diff --git a/apps/web/src/components/dashboard/QuickCaptureWidget.tsx b/apps/web/src/components/dashboard/QuickCaptureWidget.tsx
index 3a763e8..96cac82 100644
--- a/apps/web/src/components/dashboard/QuickCaptureWidget.tsx
+++ b/apps/web/src/components/dashboard/QuickCaptureWidget.tsx
@@ -3,8 +3,19 @@
 import { useState } from "react";
 import { Button } from "@mosaic/ui";
 import { useRouter } from "next/navigation";
+import { ComingSoon } from "@/components/ui/ComingSoon";
 
-export function QuickCaptureWidget(): React.JSX.Element {
+/**
+ * Check if we're in development mode (runtime check for testability)
+ */
+function isDevelopment(): boolean {
+  return process.env.NODE_ENV === "development";
+}
+
+/**
+ * Internal Quick Capture Widget implementation
+ */
+function QuickCaptureWidgetInternal(): React.JSX.Element {
   const [idea, setIdea] = useState("");
   const router = useRouter();
 
@@ -48,3 +59,27 @@ export function QuickCaptureWidget(): React.JSX.Element {
     </div>
   );
 }
+
+/**
+ * Quick Capture Widget (Dashboard version)
+ *
+ * In production: Shows Coming Soon placeholder
+ * In development: Full widget functionality
+ */
+export function QuickCaptureWidget(): React.JSX.Element {
+  // In production, show Coming Soon placeholder
+  if (!isDevelopment()) {
+    return (
+      <div className="bg-white rounded-lg shadow-sm border border-gray-200 p-6">
+        <ComingSoon
+          feature="Quick Capture"
+          description="Quickly jot down ideas for later organization. This feature is currently under development."
+          className="!p-0 !min-h-0"
+        />
+      </div>
+    );
+  }
+
+  // In development, show full widget functionality
+  return <QuickCaptureWidgetInternal />;
+}
diff --git a/apps/web/src/components/dashboard/__tests__/QuickCaptureWidget.test.tsx b/apps/web/src/components/dashboard/__tests__/QuickCaptureWidget.test.tsx
new file mode 100644
index 0000000..91cac92
--- /dev/null
+++ b/apps/web/src/components/dashboard/__tests__/QuickCaptureWidget.test.tsx
@@ -0,0 +1,93 @@
+/**
+ * QuickCaptureWidget (Dashboard) Component Tests
+ * Tests environment-based behavior
+ */
+
+import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
+import { render, screen } from "@testing-library/react";
+import { QuickCaptureWidget } from "../QuickCaptureWidget";
+
+// Mock next/navigation
+vi.mock("next/navigation", () => ({
+  useRouter: (): { push: () => void } => ({
+    push: vi.fn(),
+  }),
+}));
+
+describe("QuickCaptureWidget (Dashboard)", (): void => {
+  beforeEach((): void => {
+    vi.clearAllMocks();
+  });
+
+  afterEach((): void => {
+    vi.unstubAllEnvs();
+  });
+
+  describe("Development mode", (): void => {
+    beforeEach((): void => {
+      vi.stubEnv("NODE_ENV", "development");
+    });
+
+    it("should render the widget form in development", (): void => {
+      render(<QuickCaptureWidget />);
+
+      // Should show the header
+      expect(screen.getByText("Quick Capture")).toBeInTheDocument();
+      // Should show the textarea
+      expect(screen.getByRole("textbox")).toBeInTheDocument();
+      // Should show the Save Note button
+      expect(screen.getByRole("button", { name: /save note/i })).toBeInTheDocument();
+      // Should show the Create Task button
+      expect(screen.getByRole("button", { name: /create task/i })).toBeInTheDocument();
+      // Should NOT show Coming Soon badge
+      expect(screen.queryByText("Coming Soon")).not.toBeInTheDocument();
+    });
+
+    it("should have a placeholder for the textarea", (): void => {
+      render(<QuickCaptureWidget />);
+
+      const textarea = screen.getByRole("textbox");
+      expect(textarea).toHaveAttribute("placeholder", "What's on your mind?");
+    });
+  });
+
+  describe("Production mode", (): void => {
+    beforeEach((): void => {
+      vi.stubEnv("NODE_ENV", "production");
+    });
+
+    it("should show Coming Soon placeholder in production", (): void => {
+      render(<QuickCaptureWidget />);
+
+      // Should show Coming Soon badge
+      expect(screen.getByText("Coming Soon")).toBeInTheDocument();
+      // Should show feature name
+      expect(screen.getByText("Quick Capture")).toBeInTheDocument();
+      // Should NOT show the textarea
+      expect(screen.queryByRole("textbox")).not.toBeInTheDocument();
+      // Should NOT show the buttons
+      expect(screen.queryByRole("button", { name: /save note/i })).not.toBeInTheDocument();
+      expect(screen.queryByRole("button", { name: /create task/i })).not.toBeInTheDocument();
+    });
+
+    it("should show description in Coming Soon placeholder", (): void => {
+      render(<QuickCaptureWidget />);
+
+      expect(screen.getByText(/jot down ideas for later organization/i)).toBeInTheDocument();
+    });
+  });
+
+  describe("Test mode (non-development)", (): void => {
+    beforeEach((): void => {
+      vi.stubEnv("NODE_ENV", "test");
+    });
+
+    it("should show Coming Soon placeholder in test mode", (): void => {
+      render(<QuickCaptureWidget />);
+
+      // Test mode is not development, so should show Coming Soon
+      expect(screen.getByText("Coming Soon")).toBeInTheDocument();
+      expect(screen.queryByRole("textbox")).not.toBeInTheDocument();
+    });
+  });
+});
diff --git a/apps/web/src/components/widgets/QuickCaptureWidget.tsx b/apps/web/src/components/widgets/QuickCaptureWidget.tsx
index b201f6f..46085a2 100644
--- a/apps/web/src/components/widgets/QuickCaptureWidget.tsx
+++ b/apps/web/src/components/widgets/QuickCaptureWidget.tsx
@@ -1,12 +1,48 @@
 /**
  * Quick Capture Widget - idea/brain dump input
+ *
+ * In production, shows a Coming Soon placeholder since the feature
+ * is not yet complete. Full functionality available in development mode.
  */
 
