diff --git a/crates/doc/src/variables.rs b/crates/doc/src/variables.rs
index 360de81c9..96bccbd0a 100644
--- a/crates/doc/src/variables.rs
+++ b/crates/doc/src/variables.rs
@@ -116,6 +116,10 @@ pub struct Variables {
     pub bindings: BTreeMap<NodeId, BTreeSet<String>>,
     #[serde(default, skip_serializing_if = "Option::is_none")]
     pub active_dataset: Option<String>,
+    /// Lock Variables: while set, variables can't be defined, deleted or renamed. Objects can
+    /// still be bound to them and unbound, and datasets still change and apply.
+    #[serde(default, skip_serializing_if = "std::ops::Not::not")]
+    pub locked: bool,
 }
 
 impl Variables {
diff --git a/crates/engine/src/cmd/variablecmds.rs b/crates/engine/src/cmd/variablecmds.rs
index 3694f8e54..fb82f1f4b 100644
--- a/crates/engine/src/cmd/variablecmds.rs
+++ b/crates/engine/src/cmd/variablecmds.rs
@@ -29,6 +29,19 @@ const MAX_CSV_BYTES: usize = 1_048_576;
 const MAX_CSV_ROWS: usize = 1_000;
 const MAX_CSV_COLS: usize = 256;
 
+/// Lock Variables refuses New Variable, Delete Variable, Rename Variable (Variable Options) and
+/// Make … Dynamic; binding, unbinding and the dataset commands still run.
+fn variables_unlocked(s: &Session) -> std::result::Result<(), String> {
+    has_doc(s)?;
+    if s.active().is_some_and(|st| st.doc.variables.locked) { Err("variables are locked".into()) } else { Ok(()) }
+}
+
+/// Make … Dynamic needs a selection, and defines a variable, which Lock Variables refuses.
+fn selection_and_unlocked(s: &Session) -> std::result::Result<(), String> {
+    has_selection(s)?;
+    variables_unlocked(s)
+}
+
 fn var_name(p: &Value, cmd: &str) -> Result<String> {
     named(str_param(p, "name"), "name", cmd)
 }
@@ -232,7 +245,21 @@ fn list(s: &mut Session, _p: &Value) -> Result<Value> {
             json!({"name": v.name, "kind": v.kind.label(), "bindings": bindings})
         })
         .collect();
-    Ok(json!({"variables": variables}))
+    Ok(json!({"variables": variables, "locked": st.doc.variables.locked}))
+}
+
+/// Lock Variables: without `locked` it toggles. Setting the state the document already has
+/// does not edit the document or add an undo step.
+fn lock(s: &mut Session, p: &Value) -> Result<Value> {
+    let was = s.doc()?.doc.variables.locked;
+    let locked = bool_or(p, "locked", !was);
+    if locked != was {
+        s.edit(if locked { "Lock Variables" } else { "Unlock Variables" }, |d, _| {
+            d.variables.locked = locked;
+            Ok(())
+        })?;
+    }
+    Ok(json!({"locked": locked}))
 }
 
 fn bind(s: &mut Session, p: &Value) -> Result<Value> {
@@ -812,8 +839,8 @@ pub fn specs() -> Vec<CommandSpec> {
             "New Variable…",
             ["Window", "Variables"],
             None,
-            "{name, kind: text|visibility|image|graph} define a variable (graph: CSV data on a graph root)",
-            has_doc,
+            "{name, kind: text|visibility|image|graph} define a variable (graph: CSV data on a graph root); refused while the variables are locked",
+            variables_unlocked,
             define
         ),
         cmd!(
@@ -821,8 +848,8 @@ pub fn specs() -> Vec<CommandSpec> {
             "Delete Variable",
             ["Window", "Variables"],
             None,
-            "{names?} delete variables with their bindings and values (default: the highlighted one)",
-            has_doc,
+            "{names?} delete variables with their bindings and values (default: the highlighted one); refused while the variables are locked",
+            variables_unlocked,
             delete
         ),
         cmd!(
@@ -830,18 +857,18 @@ pub fn specs() -> Vec<CommandSpec> {
             "Rename Variable",
             ["Window", "Variables"],
             None,
-            "{name, newName} rename a variable, with its bindings and its values in every dataset",
-            has_doc,
+            "{name, newName} rename a variable, with its bindings and its values in every dataset; refused while the variables are locked",
+            variables_unlocked,
             rename
         ),
-        cmd!(query "variable.list", "List Variables", [], None, "{} → variables with kinds and binding counts", has_doc, list),
+        cmd!(query "variable.list", "List Variables", [], None, "{} → variables with kinds and binding counts, and whether they are locked → {variables, locked}", has_doc, list),
         cmd!(
             "variable.makeTextDynamic",
             "Make Text Dynamic",
             ["Window", "Variables"],
             None,
-            "{} define a text variable over the selection, named after it and bound to it",
-            has_selection,
+            "{} define a text variable over the selection, named after it and bound to it; refused while the variables are locked",
+            selection_and_unlocked,
             |s, _| make_dynamic(s, VariableKind::Text, "Text")
         ),
         cmd!(
@@ -849,8 +876,8 @@ pub fn specs() -> Vec<CommandSpec> {
             "Make Visibility Dynamic",
             ["Window", "Variables"],
             None,
-            "{} define a visibility variable over the selection, named after it and bound to it",
-            has_selection,
+            "{} define a visibility variable over the selection, named after it and bound to it; refused while the variables are locked",
+            selection_and_unlocked,
             |s, _| make_dynamic(s, VariableKind::Visibility, "Visibility")
         ),
         cmd!(
@@ -858,8 +885,8 @@ pub fn specs() -> Vec<CommandSpec> {
             "Make Image Dynamic",
             ["Window", "Variables"],
             None,
-            "{} define an image variable over the selection, named after it and bound to it",
-            has_selection,
+            "{} define an image variable over the selection, named after it and bound to it; refused while the variables are locked",
+            selection_and_unlocked,
             |s, _| make_dynamic(s, VariableKind::Image, "Image")
         ),
         cmd!(
@@ -867,8 +894,8 @@ pub fn specs() -> Vec<CommandSpec> {
             "Make Graph Dynamic",
             ["Window", "Variables"],
             None,
-            "{} define a graph variable over the selected graph root(s), named after it and bound to it; each dataset row supplies CSV as graph.setData",
-            has_selection,
+            "{} define a graph variable over the selected graph root(s), named after it and bound to it; each dataset row supplies CSV as graph.setData; refused while the variables are locked",
+            selection_and_unlocked,
             |s, _| make_dynamic(s, VariableKind::Graph, "Graph")
         ),
         cmd!(
@@ -889,6 +916,15 @@ pub fn specs() -> Vec<CommandSpec> {
             has_doc,
             unbind
         ),
+        cmd!(
+            "variable.lock",
+            "Lock Variables",
+            ["Window", "Variables"],
+            None,
+            "{locked?: bool} lock or unlock the variables (default: toggle); saved with the document; a change is one undo step. While locked, variable.define, variable.delete, variable.rename and variable.make…Dynamic are refused; binding, unbinding and the dataset commands still run → {locked}",
+            has_doc,
+            lock
+        ),
         cmd!(
             "variable.highlight",
             "Highlight Variable",
diff --git a/crates/engine/src/tests_variables.rs b/crates/engine/src/tests_variables.rs
index 62bfa9e40..b1d8d28d2 100644
--- a/crates/engine/src/tests_variables.rs
+++ b/crates/engine/src/tests_variables.rs
@@ -370,6 +370,79 @@ fn make_dynamic_errors_name_the_command() {
     assert!(e.contains("`variable.makeTextDynamic`") && e.contains("is not type"), "{e}");
 }
 
+/// Lock Variables refuses defining, deleting and renaming variables, Make … Dynamic included,
+/// while binding, unbinding and the dataset commands still run.
