diff --git a/hcie-iced-app/crates/hcie-iced-gui/Cargo.toml b/hcie-iced-app/crates/hcie-iced-gui/Cargo.toml
index 65b51bd..7361398 100644
--- a/hcie-iced-app/crates/hcie-iced-gui/Cargo.toml
+++ b/hcie-iced-app/crates/hcie-iced-gui/Cargo.toml
@@ -3,6 +3,10 @@ name = "hcie-iced-gui"
 version = "0.1.0"
 edition = "2021"
 
+[lib]
+name = "hcie_iced_gui"
+path = "src/lib.rs"
+
 [features]
 default = ["tablet-evdev"]
 tablet-evdev = ["dep:evdev"]
diff --git a/hcie-iced-app/crates/hcie-iced-gui/src/lib.rs b/hcie-iced-app/crates/hcie-iced-gui/src/lib.rs
new file mode 100644
index 0000000..7fb2e91
--- /dev/null
+++ b/hcie-iced-app/crates/hcie-iced-gui/src/lib.rs
@@ -0,0 +1,3 @@
+//! HCIE Iced GUI library — re-exports selection types for integration tests.
+
+pub mod selection;
diff --git a/hcie-iced-app/crates/hcie-iced-gui/tests/selection_test.rs b/hcie-iced-app/crates/hcie-iced-gui/tests/selection_test.rs
new file mode 100644
index 0000000..6fa5bf8
--- /dev/null
+++ b/hcie-iced-app/crates/hcie-iced-gui/tests/selection_test.rs
@@ -0,0 +1,72 @@
+//! Tests for selection types: SelectionTransform, TransformHandle, CropState.
+
+use hcie_iced_gui::selection::{CropState, SelectionTransform, TransformHandle};
+
+#[test]
+fn test_selection_transform_is_empty() {
+    let tr = SelectionTransform {
+        pixels: vec![],
+        width: 0,
+        height: 0,
+        pos: iced::Vector::ZERO,
+        size: iced::Vector::ZERO,
+        rotation: 0.0,
+    };
+    assert!(tr.is_empty());
+}
+
+#[test]
+fn test_selection_transform_with_data() {
+    let tr = SelectionTransform {
+        pixels: vec![255; 100],
+        width: 5,
+        height: 5,
+        pos: iced::Vector::new(10.0, 20.0),
+        size: iced::Vector::new(5.0, 5.0),
+        rotation: 0.0,
+    };
+    assert!(!tr.is_empty());
+}
+
+#[test]
+fn test_crop_state_lifecycle() {
+    let mut crop = CropState::default();
+    assert!(!crop.active);
+    assert!(crop.rect.is_none());
+
+    crop.start_drag(10.0, 10.0);
+    assert!(crop.active);
+    assert!(crop.is_dragging);
+
+    crop.update_drag(100.0, 100.0);
+    assert!(crop.rect.is_some());
+    let (x, y, w, h) = crop.rect.unwrap();
+    assert_eq!(x, 10.0);
+    assert_eq!(y, 10.0);
+    assert_eq!(w, 90.0);
+    assert_eq!(h, 90.0);
+
+    crop.end_drag();
+    assert!(!crop.is_dragging);
+
+    let result = crop.confirm();
+    assert!(result.is_some());
+    assert!(!crop.active);
+}
+
+#[test]
+fn test_crop_cancel() {
+    let mut crop = CropState::default();
+    crop.start_drag(10.0, 10.0);
+    crop.update_drag(100.0, 100.0);
+    crop.cancel();
+    assert!(!crop.active);
+    assert!(crop.rect.is_none());
+}
+
+#[test]
+fn test_transform_handle_cursor_hints() {
+    assert_eq!(TransformHandle::Move.cursor_hint(), "move");
+    assert_eq!(TransformHandle::TopLeft.cursor_hint(), "nwse-resize");
+    assert_eq!(TransformHandle::Rotate.cursor_hint(), "crosshair");
+}