diff --git a/artiq/applets/big_number.py b/artiq/applets/big_number.py
index a085ce8e4..56458f507 100755
--- a/artiq/applets/big_number.py
+++ b/artiq/applets/big_number.py
@@ -22,10 +22,10 @@ class QCancellableLineEdit(QtWidgets.QLineEdit):
 
 
 class NumberWidget(QtWidgets.QStackedWidget):
-    def __init__(self, args, ctl):
+    def __init__(self, args, req):
         QtWidgets.QStackedWidget.__init__(self)
         self.dataset_name = args.dataset
-        self.ctl = ctl
+        self.req = req
 
         self.lcd_widget = QResponsiveLCDNumber()
         self.lcd_widget.setDigitCount(args.digit_count)
@@ -55,7 +55,7 @@ class NumberWidget(QtWidgets.QStackedWidget):
 
     def confirm_edit(self):
         value = float(self.edit_widget.text())
-        self.ctl.set_dataset(self.dataset_name, value)
+        self.req.set_dataset(self.dataset_name, value)
         self.setCurrentWidget(self.lcd_widget)
 
     def cancel_edit(self):
diff --git a/artiq/applets/image.py b/artiq/applets/image.py
index 36af01cab..75cecd05a 100755
--- a/artiq/applets/image.py
+++ b/artiq/applets/image.py
@@ -7,7 +7,7 @@ from artiq.applets.simple import SimpleApplet
 
 
 class Image(pyqtgraph.ImageView):
-    def __init__(self, args, ctl):
+    def __init__(self, args, req):
         pyqtgraph.ImageView.__init__(self)
         self.args = args
 
diff --git a/artiq/applets/plot_hist.py b/artiq/applets/plot_hist.py
index 3be604930..5d386cc6c 100755
--- a/artiq/applets/plot_hist.py
+++ b/artiq/applets/plot_hist.py
@@ -8,7 +8,7 @@ from artiq.applets.simple import TitleApplet
 
 
 class HistogramPlot(pyqtgraph.PlotWidget):
-    def __init__(self, args, ctl):
+    def __init__(self, args, req):
         pyqtgraph.PlotWidget.__init__(self)
         self.args = args
         self.timer = QTimer()
diff --git a/artiq/applets/plot_xy.py b/artiq/applets/plot_xy.py
index 3838ce345..d7d67803b 100755
--- a/artiq/applets/plot_xy.py
+++ b/artiq/applets/plot_xy.py
@@ -9,7 +9,7 @@ from artiq.applets.simple import TitleApplet
 
 
 class XYPlot(pyqtgraph.PlotWidget):
-    def __init__(self, args, ctl):
+    def __init__(self, args, req):
         pyqtgraph.PlotWidget.__init__(self)
         self.args = args
         self.timer = QTimer()
diff --git a/artiq/applets/plot_xy_hist.py b/artiq/applets/plot_xy_hist.py
index 7d42aeacc..f757b520d 100755
--- a/artiq/applets/plot_xy_hist.py
+++ b/artiq/applets/plot_xy_hist.py
@@ -22,7 +22,7 @@ def _compute_ys(histogram_bins, histograms_counts):
 # pyqtgraph.GraphicsWindow fails to behave like a regular Qt widget
 # and breaks embedding. Do not use as top widget.
 class XYHistPlot(QtWidgets.QSplitter):
-    def __init__(self, args, ctl):
+    def __init__(self, args, req):
         QtWidgets.QSplitter.__init__(self)
         self.resize(1000, 600)
         self.setWindowTitle("XY/Histogram")
diff --git a/artiq/applets/progress_bar.py b/artiq/applets/progress_bar.py
index b25d380d8..9ea7db836 100644
--- a/artiq/applets/progress_bar.py
+++ b/artiq/applets/progress_bar.py
@@ -6,7 +6,7 @@ from artiq.applets.simple import SimpleApplet
 
 
 class ProgressWidget(QtWidgets.QProgressBar):
-    def __init__(self, args, ctl):
+    def __init__(self, args, req):
         QtWidgets.QProgressBar.__init__(self)
         self.setMinimum(args.min)
         self.setMaximum(args.max)
diff --git a/artiq/applets/simple.py b/artiq/applets/simple.py
index 580991982..cd980bb34 100644
--- a/artiq/applets/simple.py
+++ b/artiq/applets/simple.py
@@ -251,21 +251,21 @@ class SimpleApplet:
         if self.embed is not None:
             self.ipc.close()
 
-    def ctl_init(self):
+    def req_init(self):
         if self.embed is None:
             dataset_ctl = RPCClient()
             self.loop.run_until_complete(dataset_ctl.connect_rpc(
                 self.args.server, self.args.port_control, "master_dataset_db"))
-            self.ctl = AppletRequestRPC(self.loop, dataset_ctl)
+            self.req = AppletRequestRPC(self.loop, dataset_ctl)
         else:
-            self.ctl = AppletRequestIPC(self.ipc)
+            self.req = AppletRequestIPC(self.ipc)
 
-    def ctl_close(self):
+    def req_close(self):
         if self.embed is None:
-            self.ctl.dataset_ctl.close_rpc()
+            self.req.dataset_ctl.close_rpc()
 
     def create_main_widget(self):
-        self.main_widget = self.main_widget_class(self.args, self.ctl)
+        self.main_widget = self.main_widget_class(self.args, self.req)
         if self.embed is not None:
             self.ipc.set_close_cb(self.main_widget.close)
             if os.name == "nt":
@@ -367,7 +367,7 @@ class SimpleApplet:
         try:
             self.ipc_init()
             try:
-                self.ctl_init()
+                self.req_init()
                 try:
                     self.create_main_widget()
                     self.subscribe()
@@ -376,7 +376,7 @@ class SimpleApplet:
                     finally:
                         self.unsubscribe()
                 finally:
-                    self.ctl_close()
+                    self.req_close()
             finally:
                 self.ipc_close()
         finally: