diff --git a/zxlive/commands.py b/zxlive/commands.py
index a898a73d..e8553ef8 100644
--- a/zxlive/commands.py
+++ b/zxlive/commands.py
@@ -423,6 +423,10 @@ class GoToRewriteStep(SetGraph):
     def __init__(self, graph_view: GraphView, step_view: QListView, old_step: int, step: int) -> None:
         proof_model = step_view.model()
         assert isinstance(proof_model, ProofModel)
+
+        # Save any vertex rearrangements to the proof step
+        proof_model.set_graph(old_step, graph_view.graph_scene.g)
+
         SetGraph.__init__(self, graph_view, proof_model.get_graph(step))
         self.step_view = step_view
         self.step = step
@@ -445,20 +449,3 @@ def undo(self) -> None:
         self.step_view.selectionModel().blockSignals(False)
         self.step_view.update(idx)
         super().undo()
-
-
-@dataclass
-class MoveNodeInStep(MoveNode):
-    step_view: QListView
-
-    def redo(self) -> None:
-        super().redo()
-        model = self.step_view.model()
-        assert isinstance(model, ProofModel)
-        model.set_graph(self.step_view.currentIndex().row(), self.g)
-
-    def undo(self) -> None:
-        super().undo()
-        model = self.step_view.model()
-        assert isinstance(model, ProofModel)
-        model.set_graph(self.step_view.currentIndex().row(), self.g)
diff --git a/zxlive/proof_panel.py b/zxlive/proof_panel.py
index f0ec1b6a..e962670b 100644
--- a/zxlive/proof_panel.py
+++ b/zxlive/proof_panel.py
@@ -18,7 +18,7 @@
 
 from . import animations as anims
 from .base_panel import BasePanel, ToolbarSection
-from .commands import AddRewriteStep, GoToRewriteStep, MoveNodeInStep, UndoableChange
+from .commands import AddRewriteStep, GoToRewriteStep, MoveNode, UndoableChange
 from .common import (ET, VT, GraphT, get_data,
                      pos_from_view, pos_to_view, colors)
 from .dialogs import show_error_msg
@@ -156,7 +156,7 @@ def parse_selection(self) -> tuple[list[VT], list[ET]]:
         return selection, list(edges)
 
     def _vert_moved(self, vs: list[tuple[VT, float, float]]) -> None:
-        cmd = MoveNodeInStep(self.graph_view, vs, self.step_view)
+        cmd = MoveNode(self.graph_view, vs)
         self.undo_stack.push(cmd)
 
     def _selection_clicked(self) -> None:
diff --git a/zxlive/rewrite_data.py b/zxlive/rewrite_data.py
index 76de351e..01cf7b48 100644
--- a/zxlive/rewrite_data.py
+++ b/zxlive/rewrite_data.py
@@ -94,6 +94,19 @@ def _extract_circuit(graph: GraphT, matches: list) -> GraphT:
     return extract_circuit(graph).to_graph()
 
 
+# The OCM action simply saves the current graph without modifying anything.
+# This can be used to make repositioning the vertices an explicit proof step.
+def ocm_rule(_graph: GraphT, _matches: list) -> pyzx.rules.RewriteOutputType[ET, VT]:
+    return ({}, [], [], True)
+
+ocm_action: RewriteData = {
+        "text": "OCM",
+        "tooltip": "Saves the graph with the current vertex positions",
+        "matcher": const_true,
+        "rule": ocm_rule,
+        "type": MATCHES_VERTICES,
+}
+
 simplifications: dict[str, RewriteData] = {
     'bialg_simp': {
         "text": "bialgebra",
@@ -239,6 +252,7 @@ def _extract_circuit(graph: GraphT, matches: list) -> GraphT:
 
 action_groups = {
     "Basic rules": {key: operations[key] for key in rules_basic},
+    "OCM": ocm_action,
     "Custom rules": {},
     "Graph-like rules": rewrites_graph_theoretic,
     "ZXW rules": {key: operations[key] for key in rules_zxw},