+#[test]
+fn locked_variables_refuse_new_deleted_and_renamed_variables() {
+    let mut s = session();
+    let t = text(&mut s, "Alice");
+    let r = rect(&mut s);
+    s.execute("variable.define", &json!({"name": "Name", "kind": "text"})).unwrap();
+    s.execute("variable.define", &json!({"name": "Show", "kind": "visibility"})).unwrap();
+    assert_eq!(s.execute("variable.list", &json!({})).unwrap()["locked"], false);
+    assert_eq!(s.execute("variable.lock", &json!({})).unwrap()["locked"], true, "without `locked` it toggles");
+    assert_eq!(s.execute("variable.list", &json!({})).unwrap()["locked"], true);
+
+    s.execute("select.set", &json!({"ids": [t.0]})).unwrap();
+    for (cmd, p) in [
+        ("variable.define", json!({"name": "Other", "kind": "text"})),
+        ("variable.delete", json!({"names": ["Name"]})),
+        ("variable.rename", json!({"name": "Name", "newName": "Renamed"})),
+        ("variable.makeTextDynamic", json!({})),
+        ("variable.makeVisibilityDynamic", json!({})),
+    ] {
+        let e = s.execute(cmd, &p).unwrap_err();
+        assert!(matches!(&e, EngineError::Disabled(_, why) if why == "variables are locked"), "{cmd}: {e}");
+    }
+    let names = |s: &mut Session| {
+        s.execute("variable.list", &json!({})).unwrap()["variables"].as_array().unwrap().iter().map(|v| v["name"].clone()).collect::<Vec<_>>()
+    };
+    assert_eq!(names(&mut s), [json!("Name"), json!("Show")], "the variables are as they were");
+
+    // Binding and unbinding still work, and so do the datasets.
+    s.execute("variable.bind", &json!({"variable": "Name", "ids": [t.0]})).unwrap();
+    s.execute("variable.bind", &json!({"variable": "Show", "ids": [r.0]})).unwrap();
+    s.execute("variable.unbind", &json!({"ids": [r.0], "variable": "Show"})).unwrap();
+    s.execute("dataset.capture", &json!({})).unwrap();
+    s.execute("dataset.new", &json!({"name": "Bob", "values": {"Name": "Bob"}})).unwrap();
+    s.execute("dataset.import", &json!({"csv": "name,Name\nCarol,Carol\n"})).unwrap();
+    s.execute("dataset.select", &json!({"name": "Carol"})).unwrap();
+    assert_eq!(plain(&s, t), "Carol");
+
+    // Unlocking lets a variable be defined again; `locked` sets the state rather than toggling.
+    assert_eq!(s.execute("variable.lock", &json!({"locked": false})).unwrap()["locked"], false);
+    assert_eq!(s.execute("variable.lock", &json!({"locked": false})).unwrap()["locked"], false);
+    s.execute("variable.define", &json!({"name": "Other", "kind": "text"})).unwrap();
+}
+
+/// Locking is an undo step only when it changes the state, and the lock is saved with the
+/// document: a file saved locked opens locked, and a file without the key opens unlocked.
+#[test]
+fn the_variables_lock_is_an_undo_step_and_is_saved() {
+    let mut s = session();
+    let steps = |s: &Session| s.doc().unwrap().history.undo.len();
+    let before = steps(&s);
+    s.execute("variable.lock", &json!({"locked": true})).unwrap();
+    assert_eq!(steps(&s), before + 1);
+    s.execute("variable.lock", &json!({"locked": true})).unwrap();
+    assert_eq!(steps(&s), before + 1, "locking locked variables is not a step");
+    assert!(s.doc().unwrap().is_dirty());
+
+    let saved = vectorcraft_format::save(&s.doc().unwrap().doc, false);
+    assert!(vectorcraft_format::load(&saved).unwrap().variables.locked, "a document saved locked opens locked");
+    let mut v: Value = serde_json::from_slice(&saved).unwrap();
+    assert_eq!(v["document"]["variables"]["locked"], true);
+    v["document"]["variables"].as_object_mut().unwrap().remove("locked");
+    assert!(!vectorcraft_format::load(&serde_json::to_vec(&v).unwrap()).unwrap().variables.locked, "a file without the key opens unlocked");
+
+    s.execute("edit.undo", &json!({})).unwrap();
+    assert!(!s.doc().unwrap().doc.variables.locked, "undo unlocks");
+    let v: Value = serde_json::from_slice(&vectorcraft_format::save(&s.doc().unwrap().doc, false)).unwrap();
+    assert!(v["document"].get("variables").is_none_or(|v| v.get("locked").is_none()), "unlocked variables write no key: {v}");
+    s.execute("edit.redo", &json!({})).unwrap();
+    assert!(s.doc().unwrap().doc.variables.locked, "redo locks again");
+}
+
 /// Capture Data Set records what the art holds now, which is how rows are made — the art is
 /// edited and captured, rather than the values typed.
