diff --git a/examples/OpenCyphal-Blink/OpenCyphal-Blink.ino b/examples/OpenCyphal-Blink/OpenCyphal-Blink.ino
index 4a0a5bb4..8d7ac035 100644
--- a/examples/OpenCyphal-Blink/OpenCyphal-Blink.ino
+++ b/examples/OpenCyphal-Blink/OpenCyphal-Blink.ino
@@ -64,7 +64,7 @@ ArduinoMCP2515 mcp2515([]() { digitalWrite(MKRCAN_MCP2515_CS_PIN, LOW); },
 
 CyphalHeap<Node::DEFAULT_O1HEAP_SIZE> node_heap;
 Node node_hdl(node_heap.data(), node_heap.size());
-Publisher<Heartbeat_1_0<>> heartbeat_pub = node_hdl.create_publisher<Heartbeat_1_0<>>(Heartbeat_1_0<>::PORT_ID, CANARD_DEFAULT_TRANSFER_ID_TIMEOUT_USEC);
+Publisher<Heartbeat_1_0<>> heartbeat_pub = node_hdl.create_publisher<Heartbeat_1_0<>>(Heartbeat_1_0<>::PORT_ID, CANARD_DEFAULT_TRANSFER_ID_TIMEOUT_USEC, micros);
 
 Heartbeat_1_0<> hb_msg;
 
@@ -120,7 +120,7 @@ void loop()
 {
   /* Process all pending OpenCyphal actions.
    */
-  node_hdl.spinSome([] (CanardFrame const & frame) { return mcp2515.transmit(frame); });
+  node_hdl.spinSome([] (CanardFrame const & frame) { return mcp2515.transmit(frame); }, micros);
 
   /* Update the heartbeat object */
   hb_msg.data.uptime = millis() / 1000;
diff --git a/examples/OpenCyphal-GNSS-Node/OpenCyphal-GNSS-Node.ino b/examples/OpenCyphal-GNSS-Node/OpenCyphal-GNSS-Node.ino
index b54b7a6f..e1539ec5 100644
--- a/examples/OpenCyphal-GNSS-Node/OpenCyphal-GNSS-Node.ino
+++ b/examples/OpenCyphal-GNSS-Node/OpenCyphal-GNSS-Node.ino
@@ -147,7 +147,7 @@ void loop()
 {
   /* Process all pending OpenCyphal actions.
    */
-  node_hdl.spinSome([] (CanardFrame const & frame) { return mcp2515.transmit(frame); });
+  node_hdl.spinSome([] (CanardFrame const & frame) { return mcp2515.transmit(frame); }, micros);
 
   /* Handle actions common to all states.
    */
diff --git a/examples/OpenCyphal-Heartbeat-Publisher/OpenCyphal-Heartbeat-Publisher.ino b/examples/OpenCyphal-Heartbeat-Publisher/OpenCyphal-Heartbeat-Publisher.ino
index c8493bd6..0511f4c5 100644
--- a/examples/OpenCyphal-Heartbeat-Publisher/OpenCyphal-Heartbeat-Publisher.ino
+++ b/examples/OpenCyphal-Heartbeat-Publisher/OpenCyphal-Heartbeat-Publisher.ino
@@ -41,7 +41,7 @@ ArduinoMCP2515 mcp2515([]() { digitalWrite(MKRCAN_MCP2515_CS_PIN, LOW); },
 
 CyphalHeap<Node::DEFAULT_O1HEAP_SIZE> node_heap;
 Node node_hdl(node_heap.data(), node_heap.size());
-Publisher<Heartbeat_1_0<>> heartbeat_pub = node_hdl.create_publisher<Heartbeat_1_0<>>(Heartbeat_1_0<>::PORT_ID, CANARD_DEFAULT_TRANSFER_ID_TIMEOUT_USEC);
+Publisher<Heartbeat_1_0<>> heartbeat_pub = node_hdl.create_publisher<Heartbeat_1_0<>>(Heartbeat_1_0<>::PORT_ID, CANARD_DEFAULT_TRANSFER_ID_TIMEOUT_USEC, micros);
 
 Heartbeat_1_0<> hb_msg;
 
