diff --git a/README b/README
index 6545880..b802851 100644
--- a/README
+++ b/README
@@ -1,39 +1,17 @@
 Installing into private directory
 =================================
 
-For whatever reason, it might be useful to install the
-python frontend into a private directory.
-Here are some examples on how to do it:
+1. Create a venv and include the system-site packages:
+   `python3 -m venv venv --system-site-packages`
+2. Active that venv: `. venv/bin/activate`
+3. Install an editable package: `pip install --no-deps -e .`
 
-	python setup.py install --home=/opt/damaris-private
-or
-	python setup.py install --home=$HOME/devel/damaris-installed
+This will use the system packages already installed.
 
-To start Damaris use for example:
+Alternatively you can install withoout the system-site-packages:
 
-	/opt/damaris-private/bin/DAMARIS
+    python3 -m venv venv
+    . venv/bin/activate
+    pip install -e .
 
-
-Updating debian/changelog
-=========================
-
-Subversion
-==========
-
-Use the following command to get all the commit messages:
-
-Mac OS X:
-
-svn2cl -i -a --stdout |gsed 's/^\t/  /'|gsed -e '/^[0-9]/d'
-
-Linux:
-
-svn2cl -i -a --stdout |sed 's/^\t/  /'|sed -e '/^[0-9]/d'
-
-Git
-===
-git log --oneline  .
-
-
-Then pick the stuff the users need to know.
-dch -M -v x.xx
+This will download newer packages and install them in the venv.
diff --git a/requirements.debian b/requirements.debian
index 3d1e50f..e8ba18b 100644
--- a/requirements.debian
+++ b/requirements.debian
@@ -1,3 +1,18 @@
+#!/bin/bash
 sudo apt install libcairo2-dev 
-sudo apt install libgirepository-2.0-dev gir1.2-gtksource-3.0
-
+sudo apt install python3-scipy python3-lmfit python3-matplotlib
+sudo apt install gir1.2-gtksource-3.0
+DEBRELEASE=$(lsb_release -cs)
+case $DEBRELEASE in
+  "trixie")
+	echo "Trixie detected"
+	sudo apt install libgirepository-2.0-dev 
+	;;
+  "bookworm")
+	echo "Bookworm detected"
+	sudo apt install libgirepository1.0-dev
+	;;
+  *)
+  echo "not implemented" ; exit 1
+  ;;
+esac
diff --git a/src/tests/debugging-gtk.sh b/src/tests/debugging-gtk.sh
new file mode 100644
index 0000000..2c069a5
--- /dev/null
+++ b/src/tests/debugging-gtk.sh
@@ -0,0 +1,12 @@
+# 1. disable any possible re-launch
+GIO_USE_VFS=local             # stop gvfs daemonising
+GSETTINGS_BACKEND=memory        # don’t spawn dconf-service
+
+# 2. ask glib to abort on the first warning so nothing can “eat” it
+G_DEBUG=fatal-warnings        # or =fatal-criticals
+
+# 3. turn on *all* debug domains
+G_MESSAGES_DEBUG=all
+
+# 4. run inside gdb so we can see the exact line that fails
+gdb -ex run --args python3 src/gui/DamarisGUI.py
diff --git a/src/tests/gtk3test.py b/src/tests/gtk3test.py
new file mode 100644
index 0000000..7f2ebd5
--- /dev/null
+++ b/src/tests/gtk3test.py
@@ -0,0 +1,8 @@
+import gi
+gi.require_version('Gtk', '3.0')
+from gi.repository import Gtk
+print("GTK imported successfully")
+win = Gtk.Window()
+win.connect("destroy", Gtk.main_quit)
+win.show_all()
+Gtk.main()
diff --git a/src/tests/mpltest.py b/src/tests/mpltest.py
new file mode 100644
index 0000000..098c8c8
--- /dev/null
+++ b/src/tests/mpltest.py
@@ -0,0 +1,23 @@
+#!/usr/bin/env python3
+import os
+import sys
+
+# 1) force GTK3 backend *before* pyplot is imported
+os.environ['MPLBACKEND'] = 'GTK3Agg'   # or GTK3Cairo
+
+# 2) turn on every debug message GLib/GTK will give us
+os.environ['G_MESSAGES_DEBUG'] = 'all'
+os.environ['GTK_DEBUG'] = 'interactive'   # also enables Ctrl-Shift-I inspector
+
+import matplotlib
+matplotlib.use('GTK3Agg')          # belt-and-braces: make sure
+import matplotlib.pyplot as plt
+
+print('GTK3Agg backend loaded, creating figure…')
+fig, ax = plt.subplots()
+ax.plot([0, 1], [0, 1])
+ax.set_title('GTK3-Matplotlib window – close it to finish')
+print('Showing figure…')
+plt.show()
+print('plt.show() returned – script ends')
+
diff --git a/src/tests/scripts/exp.py b/src/tests/scripts/exp.py
new file mode 100644
index 0000000..e69de29
diff --git a/src/tests/scripts/res.py b/src/tests/scripts/res.py
new file mode 100644
index 0000000..e69de29