 #[test]
diff --git a/crates/ui-egui/src/i18n/bg.tsv b/crates/ui-egui/src/i18n/bg.tsv
index 567263cfc..2c520f028 100644
--- a/crates/ui-egui/src/i18n/bg.tsv
+++ b/crates/ui-egui/src/i18n/bg.tsv
@@ -3266,6 +3266,8 @@
 	Variables	Променливи
 	New Variable	Нова променлива
 	Delete Variable	Изтриване на променлива
+	Lock Variables	Заключване на променливите
+	Unlock Variables	Отключване на променливите
 	List Variables	Списък с променливи
 	Bind Variable	Свързване на променлива
 	Unbind Variable	Отвързване на променлива
@@ -4046,6 +4048,7 @@ axis	Both	И двете
 @msg	unknown tool or command `{key}`	непознат инструмент или команда `{key}`
 @msg	unknown workspace (one of {_1})	непознато работно пространство (едно от {_1})
 @msg	unsupported: {0}	не се поддържа: {0}
+@msg	variables are locked	променливите са заключени
 @msg	version {0} files can't be compressed: only version {COMPRESSED_SINCE} and later open compressed files	файловете от версия {0} не могат да бъдат компресирани: само версия {COMPRESSED_SINCE} и по-нови отварят компресирани файлове
 @msg	width and height are at least 1 pixel	ширината и височината са най-малко 1 пиксел
 @msg	workspace name can't be empty	името на работното пространство не може да бъде празно
diff --git a/crates/ui-egui/src/i18n/cs.tsv b/crates/ui-egui/src/i18n/cs.tsv
index 73416d3c5..a161b8e64 100644
--- a/crates/ui-egui/src/i18n/cs.tsv
+++ b/crates/ui-egui/src/i18n/cs.tsv
@@ -653,6 +653,8 @@
 	New Variable…	Nová proměnná…
 	Unbind Variable	Zrušit přiřazení proměnné
 	Delete Variable	Odstranit proměnnou
+	Lock Variables	Zamknout proměnné
+	Unlock Variables	Odemknout proměnné
 	New Data Set…	Nová sada dat…
 	Edit Data Set…	Upravit sadu dat…
 	Delete Data Set	Odstranit sadu dat
@@ -4420,6 +4422,7 @@ imageTrace	Outline	Obrys
 @msg	unknown tool or command `{key}`	neznámý nástroj nebo příkaz `{key}`
 @msg	unknown workspace (one of {_1})	neznámý pracovní prostor (jeden z {_1})
 @msg	unsupported: {0}	nepodporováno: {0}
+@msg	variables are locked	proměnné jsou zamčené
 @msg	version {0} files can't be compressed: only version {COMPRESSED_SINCE} and later open compressed files	soubory verze {0} nelze komprimovat: komprimované soubory otevírá až verze {COMPRESSED_SINCE} a novější
 @msg	width and height are at least 1 pixel	šířka i výška jsou alespoň 1 obrazový bod
 @msg	workspace name can't be empty	název pracovního prostoru nesmí být prázdný
diff --git a/crates/ui-egui/src/i18n/de.tsv b/crates/ui-egui/src/i18n/de.tsv
index 802e182d1..0b609d158 100644
--- a/crates/ui-egui/src/i18n/de.tsv
+++ b/crates/ui-egui/src/i18n/de.tsv
@@ -4047,6 +4047,7 @@ theme	Appearance	Erscheinungsbild
 @msg	unknown tool or command `{key}`	unbekanntes Werkzeug oder unbekannter Befehl `{key}`
 @msg	unknown workspace (one of {_1})	unbekannter Arbeitsbereich (einer von {_1})
 @msg	unsupported: {0}	nicht unterstützt: {0}
+@msg	variables are locked	die Variablen sind gesperrt
 @msg	version {0} files can't be compressed: only version {COMPRESSED_SINCE} and later open compressed files	Dateien der Version {0} können nicht komprimiert werden: Erst Version {COMPRESSED_SINCE} und neuer öffnen komprimierte Dateien
 @msg	width and height are at least 1 pixel	Breite und Höhe betragen mindestens 1 Pixel
 @msg	workspace name can't be empty	der Name des Arbeitsbereichs darf nicht leer sein
@@ -4313,6 +4314,8 @@ theme	Appearance	Erscheinungsbild
 	Highlight Variable	Variable hervorheben
 	New Variable	Neue Variable
 	Delete Variable	Variable löschen
+	Lock Variables	Variablen sperren
+	Unlock Variables	Variablen entsperren
 	List Variables	Variablen auflisten
 	Bind Variable	Variable binden
 	Unbind Variable	Variable lösen
diff --git a/crates/ui-egui/src/i18n/el.tsv b/crates/ui-egui/src/i18n/el.tsv
index b6528bebb..6c4e23cc1 100644
--- a/crates/ui-egui/src/i18n/el.tsv
+++ b/crates/ui-egui/src/i18n/el.tsv
@@ -3580,6 +3580,8 @@ theme	Appearance	Εμφάνιση
 	Variable Width Profile	Προφίλ μεταβλητού πλάτους
 	New Variable	Νέα μεταβλητή
 	Delete Variable	Διαγραφή μεταβλητής
+	Lock Variables	Κλείδωμα μεταβλητών
+	Unlock Variables	Ξεκλείδωμα μεταβλητών
 	List Variables	Λίστα μεταβλητών
 	Bind Variable	Σύνδεση μεταβλητής
 	Unbind Variable	Αποσύνδεση μεταβλητής
@@ -4097,6 +4099,7 @@ theme	Appearance	Εμφάνιση
 @msg	unknown tool or command `{key}`	άγνωστο εργαλείο ή εντολή `{key}`
 @msg	unknown workspace (one of {_1})	άγνωστος χώρος εργασίας (ένας από τους {_1})
 @msg	unsupported: {0}	δεν υποστηρίζεται: {0}
+@msg	variables are locked	οι μεταβλητές είναι κλειδωμένες
 @msg	version {0} files can't be compressed: only version {COMPRESSED_SINCE} and later open compressed files	τα αρχεία έκδοσης {0} δεν μπορούν να συμπιεστούν: μόνο η έκδοση {COMPRESSED_SINCE} και νεότερες ανοίγουν συμπιεσμένα αρχεία
 @msg	width and height are at least 1 pixel	το πλάτος και το ύψος πρέπει να είναι τουλάχιστον 1 εικονοστοιχείο
 @msg	workspace name can't be empty	το όνομα χώρου εργασίας δεν μπορεί να είναι κενό
diff --git a/crates/ui-egui/src/i18n/es.tsv b/crates/ui-egui/src/i18n/es.tsv
index 61be275b3..1f3a92f02 100644
--- a/crates/ui-egui/src/i18n/es.tsv
+++ b/crates/ui-egui/src/i18n/es.tsv
@@ -3325,6 +3325,8 @@
 	Variables	Variables
 	New Variable	Nueva variable
 	Delete Variable	Eliminar variable
+	Lock Variables	Bloquear variables
+	Unlock Variables	Desbloquear variables
 	List Variables	Enumerar variables
 	Bind Variable	Vincular variable
 	Unbind Variable	Desvincular variable
