diff --git a/include/libcamera/base/event_notifier.h b/include/libcamera/base/event_notifier.h
index 5055ccbf2..f7722a32e 100644
--- a/include/libcamera/base/event_notifier.h
+++ b/include/libcamera/base/event_notifier.h
@@ -34,7 +34,7 @@ public:
 	bool enabled() const { return enabled_; }
 	void setEnabled(bool enable);
 
-	Signal<EventNotifier *> activated;
+	Signal<> activated;
 
 protected:
 	void message(Message *msg) override;
diff --git a/include/libcamera/base/thread.h b/include/libcamera/base/thread.h
index 762beab2a..e0ca0aeaa 100644
--- a/include/libcamera/base/thread.h
+++ b/include/libcamera/base/thread.h
@@ -41,7 +41,7 @@ public:
 
 	bool isRunning();
 
-	Signal<Thread *> finished;
+	Signal<> finished;
 
 	static Thread *current();
 	static pid_t currentId();
diff --git a/include/libcamera/base/timer.h b/include/libcamera/base/timer.h
index 798821611..44876a85d 100644
--- a/include/libcamera/base/timer.h
+++ b/include/libcamera/base/timer.h
@@ -33,7 +33,7 @@ public:
 
 	std::chrono::steady_clock::time_point deadline() const { return deadline_; }
 
-	Signal<Timer *> timeout;
+	Signal<> timeout;
 
 protected:
 	void message(Message *msg) override;
diff --git a/include/libcamera/camera.h b/include/libcamera/camera.h
index 05cdab724..601ee46e4 100644
--- a/include/libcamera/camera.h
+++ b/include/libcamera/camera.h
@@ -86,7 +86,7 @@ public:
 
 	Signal<Request *, FrameBuffer *> bufferCompleted;
 	Signal<Request *> requestCompleted;
-	Signal<Camera *> disconnected;
+	Signal<> disconnected;
 
 	int acquire();
 	int release();
diff --git a/include/libcamera/internal/device_enumerator_udev.h b/include/libcamera/internal/device_enumerator_udev.h
index 58e64a297..c03529808 100644
--- a/include/libcamera/internal/device_enumerator_udev.h
+++ b/include/libcamera/internal/device_enumerator_udev.h
@@ -59,7 +59,7 @@ private:
 	std::string lookupDeviceNode(dev_t devnum);
 
 	int addV4L2Device(dev_t devnum);
-	void udevNotify(EventNotifier *notifier);
+	void udevNotify();
 
 	struct udev *udev_;
 	struct udev_monitor *monitor_;
diff --git a/include/libcamera/internal/ipc_pipe_unixsocket.h b/include/libcamera/internal/ipc_pipe_unixsocket.h
index 4ffdddcc7..ad2927fed 100644
--- a/include/libcamera/internal/ipc_pipe_unixsocket.h
+++ b/include/libcamera/internal/ipc_pipe_unixsocket.h
@@ -35,7 +35,7 @@ private:
 		bool done;
 	};
 
-	void readyRead(IPCUnixSocket *socket);
+	void readyRead();
 	int call(const IPCUnixSocket::Payload &message,
 		 IPCUnixSocket::Payload *response, uint32_t seq);
 
diff --git a/include/libcamera/internal/ipc_unixsocket.h b/include/libcamera/internal/ipc_unixsocket.h
index 9f5b06773..2b87196c4 100644
--- a/include/libcamera/internal/ipc_unixsocket.h
+++ b/include/libcamera/internal/ipc_unixsocket.h
@@ -37,7 +37,7 @@ public:
 	int send(const Payload &payload);
 	int receive(Payload *payload);
 
-	Signal<IPCUnixSocket *> readyRead;
+	Signal<> readyRead;
 
 private:
 	struct Header {
@@ -48,7 +48,7 @@ private:
 	int sendData(const void *buffer, size_t length, const int32_t *fds, unsigned int num);
 	int recvData(void *buffer, size_t length, int32_t *fds, unsigned int num);
 
-	void dataNotifier(EventNotifier *notifier);
+	void dataNotifier();
 
 	int fd_;
 	bool headerReceived_;
diff --git a/include/libcamera/internal/media_device.h b/include/libcamera/internal/media_device.h
index 3a7722c2a..1f2304c19 100644
--- a/include/libcamera/internal/media_device.h
+++ b/include/libcamera/internal/media_device.h
@@ -53,7 +53,7 @@ public:
 	MediaLink *link(const MediaPad *source, const MediaPad *sink);
 	int disableLinks();
 
-	Signal<MediaDevice *> disconnected;
+	Signal<> disconnected;
 
 protected:
 	std::string logPrefix() const override;
diff --git a/include/libcamera/internal/process.h b/include/libcamera/internal/process.h
index c4d5d9c1c..300e0521e 100644
--- a/include/libcamera/internal/process.h
+++ b/include/libcamera/internal/process.h
@@ -38,7 +38,7 @@ public:
 
 	void kill();
 
-	Signal<Process *, enum ExitStatus, int> finished;
+	Signal<enum ExitStatus, int> finished;
 
 private:
 	void closeAllFdsExcept(const std::vector<int> &fds);
@@ -70,7 +70,7 @@ public:
 private:
 	static ProcessManager *self_;
 
-	void sighandler(EventNotifier *notifier);
+	void sighandler();
 
 	std::list<Process *> processes_;
 
diff --git a/include/libcamera/internal/v4l2_device.h b/include/libcamera/internal/v4l2_device.h
index 423c8fb11..f21bc3701 100644
--- a/include/libcamera/internal/v4l2_device.h
+++ b/include/libcamera/internal/v4l2_device.h
@@ -65,7 +65,7 @@ private:
 	void updateControls(ControlList *ctrls,
 			    Span<const v4l2_ext_control> v4l2Ctrls);
 
-	void eventAvailable(EventNotifier *notifier);
+	void eventAvailable();
 
 	std::map<unsigned int, struct v4l2_query_ext_ctrl> controlInfo_;
 	std::vector<std::unique_ptr<ControlId>> controlIds_;
diff --git a/include/libcamera/internal/v4l2_videodevice.h b/include/libcamera/internal/v4l2_videodevice.h
index 4a5d2cadc..7a145f608 100644
--- a/include/libcamera/internal/v4l2_videodevice.h
+++ b/include/libcamera/internal/v4l2_videodevice.h
@@ -238,7 +238,7 @@ private:
 	std::unique_ptr<FrameBuffer> createBuffer(unsigned int index);
 	FileDescriptor exportDmabufFd(unsigned int index, unsigned int plane);
 
-	void bufferAvailable(EventNotifier *notifier);
+	void bufferAvailable();
 	FrameBuffer *dequeueBuffer();
 
 	V4L2Capability caps_;
diff --git a/src/libcamera/base/event_dispatcher_poll.cpp b/src/libcamera/base/event_dispatcher_poll.cpp
index 4f22f5793..3c9a126c0 100644
--- a/src/libcamera/base/event_dispatcher_poll.cpp
+++ b/src/libcamera/base/event_dispatcher_poll.cpp
@@ -278,7 +278,7 @@ void EventDispatcherPoll::processNotifiers(const std::vector<struct pollfd> &pol
 			}
 
 			if (pfd.revents & event.events)
-				notifier->activated.emit(notifier);
+				notifier->activated.emit();
 		}
 
 		/* Erase the notifiers_ entry if it is now empty. */
@@ -300,7 +300,7 @@ void EventDispatcherPoll::processTimers()
 
 		timers_.pop_front();
 		timer->stop();
-		timer->timeout.emit(timer);
+		timer->timeout.emit();
 	}
 }
 
diff --git a/src/libcamera/base/thread.cpp b/src/libcamera/base/thread.cpp
index bd7b73911..d0ca30e3d 100644
--- a/src/libcamera/base/thread.cpp
+++ b/src/libcamera/base/thread.cpp
@@ -384,7 +384,7 @@ void Thread::finishThread()
 	data_->running_ = false;
 	data_->mutex_.unlock();
 
-	finished.emit(this);
+	finished.emit();
 	data_->cv_.notify_all();
 }
 
diff --git a/src/libcamera/camera.cpp b/src/libcamera/camera.cpp
index 984383122..71809bcd3 100644
--- a/src/libcamera/camera.cpp
+++ b/src/libcamera/camera.cpp
@@ -688,7 +688,7 @@ void Camera::disconnect()
 	LOG(Camera, Debug) << "Disconnecting camera " << id();
 