@@ -79,7 +79,7 @@ void loop()
 {
   /* Process all pending OpenCyphal actions.
    */
-  node_hdl.spinSome([] (CanardFrame const & frame) { return mcp2515.transmit(frame); });
+  node_hdl.spinSome([] (CanardFrame const & frame) { return mcp2515.transmit(frame); }, micros);
 
   /* Update the heartbeat object */
   hb_msg.data.uptime = millis() / 1000;
diff --git a/examples/OpenCyphal-Heartbeat-Subscribe/OpenCyphal-Heartbeat-Subscribe.ino b/examples/OpenCyphal-Heartbeat-Subscribe/OpenCyphal-Heartbeat-Subscribe.ino
index e0832eea..95593b54 100644
--- a/examples/OpenCyphal-Heartbeat-Subscribe/OpenCyphal-Heartbeat-Subscribe.ino
+++ b/examples/OpenCyphal-Heartbeat-Subscribe/OpenCyphal-Heartbeat-Subscribe.ino
@@ -80,7 +80,7 @@ void loop()
 {
   /* Process all pending OpenCyphal actions.
    */
-  node_hdl.spinSome([] (CanardFrame const & frame) { return mcp2515.transmit(frame); });
+  node_hdl.spinSome([] (CanardFrame const & frame) { return mcp2515.transmit(frame); }, micros);
 }
 
 /**************************************************************************************
diff --git a/examples/OpenCyphal-Service-Client/OpenCyphal-Service-Client.ino b/examples/OpenCyphal-Service-Client/OpenCyphal-Service-Client.ino
index be527dce..7272f68d 100644
--- a/examples/OpenCyphal-Service-Client/OpenCyphal-Service-Client.ino
+++ b/examples/OpenCyphal-Service-Client/OpenCyphal-Service-Client.ino
@@ -89,7 +89,7 @@ void loop()
 {
   /* Process all pending OpenCyphal actions.
    */
-  node_hdl.spinSome([] (CanardFrame const & frame) { return mcp2515.transmit(frame); });
+  node_hdl.spinSome([] (CanardFrame const & frame) { return mcp2515.transmit(frame); }, micros);
 }
 
 /**************************************************************************************
diff --git a/examples/OpenCyphal-Service-Server/OpenCyphal-Service-Server.ino b/examples/OpenCyphal-Service-Server/OpenCyphal-Service-Server.ino
index 1e61dc59..75830167 100644
--- a/examples/OpenCyphal-Service-Server/OpenCyphal-Service-Server.ino
+++ b/examples/OpenCyphal-Service-Server/OpenCyphal-Service-Server.ino
@@ -81,7 +81,7 @@ void loop()
 {
   /* Process all pending OpenCyphal actions.
    */
-  node_hdl.spinSome([] (CanardFrame const & frame) { return mcp2515.transmit(frame); });
+  node_hdl.spinSome([] (CanardFrame const & frame) { return mcp2515.transmit(frame); }, micros);
 }
 
 /**************************************************************************************
diff --git a/examples/OpenCyphal-ToF-Distance-Sensor-Node/OpenCyphal-ToF-Distance-Sensor-Node.ino b/examples/OpenCyphal-ToF-Distance-Sensor-Node/OpenCyphal-ToF-Distance-Sensor-Node.ino
index e7325ea5..0c371ff0 100644
--- a/examples/OpenCyphal-ToF-Distance-Sensor-Node/OpenCyphal-ToF-Distance-Sensor-Node.ino
+++ b/examples/OpenCyphal-ToF-Distance-Sensor-Node/OpenCyphal-ToF-Distance-Sensor-Node.ino
@@ -122,8 +122,8 @@ ArduinoMCP2515 mcp2515([]()
 
 CyphalHeap<Node::DEFAULT_O1HEAP_SIZE> node_heap;
 Node node_hdl(node_heap.data(), node_heap.size(), OPEN_CYPHAL_NODE_ID);
-Publisher<Heartbeat_1_0<>> heartbeat_pub = node_hdl.create_publisher<Heartbeat_1_0<>>(Heartbeat_1_0<>::PORT_ID, CANARD_DEFAULT_TRANSFER_ID_TIMEOUT_USEC);
-Publisher<DistanceMessageType> tof_pub = node_hdl.create_publisher<DistanceMessageType>(OPEN_CYPHAL_ID_DISTANCE_DATA, CANARD_DEFAULT_TRANSFER_ID_TIMEOUT_USEC);
+Publisher<Heartbeat_1_0<>> heartbeat_pub = node_hdl.create_publisher<Heartbeat_1_0<>>(Heartbeat_1_0<>::PORT_ID, CANARD_DEFAULT_TRANSFER_ID_TIMEOUT_USEC, micros);
+Publisher<DistanceMessageType> tof_pub = node_hdl.create_publisher<DistanceMessageType>(OPEN_CYPHAL_ID_DISTANCE_DATA, CANARD_DEFAULT_TRANSFER_ID_TIMEOUT_USEC, micros);
 