@@ -4121,6 +4123,7 @@ axis	Both	Ambos
 @msg	unknown tool or command `{key}`	herramienta o comando desconocido `{key}`
 @msg	unknown workspace (one of {_1})	espacio de trabajo desconocido (uno de estos: {_1})
 @msg	unsupported: {0}	no compatible: {0}
+@msg	variables are locked	las variables están bloqueadas
 @msg	version {0} files can't be compressed: only version {COMPRESSED_SINCE} and later open compressed files	los archivos de la versión {0} no se pueden comprimir: solo la versión {COMPRESSED_SINCE} y posteriores abren archivos comprimidos
 @msg	width and height are at least 1 pixel	el ancho y el alto son de al menos 1 píxel
 @msg	workspace name can't be empty	el nombre del espacio de trabajo no puede estar vacío
diff --git a/crates/ui-egui/src/i18n/fi.tsv b/crates/ui-egui/src/i18n/fi.tsv
index a3a6e7902..c7031c834 100644
--- a/crates/ui-egui/src/i18n/fi.tsv
+++ b/crates/ui-egui/src/i18n/fi.tsv
@@ -644,6 +644,8 @@
 	New Variable…	Uusi muuttuja…
 	Unbind Variable	Pura muuttujan sidonta
 	Delete Variable	Poista muuttuja
+	Lock Variables	Lukitse muuttujat
+	Unlock Variables	Avaa muuttujien lukitus
 	New Data Set…	Uusi tietojoukko…
 	Edit Data Set…	Muokkaa tietojoukkoa…
 	Delete Data Set	Poista tietojoukko
@@ -4342,6 +4344,7 @@ imageTrace	Outline	Ääriviiva
 @msg	unknown tool or command `{key}`	tuntematon työkalu tai komento `{key}`
 @msg	unknown workspace (one of {_1})	tuntematon työtila (jokin seuraavista: {_1})
 @msg	unsupported: {0}	ei tuettu: {0}
+@msg	variables are locked	muuttujat on lukittu
 @msg	version {0} files can't be compressed: only version {COMPRESSED_SINCE} and later open compressed files	version {0} tiedostoja ei voi pakata: pakattuja tiedostoja voi avata vain versiosta {COMPRESSED_SINCE} alkaen
 @msg	width and height are at least 1 pixel	leveys ja korkeus ovat vähintään 1 pikseli
 @msg	workspace name can't be empty	työtilan nimi ei voi olla tyhjä
diff --git a/crates/ui-egui/src/i18n/fr.tsv b/crates/ui-egui/src/i18n/fr.tsv
index bf3205141..af97d9c54 100644
--- a/crates/ui-egui/src/i18n/fr.tsv
+++ b/crates/ui-egui/src/i18n/fr.tsv
@@ -3322,6 +3322,8 @@
 	Variables	Variables
 	New Variable	Nouvelle variable
 	Delete Variable	Supprimer la variable
+	Lock Variables	Verrouiller les variables
+	Unlock Variables	Déverrouiller les variables
 	List Variables	Lister les variables
 	Bind Variable	Lier la variable
 	Unbind Variable	Délier la variable
@@ -4118,6 +4120,7 @@ axis	Both	Les deux
 @msg	unknown tool or command `{key}`	outil ou commande inconnu `{key}`
 @msg	unknown workspace (one of {_1})	espace de travail inconnu (valeurs possibles : {_1})
 @msg	unsupported: {0}	non pris en charge : {0}
+@msg	variables are locked	les variables sont verrouillées
 @msg	version {0} files can't be compressed: only version {COMPRESSED_SINCE} and later open compressed files	les fichiers de version {0} ne peuvent pas être compressés : seules les versions {COMPRESSED_SINCE} et ultérieures ouvrent les fichiers compressés
 @msg	width and height are at least 1 pixel	la largeur et la hauteur valent au moins 1 pixel
 @msg	workspace name can't be empty	le nom de l’espace de travail ne peut pas être vide
diff --git a/crates/ui-egui/src/i18n/hu.tsv b/crates/ui-egui/src/i18n/hu.tsv
index efabf2eef..6a829c0c2 100644
--- a/crates/ui-egui/src/i18n/hu.tsv
+++ b/crates/ui-egui/src/i18n/hu.tsv
@@ -2093,6 +2093,7 @@ file-filter	Templates	Sablonok
 	Lock Others	Többi zárolása
 	Lock Slices	Szeletek zárolása
 	Lock Station Point	Nézőpont zárolása
+	Lock Variables	Változók zárolása
 	Logo 1000×1000	Logó 1000×1000
 	Long Lines	Hosszú vonalak
 	Long Strokes	Hosszú vonások
@@ -3956,6 +3957,7 @@ mark-style	Japanese	Japán
 	Unlock All Layers	Összes réteg zárolásának feloldása
 	Unlock Grid	Rács zárolásának feloldása
 	Unlock Guides	Segédvonalak zárolásának feloldása
+	Unlock Variables	Változók zárolásának feloldása
 	Unnamed Objects	Névtelen objektumok
 	Unprintable margin:	Nem nyomtatható margó:
 	Unsharp Mask	Életlenítő maszk
@@ -4841,6 +4843,7 @@ imageTrace	Outline	Körvonal
 @msg	unsupported: {0}	nem támogatott: {0}
 @msg	Updated {_1} image(s)	Frissített képek: {_1}
 @msg	Updated {_1} linked file(s) changed on disk	Frissített, a lemezen módosult csatolt fájlok: {_1}
+@msg	variables are locked	a változók zárolva vannak
 @msg	VectorCraft doesn't search other apps' or the system's folders: {path}	a VectorCraft nem keres más alkalmazások és a rendszer mappáiban: {path}
 @msg	VectorCraft doesn't search the Shared or Public folder in Users: {path}	a VectorCraft nem keres a Users alatti Shared és Public mappában: {path}
 @msg	VectorCraft failed to start: {e}	A VectorCraft nem tudott elindulni: {e}
diff --git a/crates/ui-egui/src/i18n/it.tsv b/crates/ui-egui/src/i18n/it.tsv
index 87f94d523..b387698f0 100644
--- a/crates/ui-egui/src/i18n/it.tsv
+++ b/crates/ui-egui/src/i18n/it.tsv
@@ -3345,6 +3345,8 @@ mark-style	Japanese	Giapponese
 	Variables	Variabili
 	New Variable	Nuova variabile
 	Delete Variable	Elimina variabile
+	Lock Variables	Blocca variabili
+	Unlock Variables	Sblocca variabili
 	List Variables	Elenca variabili
 	Bind Variable	Collega variabile
 	Unbind Variable	Scollega variabile
@@ -4146,6 +4148,7 @@ axis	Both	Entrambi
 @msg	unknown tool or command `{key}`	strumento o comando sconosciuto `{key}`
 @msg	unknown workspace (one of {_1})	area di lavoro sconosciuta (una delle seguenti: {_1})
 @msg	unsupported: {0}	non supportato: {0}