 	_d()->disconnect();
-	disconnected.emit(this);
+	disconnected.emit();
 }
 
 int Camera::exportFrameBuffers(Stream *stream,
diff --git a/src/libcamera/device_enumerator.cpp b/src/libcamera/device_enumerator.cpp
index ec59927ea..d12580505 100644
--- a/src/libcamera/device_enumerator.cpp
+++ b/src/libcamera/device_enumerator.cpp
@@ -288,7 +288,7 @@ void DeviceEnumerator::removeDevice(const std::string &deviceNode)
 	LOG(DeviceEnumerator, Debug)
 		<< "Media device for node " << deviceNode << " removed.";
 
-	media->disconnected.emit(media.get());
+	media->disconnected.emit();
 }
 
 /**
diff --git a/src/libcamera/device_enumerator_udev.cpp b/src/libcamera/device_enumerator_udev.cpp
index 37a2c5aa5..5317afbd7 100644
--- a/src/libcamera/device_enumerator_udev.cpp
+++ b/src/libcamera/device_enumerator_udev.cpp
@@ -327,7 +327,7 @@ int DeviceEnumeratorUdev::addV4L2Device(dev_t devnum)
 	return 0;
 }
 
-void DeviceEnumeratorUdev::udevNotify([[maybe_unused]] EventNotifier *notifier)
+void DeviceEnumeratorUdev::udevNotify()
 {
 	struct udev_device *dev = udev_monitor_receive_device(monitor_);
 	std::string action(udev_device_get_action(dev));
diff --git a/src/libcamera/ipc_pipe_unixsocket.cpp b/src/libcamera/ipc_pipe_unixsocket.cpp
index 38bcc30a2..533560cf9 100644
--- a/src/libcamera/ipc_pipe_unixsocket.cpp
+++ b/src/libcamera/ipc_pipe_unixsocket.cpp
@@ -82,7 +82,7 @@ int IPCPipeUnixSocket::sendAsync(const IPCMessage &data)
 	return 0;
 }
 
-void IPCPipeUnixSocket::readyRead([[maybe_unused]] IPCUnixSocket *socket)
+void IPCPipeUnixSocket::readyRead()
 {
 	IPCUnixSocket::Payload payload;
 	int ret = socket_->receive(&payload);
diff --git a/src/libcamera/ipc_unixsocket.cpp b/src/libcamera/ipc_unixsocket.cpp
index 7188cf29e..bd32fca3a 100644
--- a/src/libcamera/ipc_unixsocket.cpp
+++ b/src/libcamera/ipc_unixsocket.cpp
@@ -311,7 +311,7 @@ int IPCUnixSocket::recvData(void *buffer, size_t length,
 	return 0;
 }
 
-void IPCUnixSocket::dataNotifier([[maybe_unused]] EventNotifier *notifier)
+void IPCUnixSocket::dataNotifier()
 {
 	int ret;
 
@@ -342,7 +342,7 @@ void IPCUnixSocket::dataNotifier([[maybe_unused]] EventNotifier *notifier)
 		return;
 
 	notifier_->setEnabled(false);
-	readyRead.emit(this);
+	readyRead.emit();
 }
 
 } /* namespace libcamera */
diff --git a/src/libcamera/pipeline_handler.cpp b/src/libcamera/pipeline_handler.cpp
index 597d4c6a5..f69c4f03b 100644
--- a/src/libcamera/pipeline_handler.cpp
+++ b/src/libcamera/pipeline_handler.cpp
@@ -448,7 +448,7 @@ void PipelineHandler::registerCamera(std::shared_ptr<Camera> camera)
  */
 void PipelineHandler::hotplugMediaDevice(MediaDevice *media)
 {
-	media->disconnected.connect(this, &PipelineHandler::mediaDeviceDisconnected);
+	media->disconnected.connect(this, [=]() { mediaDeviceDisconnected(media); });
 }
 
 /**
diff --git a/src/libcamera/process.cpp b/src/libcamera/process.cpp
index 998d08c2d..eca1b3003 100644
--- a/src/libcamera/process.cpp
+++ b/src/libcamera/process.cpp
@@ -66,7 +66,7 @@ void sigact(int signal, siginfo_t *info, void *ucontext)
 