 OpenCyphalNodeData node_data = OPEN_CYPHAL_NODE_INITIAL_DATA;
 OpenCyphalNodeConfiguration node_config = OPEN_CYPHAL_NODE_INITIAL_CONFIGURATION;
@@ -243,7 +243,7 @@ void loop()
 {
   /* Process all pending OpenCyphal actions.
    */
-  node_hdl.spinSome([] (CanardFrame const & frame) { return mcp2515.transmit(frame); });
+  node_hdl.spinSome([] (CanardFrame const & frame) { return mcp2515.transmit(frame); }, micros);
 
   /* Handle actions common to all states.
    */
diff --git a/src/Node.cpp b/src/Node.cpp
index 55f8efcf..09f904ab 100644
--- a/src/Node.cpp
+++ b/src/Node.cpp
@@ -11,12 +11,6 @@
 
 #include "Node.hpp"
 
-/**************************************************************************************
- * FORWARD DECLARATION
- **************************************************************************************/
-
-extern "C" unsigned long micros();
-
 /**************************************************************************************
  * CTOR/DTOR
  **************************************************************************************/
@@ -40,10 +34,10 @@ Node::Node(uint8_t * heap_ptr,
  * PUBLIC MEMBER FUNCTIONS
  **************************************************************************************/
 
-void Node::spinSome(CanFrameTransmitFunc const tx_func)
+void Node::spinSome(CanFrameTransmitFunc const tx_func, TransferTimestampFunc const micros_func)
 {
   processRxQueue();
-  processTxQueue(tx_func);
+  processTxQueue(tx_func, micros_func);
 }
 
 void Node::onCanFrameReceived(CanardFrame const & frame, CanardMicrosecond const & rx_timestamp_us)
@@ -115,14 +109,14 @@ void Node::processRxQueue()
   }
 }
 
-void Node::processTxQueue(CanFrameTransmitFunc const tx_func)
+void Node::processTxQueue(CanFrameTransmitFunc const tx_func, TransferTimestampFunc const micros_func)
 {
   for(CanardTxQueueItem * tx_queue_item = const_cast<CanardTxQueueItem *>(canardTxPeek(&_canard_tx_queue));
       tx_queue_item != nullptr;
       tx_queue_item = const_cast<CanardTxQueueItem *>(canardTxPeek(&_canard_tx_queue)))
   {
     /* Discard the frame if the transmit deadline has expired. */
-    if (tx_queue_item->tx_deadline_usec > micros()) {
+    if (tx_queue_item->tx_deadline_usec > micros_func()) {
       _canard_hdl.memory_free(&_canard_hdl, canardTxPop(&_canard_tx_queue, tx_queue_item));
       continue;
     }
diff --git a/src/Node.hpp b/src/Node.hpp
index e1f55e32..296ed70b 100644
--- a/src/Node.hpp
+++ b/src/Node.hpp
@@ -40,6 +40,7 @@
 class Node;
 typedef std::function<void(CanardRxTransfer const &, Node &)> OnTransferReceivedFunc;
 typedef std::function<bool(CanardFrame const &)> CanFrameTransmitFunc;
+typedef std::function<CanardMicrosecond(void)> TransferTimestampFunc;
 
 template <size_t SIZE>
 struct alignas(O1HEAP_ALIGNMENT) CyphalHeap final : public std::array<uint8_t, SIZE> {};
@@ -76,12 +77,15 @@ class Node
   inline void setNodeId(CanardNodeID const node_id) { _canard_hdl.node_id = node_id; }
   inline CanardNodeID getNodeId() const { return _canard_hdl.node_id; }
 
