diff --git a/meshroom/core/__init__.py b/meshroom/core/__init__.py
index fe9ec170..82635202 100644
--- a/meshroom/core/__init__.py
+++ b/meshroom/core/__init__.py
@@ -31,7 +31,6 @@ logging.basicConfig(format='[%(asctime)s][%(levelname)s] %(message)s', level=log
 sessionUid = str(uuid.uuid1())
 
 cacheFolderName = 'MeshroomCache'
-defaultCacheFolder = os.environ.get('MESHROOM_CACHE', os.path.join(tempfile.gettempdir(), cacheFolderName))
 nodesDesc = {}
 submitters = {}
 pipelineTemplates = {}
diff --git a/meshroom/core/desc/node.py b/meshroom/core/desc/node.py
index 2cbec111..e524037e 100644
--- a/meshroom/core/desc/node.py
+++ b/meshroom/core/desc/node.py
@@ -25,18 +25,6 @@ class MrNodeType(enum.Enum):
     COMMANDLINE = enum.auto()
     INPUT = enum.auto()
 
-def isNodeSaved(node):
-    """Returns whether a node is identical to its serialized counterpart in the current graph file."""
-    filepath = node.graph.filepath
-    if not filepath:
-        return False
-
-    from meshroom.core.graph import loadGraph
-    graphSaved = loadGraph(filepath)
-    nodeSaved = graphSaved.node(node.name)
-    if nodeSaved is None:
-        return False
-    return nodeSaved._uid == node._uid
 
 class BaseNode(object):
     """
@@ -259,9 +247,6 @@ class Node(BaseNode):
         return MrNodeType.NODE
 
     def processChunkInEnvironment(self, chunk):
-        if not isNodeSaved(chunk.node):
-            raise RuntimeError("File must be saved before computing in isolated environment.")
-
         meshroomComputeCmd = f"python {_MESHROOM_COMPUTE} {chunk.node.graph.filepath} --node {chunk.node.name} --extern --inCurrentEnv"
         if len(chunk.node.getChunks()) > 1:
             meshroomComputeCmd += f" --iteration {chunk.range.iteration}"
diff --git a/meshroom/core/graph.py b/meshroom/core/graph.py
index 11cb1965..ab28bcc3 100644
--- a/meshroom/core/graph.py
+++ b/meshroom/core/graph.py
@@ -182,7 +182,6 @@ class Graph(BaseObject):
         edges = {B.input: A.output, C.input: B.output,}
 
     """
-    _cacheDir = ""
 
     def __init__(self, name, parent=None):
         super(Graph, self).__init__(parent)
@@ -199,7 +198,7 @@ class Graph(BaseObject):
         # Edges: use dst attribute as unique key since it can only have one input connection
         self._edges = DictModel(keyAttrName='dst', parent=self)
         self._compatibilityNodes = DictModel(keyAttrName='name', parent=self)
-        self.cacheDir = meshroom.core.defaultCacheFolder
+        self._cacheDir = ''
         self._filepath = ''
         self._fileDateVersion = 0
         self.header = {}
@@ -1354,7 +1353,7 @@ class Graph(BaseObject):
     def _unsetFilepath(self):
         self._filepath = ""
         self.name = ""
-        self.cacheDir = meshroom.core.defaultCacheFolder
+        self.cacheDir = ""
         self.filepathChanged.emit()
 
     def updateInternals(self, startNodes=None, force=False):
diff --git a/meshroom/env.py b/meshroom/env.py
index 46ce30e9..ddd48577 100644
--- a/meshroom/env.py
+++ b/meshroom/env.py
@@ -12,9 +12,9 @@ import os
 from dataclasses import dataclass
 from enum import Enum
 import sys
+import tempfile
 from typing import Any, Type
 
-
 meshroomFolder = os.path.dirname(__file__)
 
 @dataclass
@@ -46,6 +46,8 @@ class EnvVar(Enum):
     MESHROOM_NODES_PATH = VarDefinition(str, "", "Paths to set of nodes folders")
     MESHROOM_SUBMITTERS_PATH = VarDefinition(str, "", "Paths to set of submitters folders")
     MESHROOM_PIPELINE_TEMPLATES_PATH = VarDefinition(str, "", "Paths to et of pipeline templates folders")
+    MESHROOM_TEMP_PATH = VarDefinition(str, tempfile.gettempdir(), "Path to the temporary folder")
+
 
     @staticmethod
     def get(envVar: "EnvVar") -> Any:
diff --git a/meshroom/ui/graph.py b/meshroom/ui/graph.py
index a41430b2..d5062bf8 100644
--- a/meshroom/ui/graph.py
+++ b/meshroom/ui/graph.py
@@ -514,6 +514,14 @@ class UIGraph(QObject):
         # => force re-evaluation of monitored status files paths
         self.updateChunkMonitor(self._sortedDFSChunks)
 