 } /* namespace */
 
-void ProcessManager::sighandler([[maybe_unused]] EventNotifier *notifier)
+void ProcessManager::sighandler()
 {
 	char data;
 	ssize_t ret = read(pipe_[0], &data, sizeof(data));
@@ -326,7 +326,7 @@ void Process::died(int wstatus)
 	exitStatus_ = WIFEXITED(wstatus) ? NormalExit : SignalExit;
 	exitCode_ = exitStatus_ == NormalExit ? WEXITSTATUS(wstatus) : -1;
 
-	finished.emit(this, exitStatus_, exitCode_);
+	finished.emit(exitStatus_, exitCode_);
 }
 
 /**
diff --git a/src/libcamera/v4l2_device.cpp b/src/libcamera/v4l2_device.cpp
index 951592c69..9c783c9cb 100644
--- a/src/libcamera/v4l2_device.cpp
+++ b/src/libcamera/v4l2_device.cpp
@@ -705,12 +705,11 @@ void V4L2Device::updateControls(ControlList *ctrls,
 
 /**
  * \brief Slot to handle V4L2 events from the V4L2 device
- * \param[in] notifier The event notifier
  *
  * When this slot is called, a V4L2 event is available to be dequeued from the
  * device.
  */
-void V4L2Device::eventAvailable([[maybe_unused]] EventNotifier *notifier)
+void V4L2Device::eventAvailable()
 {
 	struct v4l2_event event{};
 	int ret = ioctl(VIDIOC_DQEVENT, &event);
diff --git a/src/libcamera/v4l2_videodevice.cpp b/src/libcamera/v4l2_videodevice.cpp
index 9d35618d1..4e1c2b7ce 100644
--- a/src/libcamera/v4l2_videodevice.cpp
+++ b/src/libcamera/v4l2_videodevice.cpp
@@ -1524,7 +1524,6 @@ int V4L2VideoDevice::queueBuffer(FrameBuffer *buffer)
 
 /**
  * \brief Slot to handle completed buffer events from the V4L2 video device
- * \param[in] notifier The event notifier
  *
  * When this slot is called, a Buffer has become available from the device, and
  * will be emitted through the bufferReady Signal.
@@ -1532,7 +1531,7 @@ int V4L2VideoDevice::queueBuffer(FrameBuffer *buffer)
  * For Capture video devices the FrameBuffer will contain valid data.
  * For Output video devices the FrameBuffer can be considered empty.
  */
-void V4L2VideoDevice::bufferAvailable([[maybe_unused]] EventNotifier *notifier)
+void V4L2VideoDevice::bufferAvailable()
 {
 	FrameBuffer *buffer = dequeueBuffer();
 	if (!buffer)
diff --git a/test/event-thread.cpp b/test/event-thread.cpp
index 12021710e..ef8a52c3d 100644
--- a/test/event-thread.cpp
+++ b/test/event-thread.cpp
@@ -66,7 +66,7 @@ public:
 	}
 
 private:
-	void readReady([[maybe_unused]] EventNotifier *notifier)
+	void readReady()
 	{
 		size_ = read(notifier_->fd(), data_, sizeof(data_));
 		notified_ = true;
diff --git a/test/event.cpp b/test/event.cpp
index e338335c1..d4765eb14 100644
--- a/test/event.cpp
+++ b/test/event.cpp
@@ -22,7 +22,7 @@ using namespace libcamera;
 class EventTest : public Test
 {
 protected:
-	void readReady([[maybe_unused]] EventNotifier *notifier)
+	void readReady()
 	{
 		size_ = read(notifier_->fd(), data_, sizeof(data_));
 		notified_ = true;
diff --git a/test/ipa/ipa_interface_test.cpp b/test/ipa/ipa_interface_test.cpp
index 0ee51f71f..43562e608 100644
--- a/test/ipa/ipa_interface_test.cpp
+++ b/test/ipa/ipa_interface_test.cpp
@@ -153,7 +153,7 @@ protected:
 	}
 