 import { useState } from "react";
 import { Send, Lightbulb } from "lucide-react";
 import type { WidgetProps } from "@mosaic/shared";
 
-export function QuickCaptureWidget({ id: _id, config: _config }: WidgetProps): React.JSX.Element {
+/**
+ * Check if we're in development mode (runtime check for testability)
+ */
+function isDevelopment(): boolean {
+  return process.env.NODE_ENV === "development";
+}
+
+/**
+ * Compact Coming Soon placeholder for widget contexts
+ */
+function WidgetComingSoon(): React.JSX.Element {
+  return (
+    <div className="flex flex-col h-full items-center justify-center p-4 text-center">
+      {/* Lightbulb Icon */}
+      <Lightbulb className="w-8 h-8 text-gray-300 mb-3" aria-hidden="true" />
+
+      {/* Coming Soon Badge */}
+      <span className="inline-block px-3 py-1 bg-blue-100 text-blue-700 text-xs font-medium rounded-full mb-2">
+        Coming Soon
+      </span>
+
+      {/* Feature Name */}
+      <h3 className="text-sm font-medium text-gray-700 mb-1">Quick Capture</h3>
+
+      {/* Description */}
+      <p className="text-xs text-gray-500">Quickly jot down ideas for later organization.</p>
+    </div>
+  );
+}
+
+/**
+ * Internal Quick Capture Widget implementation
+ */
+function QuickCaptureWidgetInternal({ id: _id, config: _config }: WidgetProps): React.JSX.Element {
   const [input, setInput] = useState("");
   const [isSubmitting, setIsSubmitting] = useState(false);
   const [recentCaptures, setRecentCaptures] = useState<string[]>([]);
@@ -92,3 +128,19 @@ export function QuickCaptureWidget({ id: _id, config: _config }: WidgetProps): R
     </div>
   );
 }
+
+/**
+ * Quick Capture Widget
+ *
+ * In production: Shows Coming Soon placeholder
+ * In development: Full widget functionality
+ */
+export function QuickCaptureWidget(props: WidgetProps): React.JSX.Element {
+  // In production, show Coming Soon placeholder
+  if (!isDevelopment()) {
+    return <WidgetComingSoon />;
+  }
+
+  // In development, show full widget functionality
+  return <QuickCaptureWidgetInternal {...props} />;
+}
diff --git a/apps/web/src/components/widgets/__tests__/QuickCaptureWidget.test.tsx b/apps/web/src/components/widgets/__tests__/QuickCaptureWidget.test.tsx
index 1fd2704..3c4d5e1 100644
--- a/apps/web/src/components/widgets/__tests__/QuickCaptureWidget.test.tsx
+++ b/apps/web/src/components/widgets/__tests__/QuickCaptureWidget.test.tsx
@@ -3,7 +3,7 @@
  * Following TDD principles
  */
 