+@msg	variables are locked	le variabili sono bloccate
 @msg	version {0} files can't be compressed: only version {COMPRESSED_SINCE} and later open compressed files	i file della versione {0} non possono essere compressi: solo la versione {COMPRESSED_SINCE} e successive aprono file compressi
 @msg	width and height are at least 1 pixel	larghezza e altezza sono di almeno 1 pixel
 @msg	workspace name can't be empty	il nome dell'area di lavoro non può essere vuoto
diff --git a/crates/ui-egui/src/i18n/ja.tsv b/crates/ui-egui/src/i18n/ja.tsv
index f903169bd..f99af9c01 100644
--- a/crates/ui-egui/src/i18n/ja.tsv
+++ b/crates/ui-egui/src/i18n/ja.tsv
@@ -615,6 +615,8 @@
 	Variables	変数
 	New Variable	新規変数
 	Delete Variable	変数を削除
+	Lock Variables	変数をロック
+	Unlock Variables	変数をロック解除
 	List Variables	変数一覧
 	Bind Variable	変数をバインド
 	Unbind Variable	変数のバインドを解除
@@ -3769,6 +3771,7 @@ swatch	Bright Violet	ビビッドバイオレット
 @msg	{command} didn't create an object	{command} でオブジェクトが作成されませんでした
 @msg	Make Guides: select paths	ガイドを作成: パスを選択してください
 @msg	Release Guides: no guides	ガイドを解除: ガイドがありません
+@msg	variables are locked	変数がロックされています
 @msg	guides are locked	ガイドがロックされています
 @msg	handle must be in or out	handle には in または out を指定してください
 @msg	no saved selection recalled	保存した選択範囲を呼び出していません
diff --git a/crates/ui-egui/src/i18n/ko.tsv b/crates/ui-egui/src/i18n/ko.tsv
index d0d967763..93dd5e233 100644
--- a/crates/ui-egui/src/i18n/ko.tsv
+++ b/crates/ui-egui/src/i18n/ko.tsv
@@ -613,6 +613,8 @@
 	Variables	변수
 	New Variable	새 변수
 	Delete Variable	변수 삭제
+	Lock Variables	변수 잠그기
+	Unlock Variables	변수 잠금 해제
 	List Variables	변수 목록
 	Bind Variable	변수 연결
 	Unbind Variable	변수 연결 해제
@@ -3701,6 +3703,7 @@ theme	Appearance	외관
 @msg	{command} didn't create an object	{command}이(가) 개체를 만들지 않았습니다
 @msg	Make Guides: select paths	안내선 만들기: 패스를 선택하세요
 @msg	Release Guides: no guides	안내선 해제: 안내선이 없습니다
+@msg	variables are locked	변수가 잠겨 있습니다
 @msg	guides are locked	안내선이 잠겨 있습니다
 @msg	handle must be in or out	handle은 in 또는 out이어야 합니다
 @msg	no saved selection recalled	불러온 저장된 선택 영역이 없습니다
diff --git a/crates/ui-egui/src/i18n/pl.tsv b/crates/ui-egui/src/i18n/pl.tsv
index f680fe99e..c24a2da14 100644
--- a/crates/ui-egui/src/i18n/pl.tsv
+++ b/crates/ui-egui/src/i18n/pl.tsv
@@ -601,6 +601,8 @@
 	New Variable…	Nowa zmienna…
 	Unbind Variable	Odłącz zmienną
 	Delete Variable	Usuń zmienną
+	Lock Variables	Zablokuj zmienne
+	Unlock Variables	Odblokuj zmienne
 	New Data Set…	Nowy zestaw danych…
 	Edit Data Set…	Edytuj zestaw danych…
 	Delete Data Set	Usuń zestaw danych
@@ -4239,6 +4241,7 @@ imageTrace	Outline	Kontur
 @msg	unknown tool or command `{key}`	nieznane narzędzie lub polecenie `{key}`
 @msg	unknown workspace (one of {_1})	nieznany obszar roboczy (jeden z: {_1})
 @msg	unsupported: {0}	nieobsługiwane: {0}
+@msg	variables are locked	zmienne są zablokowane
 @msg	version {0} files can't be compressed: only version {COMPRESSED_SINCE} and later open compressed files	plików w wersji {0} nie można kompresować: skompresowane pliki otwierają tylko wersje {COMPRESSED_SINCE} i nowsze
 @msg	width and height are at least 1 pixel	szerokość i wysokość muszą wynosić co najmniej 1 piksel
 @msg	workspace name can't be empty	nazwa obszaru roboczego nie może być pusta
diff --git a/crates/ui-egui/src/i18n/pt-br.tsv b/crates/ui-egui/src/i18n/pt-br.tsv
index 18c98489f..95ed680fd 100644
--- a/crates/ui-egui/src/i18n/pt-br.tsv
+++ b/crates/ui-egui/src/i18n/pt-br.tsv
@@ -2711,6 +2711,8 @@
 	New Variable…	Nova variável…
 	Unbind Variable	Desassociar variável
 	Delete Variable	Excluir variável
+	Lock Variables	Bloquear variáveis
+	Unlock Variables	Desbloquear variáveis
 	New Data Set…	Novo conjunto de dados…
 	Edit Data Set…	Editar conjunto de dados…
 	Delete Data Set	Excluir conjunto de dados
@@ -3702,6 +3704,7 @@ axis	Both	Ambos
 @msg	unknown tool or command `{key}`	ferramenta ou comando desconhecido `{key}`
 @msg	unknown workspace (one of {_1})	espaço de trabalho desconhecido (um de {_1})
 @msg	unsupported: {0}	não suportado: {0}
+@msg	variables are locked	as variáveis estão bloqueadas
 @msg	version {0} files can't be compressed: only version {COMPRESSED_SINCE} and later open compressed files	arquivos da versão {0} não podem ser compactados: somente a versão {COMPRESSED_SINCE} e posteriores abrem arquivos compactados
 @msg	width and height are at least 1 pixel	largura e altura têm pelo menos 1 pixel
 @msg	workspace name can't be empty	o nome do espaço de trabalho não pode estar vazio
diff --git a/crates/ui-egui/src/i18n/ru.tsv b/crates/ui-egui/src/i18n/ru.tsv
index 473985077..d3e70d532 100644
--- a/crates/ui-egui/src/i18n/ru.tsv
+++ b/crates/ui-egui/src/i18n/ru.tsv
@@ -3341,6 +3341,8 @@ mark-style	Japanese	Японский
 	Variables	Переменные
 	New Variable	Новая переменная
 	Delete Variable	Удалить переменную
+	Lock Variables	Заблокировать переменные
+	Unlock Variables	Разблокировать переменные
 	List Variables	Перечислить переменные
 	Bind Variable	Привязать переменную
 	Unbind Variable	Отвязать переменную
@@ -4142,6 +4144,7 @@ axis	Both	Оба
 @msg	unknown tool or command `{key}`	неизвестный инструмент или команда `{key}`
 @msg	unknown workspace (one of {_1})	неизвестная рабочая среда (одна из: {_1})
 @msg	unsupported: {0}	не поддерживается: {0}
+@msg	variables are locked	переменные заблокированы
 @msg	version {0} files can't be compressed: only version {COMPRESSED_SINCE} and later open compressed files	файлы версии {0} не могут быть сжаты: только версия {COMPRESSED_SINCE} и новее открывают сжатые файлы