+    @Slot()
+    def saveAsTemp(self):
+        from meshroom.env import EnvVar
+        from datetime import datetime
+        tempFolder = EnvVar.get(EnvVar.MESHROOM_TEMP_PATH)
+        timestamp = datetime.now().strftime("%Y-%m-%d_%H:%M")
+        self._saveAs(os.path.join(tempFolder, f"meshroom_{timestamp}.mg"))
+
     @Slot()
     def save(self):
         self._graph.save()
@@ -531,6 +539,7 @@ class UIGraph(QObject):
     @Slot(list)
     def execute(self, nodes: Optional[Union[list[Node], Node]] = None):
         nodes = [nodes] if not isinstance(nodes, Iterable) and nodes else nodes
+        self.save()  # always save the graph before computing
         self._taskManager.compute(self._graph, nodes)
         self.updateLockedUndoStack()  # explicitly call the update while it is already computing
 
diff --git a/meshroom/ui/qml/Application.qml b/meshroom/ui/qml/Application.qml
index ef91bcca..59e04d12 100644
--- a/meshroom/ui/qml/Application.qml
+++ b/meshroom/ui/qml/Application.qml
@@ -134,6 +134,8 @@ Page {
         id: saveFileDialog
         options: Platform.FileDialog.DontUseNativeDialog
 
+        property var _callback: undefined
+
         signal closed(var result)
 
         title: "Save File"
@@ -150,8 +152,28 @@ Page {
             _reconstruction.saveAs(currentFile)
             MeshroomApp.addRecentProjectFile(currentFile.toString())
             closed(Platform.Dialog.Accepted)
+            fireCallback(Platform.Dialog.Accepted)
+        }
+        onRejected: {
+            closed(Platform.Dialog.Rejected)
+            fireCallback(Platform.Dialog.Rejected)
+        }
+
+        function fireCallback(rc)
+        {
+            // Call the callback and reset it
+            if (_callback)
+                _callback(rc)
+            _callback = undefined
+        }
+
+        // Open the unsaved dialog warning with an optional
+        // callback to fire when the dialog is accepted/discarded
+        function prompt(callback)
+        {
+            _callback = callback
+            open()
         }
-        onRejected: closed(Platform.Dialog.Rejected)
     }
 
     Platform.FileDialog {
@@ -218,8 +240,6 @@ Page {
     Item {
         id: computeManager
 
-        property bool warnIfUnsaved: true
-
         // Evaluate if graph computation can be submitted externally
         property bool canSubmit: _reconstruction ?
                                  _reconstruction.canSubmit                 // current setup allows to compute externally
@@ -227,7 +247,7 @@ Page {
                                  false
 
         function compute(nodes, force) {
-            if (!force && warnIfUnsaved && !_reconstruction.graph.filepath) {
+            if (!force && !_reconstruction.graph.filepath) {
                 unsavedComputeDialog.selectedNodes = nodes;
                 unsavedComputeDialog.open();
             }
@@ -339,29 +359,28 @@ Page {
             parent: Overlay.overlay
             preset: "Warning"
             title: "Unsaved Project"
-            text: "Data will be computed in the default cache folder if project remains unsaved."
-            detailedText: "Default cache folder: " + (_reconstruction ? _reconstruction.graph.cacheDir : "unknown")
-            helperText: "Save project first?"
+            text: "Saving the project is required."
+            helperText: "Choose a location to save the project, or use the default temporary path."
             standardButtons: Dialog.Discard | Dialog.Cancel | Dialog.Save
 
-            CheckBox {
-                Layout.alignment: Qt.AlignRight
-                text: "Don't ask again for this session"
-                padding: 0
-                onToggled: computeManager.warnIfUnsaved = !checked
-            }
-
             Component.onCompleted: {
                 // Set up discard button text
-                standardButton(Dialog.Discard).text = "Continue without Saving"
+                standardButton(Dialog.Discard).text = "Continue in Temp Folder"
+                standardButton(Dialog.Save).text = "Save As"
             }
 
             onDiscarded: {
+                _reconstruction.saveAsTemp()
                 close()
                 computeManager.compute(selectedNodes, true)
             }
 
-            onAccepted: saveAsAction.trigger()
+            onAccepted: {
+                initFileDialogFolder(saveFileDialog)
+                saveFileDialog.prompt(function(rc) {
+                    computeManager.compute(selectedNodes, true)
+                })
+            }
         }
 
         MessageDialog {
@@ -444,14 +463,10 @@ Page {
             }
             // Open "Save As" dialog
             else {
-                saveFileDialog.open()
-                function _callbackWrapper(rc) {
+                saveFileDialog.prompt(function(rc) {
                     if (rc === Platform.Dialog.Accepted)
                         fireCallback()
-
-                    saveFileDialog.closed.disconnect(_callbackWrapper)
-                }
-                saveFileDialog.closed.connect(_callbackWrapper)
+                })
             }
         }
 
@@ -463,8 +478,8 @@ Page {
             _callback = undefined
         }
 
-        /// Open the unsaved dialog warning with an optional
-        /// callback to fire when the dialog is accepted/discarded
+        // Open the unsaved dialog warning with an optional
+        // callback to fire when the dialog is accepted/discarded
         function prompt(callback)
         {
             _callback = callback