-  template <typename T> Publisher<T> create_publisher(CanardPortID const port_id, CanardMicrosecond const tx_timeout_usec);
+  template <typename T>
+  Publisher<T> create_publisher(CanardPortID const port_id,
+                                CanardMicrosecond const tx_timeout_usec,
+                                std::function<CanardMicrosecond(void)> const micros_func);
 
   /* Must be called from the application to process
    * all received CAN frames.
    */
-  void spinSome(CanFrameTransmitFunc const tx_func);
+  void spinSome(CanFrameTransmitFunc const tx_func, TransferTimestampFunc const micros_func);
   /* Must be called from the application upon the
    * reception of a can frame.
    */
@@ -115,7 +119,7 @@ class Node
   static void   o1heap_free    (CanardInstance * const ins, void * const pointer);
 
   void processRxQueue();
-  void processTxQueue(CanFrameTransmitFunc const tx_func);
+  void processTxQueue(CanFrameTransmitFunc const tx_func, TransferTimestampFunc const micros_func);
 
   CanardTransferID getNextTransferId(CanardPortID const port_id);
   bool             subscribe        (CanardTransferKind const transfer_kind, CanardPortID const port_id, size_t const payload_size_max, OnTransferReceivedFunc func);
diff --git a/src/Node.ipp b/src/Node.ipp
index c06bd241..87bdca22 100644
--- a/src/Node.ipp
+++ b/src/Node.ipp
@@ -10,9 +10,11 @@
  **************************************************************************************/
 
 template <typename T>
-Publisher<T> Node::create_publisher(CanardPortID const port_id, CanardMicrosecond const tx_timeout_usec)
+Publisher<T> Node::create_publisher(CanardPortID const port_id,
+                                    CanardMicrosecond const tx_timeout_usec,
+                                    std::function<CanardMicrosecond(void)> const micros_func)
 {
-  return std::make_shared<impl::Publisher<T>>(_canard_hdl, _canard_tx_queue, port_id, tx_timeout_usec);
+  return std::make_shared<impl::Publisher<T>>(_canard_hdl, _canard_tx_queue, port_id, tx_timeout_usec, micros_func);
 }
 
 template <typename T>
diff --git a/src/Publisher.hpp b/src/Publisher.hpp
index 85295c7f..15e05224 100644
--- a/src/Publisher.hpp
+++ b/src/Publisher.hpp
@@ -29,11 +29,12 @@ template <typename T>
 class Publisher
 {
 public:
-  Publisher(CanardInstance & canard_hdl, CanardTxQueue & canard_tx_queue, CanardPortID const port_id, CanardMicrosecond const tx_timeout_usec)
+  Publisher(CanardInstance & canard_hdl, CanardTxQueue & canard_tx_queue, CanardPortID const port_id, CanardMicrosecond const tx_timeout_usec, std::function<CanardMicrosecond(void)> const micros_func)
   : _canard_hdl{canard_hdl}
   , _canard_tx_queue{canard_tx_queue}
   , _port_id{port_id}
   , _tx_timeout_usec{tx_timeout_usec}
+  , _micros_func{micros_func}
   , _transfer_id{0}
   { }
 
@@ -44,6 +45,7 @@ class Publisher
   CanardTxQueue & _canard_tx_queue;
   CanardPortID const _port_id;
   CanardMicrosecond const _tx_timeout_usec;
+  std::function<CanardMicrosecond(void)> const _micros_func;
   CanardTransferID _transfer_id;
 };
 
diff --git a/src/Publisher.ipp b/src/Publisher.ipp
index 36a08430..b2ec799a 100644
--- a/src/Publisher.ipp
+++ b/src/Publisher.ipp
@@ -18,12 +18,6 @@
 namespace impl
 {
 
-/**************************************************************************************
- * FORWARD DECLARATION
- **************************************************************************************/
-
-extern "C" unsigned long micros();
-
 /**************************************************************************************
  * PUBLIC MEMBER FUNCTIONS
  **************************************************************************************/
@@ -47,7 +41,7 @@ bool Publisher<T>::publish(T const & msg)
   /* Serialize transfer into a series of CAN frames */
   int32_t result = canardTxPush(&_canard_tx_queue,
                                 &_canard_hdl,
-                                micros() + _tx_timeout_usec,
+                                _micros_func() + _tx_timeout_usec,
                                 &transfer_metadata,
                                 payload_buf_size,
                                 payload_buf.data());