 @msg	width and height are at least 1 pixel	ширина и высота должны быть не менее 1 пикселя
 @msg	workspace name can't be empty	имя рабочей среды не может быть пустым
diff --git a/crates/ui-egui/src/i18n/sv.tsv b/crates/ui-egui/src/i18n/sv.tsv
index d09d3b30d..d0cf60a70 100644
--- a/crates/ui-egui/src/i18n/sv.tsv
+++ b/crates/ui-egui/src/i18n/sv.tsv
@@ -3266,6 +3266,8 @@
 	Variables	Variabler
 	New Variable	Ny variabel
 	Delete Variable	Radera variabel
+	Lock Variables	Lås variabler
+	Unlock Variables	Lås upp variabler
 	List Variables	Lista variabler
 	Bind Variable	Bind variabel
 	Unbind Variable	Koppla bort variabel
@@ -4045,6 +4047,7 @@ axis	Both	Båda
 @msg	unknown tool or command `{key}`	okänt verktyg eller kommando `{key}`
 @msg	unknown workspace (one of {_1})	okänd arbetsyta (en av {_1})
 @msg	unsupported: {0}	stöds inte: {0}
+@msg	variables are locked	variablerna är låsta
 @msg	version {0} files can't be compressed: only version {COMPRESSED_SINCE} and later open compressed files	filer i version {0} kan inte komprimeras: endast version {COMPRESSED_SINCE} och senare kan öppna komprimerade filer
 @msg	width and height are at least 1 pixel	bredd och höjd är minst 1 pixel
 @msg	workspace name can't be empty	arbetsytans namn får inte vara tomt
diff --git a/crates/ui-egui/src/i18n/uk.tsv b/crates/ui-egui/src/i18n/uk.tsv
index bf4c2c3ef..c8344f116 100644
--- a/crates/ui-egui/src/i18n/uk.tsv
+++ b/crates/ui-egui/src/i18n/uk.tsv
@@ -3338,6 +3338,8 @@ effect	Points	Точки
 	Variables	Змінні
 	New Variable	Нова змінна
 	Delete Variable	Видалити змінну
+	Lock Variables	Заблокувати змінні
+	Unlock Variables	Розблокувати змінні
 	List Variables	Перерахувати змінні
 	Bind Variable	Прив'язати змінну
 	Unbind Variable	Відв'язати змінну
@@ -4130,6 +4132,7 @@ axis	Both	Обидві
 @msg	unknown tool or command `{key}`	невідомий інструмент або команда `{key}`
 @msg	unknown workspace (one of {_1})	невідоме робоче середовище (одна з: {_1})
 @msg	unsupported: {0}	не підтримується: {0}
+@msg	variables are locked	змінні заблоковані
 @msg	version {0} files can't be compressed: only version {COMPRESSED_SINCE} and later open compressed files	файли версії {0} не можуть бути стиснуті: тільки версія {COMPRESSED_SINCE} і новіші відкривають стислі файли
 @msg	width and height are at least 1 pixel	ширина та висота повинні бути не менше 1 пікселя
 @msg	workspace name can't be empty	ім’я робочого середовища не може бути порожнім
diff --git a/crates/ui-egui/src/i18n/vi.tsv b/crates/ui-egui/src/i18n/vi.tsv
index 1c7209bc6..6a870d46d 100644
--- a/crates/ui-egui/src/i18n/vi.tsv
+++ b/crates/ui-egui/src/i18n/vi.tsv
@@ -1903,6 +1903,7 @@ file-filter	Templates	Mẫu
 	Lock Others	Khóa các mục khác
 	Lock Slices	Khóa lát cắt
 	Lock Station Point	Khóa điểm trạm
+	Lock Variables	Khóa biến số
 	Long Lines	Nét dài
 	Long Strokes	Nét vẽ dài
 	Longest:	Dài nhất:
@@ -3634,6 +3635,7 @@ mark-style	Japanese	Kiểu Nhật
 	Unlock All Layers	Mở khóa tất cả lớp
 	Unlock Grid	Mở khóa lưới
 	Unlock Guides	Mở khóa đường căn
+	Unlock Variables	Mở khóa biến số
 	Unnamed Objects	Đối tượng chưa đặt tên
 	Unprintable margin:	Lề không in được:
 	Unsharp Mask	Tăng độ sắc nét
@@ -4485,6 +4487,7 @@ theme	Appearance	Giao diện
 @msg	unsupported: {0}	không được hỗ trợ: {0}
 @msg	Updated {_1} image(s)	Đã cập nhật {_1} ảnh
 @msg	Updated {_1} linked file(s) changed on disk	Đã cập nhật {_1} tệp liên kết đã thay đổi trên đĩa
+@msg	variables are locked	biến số bị khóa
 @msg	VectorCraft doesn't search other apps' or the system's folders: {path}	VectorCraft không tìm kiếm trong thư mục của ứng dụng khác hoặc hệ thống: {path}
 @msg	VectorCraft doesn't search the Shared or Public folder in Users: {path}	VectorCraft không tìm kiếm thư mục Shared hoặc Public trong Users: {path}
 @msg	VectorCraft failed to start: {e}	VectorCraft khởi động thất bại: {e}
diff --git a/crates/ui-egui/src/i18n/zh-hans.tsv b/crates/ui-egui/src/i18n/zh-hans.tsv
index 2f45a416e..6a306bf0c 100644
--- a/crates/ui-egui/src/i18n/zh-hans.tsv
+++ b/crates/ui-egui/src/i18n/zh-hans.tsv
@@ -3204,6 +3204,9 @@ mark-style	Japanese	日式
 	Variables	变量
 	New Variable	新建变量
 	Delete Variable	删除变量
+	Lock Variables	锁定变量
+	Unlock Variables	解锁变量
+@msg	variables are locked	变量已锁定
 	List Variables	列出变量
 	Bind Variable	绑定变量
 	Unbind Variable	解除变量绑定
diff --git a/crates/ui-egui/src/i18n/zh-hant.tsv b/crates/ui-egui/src/i18n/zh-hant.tsv
index 15cebb0e8..57c5e9436 100644
--- a/crates/ui-egui/src/i18n/zh-hant.tsv
+++ b/crates/ui-egui/src/i18n/zh-hant.tsv
@@ -3325,6 +3325,8 @@ mark-style	Japanese	日式
 	Variables	變數
 	New Variable	新增變數
 	Delete Variable	刪除變數
+	Lock Variables	鎖定變數
+	Unlock Variables	解除鎖定變數
 	List Variables	列出變數
 	Bind Variable	綁定變數
 	Unbind Variable	解除變數綁定
diff --git a/crates/ui-egui/src/panels/variables.rs b/crates/ui-egui/src/panels/variables.rs
index a256e10af..96f32e132 100644
--- a/crates/ui-egui/src/panels/variables.rs
+++ b/crates/ui-egui/src/panels/variables.rs
@@ -136,6 +136,8 @@ pub fn show(app: &mut VectorcraftApp, ui: &mut Ui) {
     let active = sets.iter().find(|s| s.active);
     let Picked { selected, has_selection, selection_bound, single_type, single_image, selection_graph } = picked(st);
     let highlighted = highlighted_row(st);
+    // Lock Variables: no variable is defined, deleted or renamed until they are unlocked.
