and-modify-the-task-attribute-values)
   - [Specify the default offloading strategy](#specify-the-default-offloading-strategy)
-  - [Offloading your first set of tasks using the worst-fit decision engine](#offloading-your-first-set-of-tasks-using-the-worst-fit-decision-engine)
+  - [Asynchronously offload your first set of tasks using the worst-fit decision engine with callbacks](#asynchronously-offload-your-first-set-of-tasks-using-the-worst-fit-decision-engine-with-callbacks)
+  - [Asynchronously offload your first set of tasks using the worst-fit decision engine with coroutines](#asynchronously-offload-your-first-set-of-tasks-using-the-worst-fit-decision-engine-with-coroutines)
 
 ## Prerequisites
 **Libraries**
@@ -367,7 +368,78 @@ When your program runs, the decision engine will automatically gather resource i
 [+0.00000000s] █ The decision engine received resource information from edge server(10.1.2.5).
 ```
 
-### Offloading your first set of tasks using the worst-fit decision engine 
+### Asynchronously offload your first set of tasks using the worst-fit decision engine with callbacks
+```cpp
+#include <okec/okec.hpp>
+
+namespace olog =  okec::log;
+
+
+void generate_task(okec::task& t, int number, std::string const& group)
+{
+    for (auto i = number; i-- > 0;)
+    {
+        t.emplace_back({
+            { "task_id", okec::task::get_unique_id() },
+            { "group", group },
+            { "cpu", okec::rand_range(0.2, 1.2).to_string() },
+            { "deadline", okec::rand_range(1, 5).to_string() },
+        });
+    }
+}
+
+
+int main()
+{
+    olog::set_level(olog::level::all);
+    okec::simulator sim;
+
+    // Create 1 base station
+    okec::base_station_container base_stations(sim, 1);
+    // Create 5 edge servers
+    okec::edge_device_container edge_servers(sim, 5);
+    // Create 2 user devices
+    okec::client_device_container user_devices(sim, 2);
+
+    // Connect the base stations and edge servers
+    base_stations.connect_device(edge_servers);
+
+    // Set the network model for every device
+    okec::multiple_and_single_LAN_WLAN_network_model model;
+    okec::network_initializer(model, user_devices, base_stations.get(0));
+
+    // Initialize the resources for each edge server.
+    okec::resource_container resources(edge_servers.size());
+    resources.initialize([](auto res) {
+        res->attribute("cpu", okec::rand_range(2.1, 2.2).to_string());
+    });
+
+    // Install each resource on each edge server.
+    edge_servers.install_resources(resources);
+
+    // Specify the default offloading strategy
+    auto decision_engine = std::make_shared<okec::worst_fit_decision_engine>(&user_devices, &base_stations);
+    decision_engine->initialize();
+
+
+    // Offload tasks
+    okec::task t;
+    generate_task(t, 5, "1st");
+    auto user1 = user_devices.get_device(0);
+    user1->async_send(std::move(t));
+    user1->async_read([](auto resp) {
+        olog::success("received response.");
+
+        okec::print("{:r}", resp);
+    });
+
+
+    // Run the simulator
+    sim.run();
+}
+```
+
+### Asynchronously offload your first set of tasks using the worst-fit decision engine with coroutines 
 ```cpp
 #include <okec/okec.hpp>
 
@@ -386,8 +458,7 @@ void generate_task(okec::task& t, int number, std::string const& group)
     }
 }
 
-okec::awaitable
-offloading(std::shared_ptr<okec::client_device> user, okec::task t) {
+okec::awaitable offloading(auto user, okec::task t) {
     olog::debug("offloading begin");
 
     co_await user->async_send(std::move(t));
diff --git a/examples/src/wf_async.cc b/examples/src/wf_async.cc
index cf73de8..cba40ad 100644
--- a/examples/src/wf_async.cc
+++ b/examples/src/wf_async.cc
@@ -25,8 +25,7 @@ void my_monitor(std::string_view address, std::string_view attr, std::string_vie
     file << okec::format("At time {:.2f}s,{},{},{}\n", okec::now::seconds(), address, old_val, new_val);
 }
 
-okec::awaitable
-offloading(std::shared_ptr<okec::client_device> user, okec::task t) {
+okec::awaitable offloading(auto user, okec::task t) {
     log::debug("offloading begin");
     
     co_await user->async_send(std::move(t));