diff --git a/apps/native/src/components/widget/steps/setup-step.test.tsx b/apps/native/src/components/widget/steps/setup-step.test.tsx
new file mode 100644
index 00000000..6ab126ed
--- /dev/null
+++ b/apps/native/src/components/widget/steps/setup-step.test.tsx
@@ -0,0 +1,72 @@
+import "@testing-library/jest-dom";
+import { fireEvent, render, screen } from "@testing-library/react";
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+import { useWidgetStore } from "@/stores/widget-store";
+import { SetupStep } from "./setup-step";
+
+const mockSaveHost = vi.hoisted(() => vi.fn<(host: string) => Promise<void>>());
+
+vi.mock("@/lib/env", () => ({
+  settings: {
+    NIX_INSTALLED_OVERRIDE: false,
+  },
+}));
+
+vi.mock("@/hooks/use-darwin-config", () => ({
+  useDarwinConfig: () => ({
+    saveHost: mockSaveHost,
+  }),
+}));
+
+vi.mock("@/components/widget/controls/directory-picker", () => ({
+  DirectoryPicker: ({ label }: { label: string }) => (
+    <div data-testid="directory-picker">{label}</div>
+  ),
+}));
+
+vi.mock("@/components/widget/controls/bootstrap-config", () => ({
+  BootstrapConfig: ({ label }: { label: string }) => (
+    <div data-testid="bootstrap-config">{label}</div>
+  ),
+}));
+
+function resetStore() {
+  const store = useWidgetStore.getState();
+  store.setConfigDir("");
+  store.setHosts([]);
+  store.setHost("");
+  store.setError(null);
+  store.setBootstrapping(false);
+}
+
+describe("<SetupStep>", () => {
+  beforeEach(() => {
+    mockSaveHost.mockReset();
+    resetStore();
+  });
+
+  it("persists the displayed host when Next is clicked without changing the dropdown", async () => {
+    const store = useWidgetStore.getState();
+    store.setConfigDir("/Users/me/.darwin");
+    store.setHosts(["mbp"]);
+    store.setHost("mbp");
+
+    render(<SetupStep />);
+
+    fireEvent.click(await screen.findByRole("button", { name: "Next" }));
+
+    expect(mockSaveHost).toHaveBeenCalledWith("mbp");
+    expect(mockSaveHost).not.toHaveBeenCalledWith("");
+  });
+
+  it("does not allow Next to persist an empty host", async () => {
+    const store = useWidgetStore.getState();
+    store.setConfigDir("/Users/me/.darwin");
+    store.setHosts(["mbp"]);
+
+    render(<SetupStep />);
+
+    expect(await screen.findByRole("button", { name: "Next" })).toBeDisabled();
+  });
+});
diff --git a/apps/native/src/components/widget/steps/setup-step.tsx b/apps/native/src/components/widget/steps/setup-step.tsx
index a3ddf4f9..21ac369e 100644
--- a/apps/native/src/components/widget/steps/setup-step.tsx
+++ b/apps/native/src/components/widget/steps/setup-step.tsx
@@ -21,6 +21,7 @@ export function SetupStep() {
   const host = useWidgetStore((state) => state.host);
   const [configDirConfirmed, setConfigDirConfirmed] = useState(false);
   const [selectedHost, setSelectedHost] = useState<string>("");
+  const effectiveHost = selectedHost || host;
 
   const { saveHost } = useDarwinConfig();
 
@@ -82,7 +83,7 @@ export function SetupStep() {
           ) : (
             <BootstrapConfig label="2. Configuration" />
           )}
-          <Button onClick={() => saveHost(selectedHost)}>
+          <Button disabled={!effectiveHost} onClick={() => saveHost(effectiveHost)}>
             Next
           </Button>
         </div>