+    let locked = st.doc.variables.locked;
 
     // The current data set across the top: its name, and the arrows that step through them.
     ui.horizontal(|ui| {
@@ -181,7 +183,7 @@ pub fn show(app: &mut VectorcraftApp, ui: &mut Ui) {
             if r.clicked() {
                 click_row(app, &row.name, &row.bound);
             }
-            if r.double_clicked() {
+            if r.double_clicked() && !locked {
                 crate::dialogs::variables::open(app, "variable.rename", Some(&row.name));
             }
         });
@@ -204,31 +206,37 @@ pub fn show(app: &mut VectorcraftApp, ui: &mut Ui) {
         }
     }
 
-    // The bottom bar: make the selection dynamic, and define and delete what the lists show.
+    // The bottom bar: make the selection dynamic, define and delete what the lists show, and
+    // lock the variables.
     ui.separator();
     ui.horizontal(|ui| {
-        if widgets::icon_button_enabled(ui, "type", tl!("Make Text Dynamic"), false, single_type, 24.0).clicked() {
+        if widgets::icon_button_enabled(ui, "type", tl!("Make Text Dynamic"), false, single_type && !locked, 24.0).clicked() {
             app.run("variable.makeTextDynamic", json!({})).ok();
         }
-        if widgets::icon_button_enabled(ui, "eye", tl!("Make Visibility Dynamic"), false, has_selection, 24.0).clicked() {
+        if widgets::icon_button_enabled(ui, "eye", tl!("Make Visibility Dynamic"), false, has_selection && !locked, 24.0).clicked() {
             app.run("variable.makeVisibilityDynamic", json!({})).ok();
         }
-        if widgets::icon_button_enabled(ui, "image", tl!("Make Image Dynamic"), false, single_image, 24.0).clicked() {
+        if widgets::icon_button_enabled(ui, "image", tl!("Make Image Dynamic"), false, single_image && !locked, 24.0).clicked() {
             app.run("variable.makeImageDynamic", json!({})).ok();
         }
-        if widgets::icon_button_enabled(ui, "chart-column", tl!("Make Graph Dynamic"), false, selection_graph, 24.0).clicked() {
+        if widgets::icon_button_enabled(ui, "chart-column", tl!("Make Graph Dynamic"), false, selection_graph && !locked, 24.0).clicked() {
             app.run("variable.makeGraphDynamic", json!({})).ok();
         }
-        if widgets::icon_button(ui, "plus", tl!("New Variable…"), false, 24.0).clicked() {
+        if widgets::icon_button_enabled(ui, "plus", tl!("New Variable…"), false, !locked, 24.0).clicked() {
             crate::menus::invoke(app, "variable.define", json!({}));
         }
         if widgets::icon_button_enabled(ui, "link-2-off", tl!("Unbind Variable"), false, selection_bound, 24.0).clicked() {
             app.run("variable.unbind", json!({"ids": selected})).ok();
         }
         // The bin deletes the highlighted variable only, as the reference panel's does.
-        if widgets::icon_button_enabled(ui, "trash-2", tl!("Delete Variable"), false, highlighted.is_some(), 24.0).clicked() {
+        if widgets::icon_button_enabled(ui, "trash-2", tl!("Delete Variable"), false, highlighted.is_some() && !locked, 24.0).clicked() {
             delete_highlighted(app);
         }
+        // The lock button is drawn pressed while the variables are locked.
+        let tip = if locked { tl!("Unlock Variables") } else { tl!("Lock Variables") };
+        if widgets::icon_button(ui, "lock", tip, locked, 24.0).clicked() {
+            app.run("variable.lock", json!({})).ok();
+        }
     });
     ui.horizontal(|ui| {
         // Capture records what the art holds now as a new row (paste: take it in); Update
@@ -254,33 +262,38 @@ pub fn menu(app: &mut VectorcraftApp, ui: &mut Ui) {
     let highlighted = highlighted_row(st);
     let highlighted_bound: Vec<u64> = highlighted.as_ref().map(|h| bound_objects(st, h)).unwrap_or_default();
     let Picked { selected, has_selection, selection_bound, single_type, single_image, selection_graph } = picked(st);
+    let locked = st.doc.variables.locked;
 
-    if widgets::menu_item(ui, tl!("New Variable…"), true, false) {
+    if widgets::menu_item(ui, tl!("New Variable…"), !locked, false) {
         crate::menus::invoke(app, "variable.define", json!({}));
     }
     // Variable Options renames the highlighted variable, else the first.