 private:
-	void readTrace([[maybe_unused]] EventNotifier *notifier)
+	void readTrace()
 	{
 		ssize_t s = read(notifier_->fd(), &trace_, sizeof(trace_));
 		if (s < 0) {
diff --git a/test/ipc/unixsocket.cpp b/test/ipc/unixsocket.cpp
index 6507fb12d..7270bf4d2 100644
--- a/test/ipc/unixsocket.cpp
+++ b/test/ipc/unixsocket.cpp
@@ -68,7 +68,7 @@ public:
 	}
 
 private:
-	void readyRead([[maybe_unused]] IPCUnixSocket *ipc)
+	void readyRead()
 	{
 		IPCUnixSocket::Payload message, response;
 		int ret;
@@ -447,7 +447,7 @@ private:
 		return 0;
 	}
 
-	void readyRead([[maybe_unused]] IPCUnixSocket *ipc)
+	void readyRead()
 	{
 		if (!callResponse_) {
 			cerr << "Read ready without expecting data, fail." << endl;
diff --git a/test/ipc/unixsocket_ipc.cpp b/test/ipc/unixsocket_ipc.cpp
index 60317a495..ab5d25572 100644
--- a/test/ipc/unixsocket_ipc.cpp
+++ b/test/ipc/unixsocket_ipc.cpp
@@ -65,7 +65,7 @@ public:
 	}
 
 private:
-	void readyRead([[maybe_unused]] IPCUnixSocket *ipc)
+	void readyRead()
 	{
 		IPCUnixSocket::Payload message;
 		int ret;
diff --git a/test/log/log_process.cpp b/test/log/log_process.cpp
index d138aa7ff..a56a39984 100644
--- a/test/log/log_process.cpp
+++ b/test/log/log_process.cpp
@@ -126,8 +126,7 @@ protected:
 	}
 
 private:
-	void procFinished([[maybe_unused]] Process *proc,
-			  enum Process::ExitStatus exitStatus, int exitCode)
+	void procFinished(enum Process::ExitStatus exitStatus, int exitCode)
 	{
 		exitStatus_ = exitStatus;
 		exitCode_ = exitCode;
diff --git a/test/process/process_test.cpp b/test/process/process_test.cpp
index 8f7a1f05f..378d680bf 100644
--- a/test/process/process_test.cpp
+++ b/test/process/process_test.cpp
@@ -81,8 +81,7 @@ protected:
 	}
 
 private:
-	void procFinished([[maybe_unused]] Process *proc,
-			  enum Process::ExitStatus exitStatus, int exitCode)
+	void procFinished(enum Process::ExitStatus exitStatus, int exitCode)
 	{
 		exitStatus_ = exitStatus;
 		exitCode_ = exitCode;
diff --git a/test/timer-thread.cpp b/test/timer-thread.cpp
index 2c14865b7..f7e8743da 100644
--- a/test/timer-thread.cpp
+++ b/test/timer-thread.cpp
@@ -39,7 +39,7 @@ public:
 	}
 
 private:
-	void timeoutHandler([[maybe_unused]] Timer *timer)
+	void timeoutHandler()
 	{
 		timeout_ = true;
 	}
diff --git a/test/timer.cpp b/test/timer.cpp
index 88f226e79..be79d0100 100644
--- a/test/timer.cpp
+++ b/test/timer.cpp
@@ -56,7 +56,7 @@ public:
 	}
 
 private:
-	void timeoutHandler([[maybe_unused]] Timer *timer)
+	void timeoutHandler()
 	{
 		expiration_ = std::chrono::steady_clock::now();
 		count_++;
diff --git a/utils/ipc/generators/libcamera_templates/module_ipa_proxy_worker.cpp.tmpl b/utils/ipc/generators/libcamera_templates/module_ipa_proxy_worker.cpp.tmpl
index b4cd1aa9e..c54ecdb90 100644
--- a/utils/ipc/generators/libcamera_templates/module_ipa_proxy_worker.cpp.tmpl
+++ b/utils/ipc/generators/libcamera_templates/module_ipa_proxy_worker.cpp.tmpl
@@ -57,7 +57,7 @@ public:
 
 	~{{proxy_worker_name}}() {}
 
-	void readyRead([[maybe_unused]] IPCUnixSocket *socket)
+	void readyRead()
 	{
 		IPCUnixSocket::Payload _message;
 		int _retRecv = socket_.receive(&_message);