diff --git a/src/lib/core/EntityAdmin.h b/src/lib/core/EntityAdmin.h
index bdf70d4..a5772ff 100644
--- a/src/lib/core/EntityAdmin.h
+++ b/src/lib/core/EntityAdmin.h
@@ -28,7 +28,7 @@ public:
     void forEach(Func&& f) const;
 
     template <typename... Ts>
-    bool hasAll(entt::entity entity);
+    bool hasAll(entt::entity entity) const;
 
     template <typename T>
     T& get(entt::entity entity);
@@ -101,7 +101,7 @@ void EntityAdmin::forEach(Func&& f) const
 }
 
 template <typename... Ts>
-bool EntityAdmin::hasAll(entt::entity entity)
+bool EntityAdmin::hasAll(entt::entity entity) const
 {
     return m_registry.all_of<Ts...>(entity);
 }
diff --git a/src/ui/SelectionBounds.cpp b/src/ui/SelectionBounds.cpp
index 52c734c..b3ea85a 100644
--- a/src/ui/SelectionBounds.cpp
+++ b/src/ui/SelectionBounds.cpp
@@ -42,7 +42,7 @@ std::optional<QRectF> getBuildingWidgetRect(const FactoryState& state,
     return std::nullopt;
 }
 
-std::optional<QRectF> getActorWidgetRect(EntityAdmin& admin,
+std::optional<QRectF> getActorWidgetRect(const EntityAdmin& admin,
                                          const WorldCoordinates& coordinates,
                                          entt::entity actor)
 {
@@ -68,7 +68,7 @@ std::optional<QRectF> getActorWidgetRect(EntityAdmin& admin,
     return std::nullopt;
 }
 
-std::optional<QRectF> getDebrisWidgetRect(EntityAdmin& admin,
+std::optional<QRectF> getDebrisWidgetRect(const EntityAdmin& admin,
                                           const WorldCoordinates& coordinates,
                                           entt::entity debris)
 {
@@ -82,7 +82,7 @@ std::optional<QRectF> getDebrisWidgetRect(EntityAdmin& admin,
     return QRectF(center.x() - radius, center.y() - radius, 2.0 * radius, 2.0 * radius);
 }
 
-QRect getSelectionWidgetRect(Simulation& sim, const WorldCoordinates& coordinates,
+QRect getSelectionWidgetRect(const Simulation& sim, const WorldCoordinates& coordinates,
                              const std::vector<BuildingId>& buildings,
                              const std::vector<entt::entity>& actors,
                              const std::vector<entt::entity>& debris)
diff --git a/src/ui/SelectionBounds.h b/src/ui/SelectionBounds.h
index 60c34e6..6c34b23 100644
--- a/src/ui/SelectionBounds.h
+++ b/src/ui/SelectionBounds.h
@@ -29,22 +29,20 @@ std::optional<QRectF> getBuildingWidgetRect(const FactoryState& state,
                                             BuildingId id);
 
 // The body of a ship or of a defence station (REQ-UI-ENTITY-CLICK-SELECT): a station's
-// footprint, or the square the ship's triangle is drawn in. The admin is taken by
-// non-const reference only because EntityAdmin::hasAll() is not const; nothing here
-// writes to it.
-std::optional<QRectF> getActorWidgetRect(EntityAdmin& admin,
+// footprint, or the square the ship's triangle is drawn in.
+std::optional<QRectF> getActorWidgetRect(const EntityAdmin& admin,
                                          const WorldCoordinates& coordinates,
                                          entt::entity actor);
 
 // The circle a piece of debris is drawn as (REQ-UI-DEBRIS-CLICK-SELECT).
-std::optional<QRectF> getDebrisWidgetRect(EntityAdmin& admin,
+std::optional<QRectF> getDebrisWidgetRect(const EntityAdmin& admin,
                                           const WorldCoordinates& coordinates,
                                           entt::entity debris);
 
 // The rectangle covering a whole selection -- one object, or the bounding box of all of
 // them (REQ-UI-SELECTION-PANEL). Objects that no longer resolve are skipped; the result
 // is null when none of them does.
-QRect getSelectionWidgetRect(Simulation& sim, const WorldCoordinates& coordinates,
+QRect getSelectionWidgetRect(const Simulation& sim, const WorldCoordinates& coordinates,
                              const std::vector<BuildingId>& buildings,
                              const std::vector<entt::entity>& actors,
                              const std::vector<entt::entity>& debris);