-    if widgets::menu_item(ui, tl!("Variable Options…"), !vars.is_empty(), false) {
+    if widgets::menu_item(ui, tl!("Variable Options…"), !vars.is_empty() && !locked, false) {
         let name = highlighted.clone().or_else(|| vars.first().cloned()).unwrap_or_default();
         crate::dialogs::variables::open(app, "variable.rename", Some(&name));
     }
-    if widgets::menu_item(ui, tl!("Make Text Dynamic"), single_type, false) {
+    if widgets::menu_item(ui, tl!("Make Text Dynamic"), single_type && !locked, false) {
         app.run("variable.makeTextDynamic", json!({})).ok();
     }
-    if widgets::menu_item(ui, tl!("Make Visibility Dynamic"), has_selection, false) {
+    if widgets::menu_item(ui, tl!("Make Visibility Dynamic"), has_selection && !locked, false) {
         app.run("variable.makeVisibilityDynamic", json!({})).ok();
     }
-    if widgets::menu_item(ui, tl!("Make Image Dynamic"), single_image, false) {
+    if widgets::menu_item(ui, tl!("Make Image Dynamic"), single_image && !locked, false) {
         app.run("variable.makeImageDynamic", json!({})).ok();
     }
-    if widgets::menu_item(ui, tl!("Make Graph Dynamic"), selection_graph, false) {
+    if widgets::menu_item(ui, tl!("Make Graph Dynamic"), selection_graph && !locked, false) {
         app.run("variable.makeGraphDynamic", json!({})).ok();
     }
     if widgets::menu_item(ui, tl!("Unbind Variable"), selection_bound, false) {
         app.run("variable.unbind", json!({"ids": selected})).ok();
     }
-    if widgets::menu_item(ui, tl!("Delete Variable"), highlighted.is_some(), false) {
+    if widgets::menu_item(ui, tl!("Delete Variable"), highlighted.is_some() && !locked, false) {
         delete_highlighted(app);
     }
+    let lock = if locked { tl!("Unlock Variables") } else { tl!("Lock Variables") };
+    if widgets::menu_item(ui, lock, true, false) {
+        app.run("variable.lock", json!({})).ok();
+    }
     ui.separator();
     if widgets::menu_item(ui, tl!("Capture Data Set"), true, false) {
         app.run("dataset.capture", json!({})).ok();
@@ -398,6 +411,20 @@ mod tests {
         }
     }
 
+    /// The panel menu offers Lock Variables, and Unlock Variables once they are locked.
+    #[test]
+    fn the_panel_menu_locks_and_unlocks_the_variables() {
+        let mut app = app_with_data();
+        let text = crate::tests_labels::painted_text(&mut app, menu);
+        assert!(text.contains("Lock Variables") && !text.contains("Unlock Variables"), "{text}");
+        app.run("variable.lock", json!({})).unwrap();
+        let text = crate::tests_labels::painted_text(&mut app, menu);
+        assert!(text.contains("Unlock Variables"), "{text}");
+        // The panel still draws while they are locked.
+        let text = crate::tests_labels::painted_text(&mut app, show);
+        assert!(text.contains("Name") && text.contains("Data Set 1"), "{text}");
+    }
+
     /// What the panel acts on is the highlight, and only while it names a variable: a stale one
     /// (deleted elsewhere, undone) highlights nothing, so Delete and Options… stay disabled.
     #[test]
diff --git a/docs/mcp.md b/docs/mcp.md
index fe4fdd0f5..c48f2b99b 100644
--- a/docs/mcp.md
+++ b/docs/mcp.md
@@ -1125,7 +1125,11 @@ already walks Image Trace. Short agent entry points:
 - Variables: `variable.list`, `variable.define {name, kind: text|visibility|image|graph}`, `variable.bind {variable, ids?}`,
   `variable.makeTextDynamic`, `variable.makeVisibilityDynamic`, `variable.makeImageDynamic`, `variable.makeGraphDynamic`,
   `variable.unbind`, `variable.rename`, `variable.delete`, `variable.highlight` (image values are file paths, graph
-  values CSV as `graph.setData`).
+  values CSV as `graph.setData`). `variable.lock {locked?}` (Lock Variables) locks or unlocks the variables;
+  without `locked` it toggles, and the lock is saved with the document. While the variables are locked,
+  `variable.define`, `variable.delete`, `variable.rename` and the four `variable.make…Dynamic` commands fail with
+  "variables are locked"; `variable.bind`, `variable.unbind` and the `dataset.*` commands still run, and
+  `variable.list` reports `locked`.
 - Data sets: `dataset.list`, `dataset.new {name, values?}`, `dataset.set {name, values?}`, `dataset.rename`,
   `dataset.delete`, `dataset.capture`, `dataset.update`, `dataset.select {name}`, `dataset.next` /
   `dataset.prev` (each `dataset.select` / next / prev is one undo step over every bound object), `dataset.import {path|data|dataBase64|csv}` /
diff --git a/docs/target-app-parity.md b/docs/target-app-parity.md
index a227243e9..924811581 100644
--- a/docs/target-app-parity.md
+++ b/docs/target-app-parity.md
@@ -425,6 +425,7 @@ Moved from the ROADMAP's "Shipped so far" on 2026-10-10. Update it when a featur
   - Variables: Update Data Set writes what the art holds into the active data set for the variables that data set holds, and keeps the data set's value for a variable whose objects are locked or inside a locked layer or group; `dataset.update {all: true}` also adds the other variables that the art reports a value for.
   - Variables: `dataset.select`, `dataset.next` and `dataset.prev` rewrite type and apply the other values on hidden objects and in hidden layers and groups, which stay hidden unless a visibility value shows them, so a layer shown later holds the selected data set's text; objects that are locked or in a locked layer or group are skipped.
   - Variables: `dataset.select`, `dataset.next` and `dataset.prev` name the area type and type on a path whose text they rewrote and that doesn't fit, in the reply's `overflow` key, as `text.setText` does.
+  - Variables: Lock Variables (`variable.lock`, in the Variables panel's bottom bar and menu) stops variables from being defined, deleted or renamed until they are unlocked, while objects can still be bound and unbound and data sets still change and apply; the lock is saved with the document.
   - Actions panel (record/playback, persisted), generic parameter dialogs for every "…" command.
   - Batch… over data sets names each file after the document and the data set (`action.batch`). It writes `/`, `\` and `:` in the data set's name as `-`, and adds `-2`, `-3`… to a name an earlier data set used.
   - Variables (data merge): text, visibility and image variables bound to objects (an object may carry several), dataset rows applied in one undo step (`variable.*`, `dataset.*`) from a Variables panel and Window › Variables, with dialogs to define, bind and edit, Make Text/Visibility/Image Dynamic, Capture/Update Data Set, CSV import/export (`dataset.import` / `dataset.export`), and a row in italics when an edit leaves the art not matching it; an image dataset value is a file path and apply keeps the object's bounds; bindings let go of deleted art and locked art is left alone; every command, like the rest, is drivable over MCP and the CLI.