-import { describe, it, expect, vi, beforeEach } from "vitest";
+import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
 import { render, screen, waitFor } from "@testing-library/react";
 import userEvent from "@testing-library/user-event";
 import { QuickCaptureWidget } from "../QuickCaptureWidget";
@@ -13,6 +13,12 @@ global.fetch = vi.fn() as typeof global.fetch;
 describe("QuickCaptureWidget", (): void => {
   beforeEach((): void => {
     vi.clearAllMocks();
+    // Set development mode by default for existing tests
+    vi.stubEnv("NODE_ENV", "development");
+  });
+
+  afterEach((): void => {
+    vi.unstubAllEnvs();
   });
 
   it("should render input field", (): void => {
@@ -147,4 +153,48 @@ describe("QuickCaptureWidget", (): void => {
       expect(screen.getByText("Test note")).toBeInTheDocument();
     });
   });
+
+  describe("Environment-based behavior", (): void => {
+    it("should show Coming Soon placeholder in production", (): void => {
+      vi.stubEnv("NODE_ENV", "production");
+
+      render(<QuickCaptureWidget id="quick-capture-1" />);
+
+      // Should show Coming Soon badge
+      expect(screen.getByText("Coming Soon")).toBeInTheDocument();
+      // Should show feature name
+      expect(screen.getByText("Quick Capture")).toBeInTheDocument();
+      // Should show description
+      expect(
+        screen.getByText(/Quickly jot down ideas for later organization/i)
+      ).toBeInTheDocument();
+      // Should NOT show the input field
+      expect(screen.queryByRole("textbox")).not.toBeInTheDocument();
+      // Should NOT show the submit button
+      expect(screen.queryByRole("button")).not.toBeInTheDocument();
+    });
+
+    it("should show full widget in development mode", (): void => {
+      vi.stubEnv("NODE_ENV", "development");
+
+      render(<QuickCaptureWidget id="quick-capture-1" />);
+
+      // Should show the input field
+      expect(screen.getByRole("textbox")).toBeInTheDocument();
+      // Should show the submit button
+      expect(screen.getByRole("button", { name: /submit/i })).toBeInTheDocument();
+      // Should NOT show Coming Soon badge
+      expect(screen.queryByText("Coming Soon")).not.toBeInTheDocument();
+    });
+
+    it("should show Coming Soon placeholder in test mode (non-development)", (): void => {
+      vi.stubEnv("NODE_ENV", "test");
+
+      render(<QuickCaptureWidget id="quick-capture-1" />);
+
+      // Test mode is not development, so should show Coming Soon
+      expect(screen.getByText("Coming Soon")).toBeInTheDocument();
+      expect(screen.queryByRole("textbox")).not.toBeInTheDocument();
+    });
+  });
 });