diff --git a/base-sysroot.tar.gz b/base-sysroot.tar.gz
index 4ed71e86..826e7a70 100644
Binary files a/base-sysroot.tar.gz and b/base-sysroot.tar.gz differ
diff --git a/userspace/programs/WindowServer/WindowServer.cpp b/userspace/programs/WindowServer/WindowServer.cpp
index c7760e64..5be523aa 100644
--- a/userspace/programs/WindowServer/WindowServer.cpp
+++ b/userspace/programs/WindowServer/WindowServer.cpp
@@ -13,8 +13,9 @@
 
 #include <unistd.h>
 
-WindowServer::WindowServer(Framebuffer& framebuffer)
+WindowServer::WindowServer(Framebuffer& framebuffer, int32_t corner_radius)
 	: m_framebuffer(framebuffer)
+	, m_corner_radius(corner_radius)
 	, m_cursor({ framebuffer.width / 2, framebuffer.height / 2 })
 	, m_font(MUST(LibFont::Font::load("/usr/share/fonts/lat0-16.psfu"_sv)))
 {
@@ -338,45 +339,43 @@ void WindowServer::invalidate(Rectangle area)
 	{
 		auto& window = *pwindow;
 
-		const int32_t corner_radius = 5;
-
 		const Rectangle fast_areas[] {
 			{
-				window.full_x() + corner_radius,
+				window.full_x() + m_corner_radius,
 				window.full_y(),
-				window.full_width() - 2 * corner_radius,
-				corner_radius
+				window.full_width() - 2 * m_corner_radius,
+				m_corner_radius
 			},
 			{
 				window.full_x(),
-				window.full_y() + corner_radius,
+				window.full_y() + m_corner_radius,
 				window.full_width(),
-				window.full_height() - 2 * corner_radius
+				window.full_height() - 2 * m_corner_radius
 			},
 			{
-				window.full_x() + corner_radius,
-				window.full_y() + window.full_height() - corner_radius,
-				window.full_width() - 2 * corner_radius,
-				corner_radius
+				window.full_x() + m_corner_radius,
+				window.full_y() + window.full_height() - m_corner_radius,
+				window.full_width() - 2 * m_corner_radius,
+				m_corner_radius
 			}
 		};
 
 		const Position corner_centers[] {
 			{
-				window.full_x()                              + corner_radius,
-				window.full_y()                              + corner_radius,
+				window.full_x()                              + m_corner_radius,
+				window.full_y()                              + m_corner_radius,
 			},
 			{
-				window.full_x() + (window.full_width() - 1)  - corner_radius,
-				window.full_y()                              + corner_radius,
+				window.full_x() + (window.full_width() - 1)  - m_corner_radius,
+				window.full_y()                              + m_corner_radius,
 			},
 			{
-				window.full_x()                              + corner_radius,
-				window.full_y() + (window.full_height() - 1) - corner_radius,
+				window.full_x()                              + m_corner_radius,
+				window.full_y() + (window.full_height() - 1) - m_corner_radius,
 			},
 			{
-				window.full_x() + (window.full_width()  - 1) - corner_radius,
-				window.full_y() + (window.full_height() - 1) - corner_radius,
+				window.full_x() + (window.full_width()  - 1) - m_corner_radius,
+				window.full_y() + (window.full_height() - 1) - m_corner_radius,
 			},
 		};
 
@@ -384,26 +383,26 @@ void WindowServer::invalidate(Rectangle area)
 			{
 				window.full_x(),
 				window.full_y(),
-				corner_radius,
-				corner_radius
+				m_corner_radius,
+				m_corner_radius
 			},
 			{
-				window.full_x() + window.full_width() - corner_radius,
+				window.full_x() + window.full_width() - m_corner_radius,
 				window.full_y(),
-				corner_radius,
-				corner_radius
+				m_corner_radius,
+				m_corner_radius
 			},
 			{
 				window.full_x(),
-				window.full_y() + window.full_height() - corner_radius,
-				corner_radius,
-				corner_radius
+				window.full_y() + window.full_height() - m_corner_radius,
+				m_corner_radius,
+				m_corner_radius
 			},
 			{
-				window.full_x() + window.full_width() - corner_radius,
-				window.full_y() + window.full_height() - corner_radius,
-				corner_radius,
-				corner_radius
+				window.full_x() + window.full_width() - m_corner_radius,
+				window.full_y() + window.full_height() - m_corner_radius,
+				m_corner_radius,
+				m_corner_radius
 			}
 		};
 
@@ -418,7 +417,7 @@ void WindowServer::invalidate(Rectangle area)
 					const int32_t dy = pos.y - corner_centers[i].y;
 					if (2 * (dy > 0) + (dx > 0) != i)
 						continue;
-					if (dx * dx + dy * dy >= corner_radius * corner_radius)
+					if (dx * dx + dy * dy >= m_corner_radius * m_corner_radius)
 						return true;
 				}
 				return false;
diff --git a/userspace/programs/WindowServer/WindowServer.h b/userspace/programs/WindowServer/WindowServer.h
index 7365882d..fb6e22db 100644
--- a/userspace/programs/WindowServer/WindowServer.h
+++ b/userspace/programs/WindowServer/WindowServer.h
@@ -19,7 +19,7 @@
 class WindowServer
 {
 public:
-	WindowServer(Framebuffer& framebuffer);
+	WindowServer(Framebuffer& framebuffer, int32_t corner_radius);
 
 	BAN::ErrorOr<void> set_background_image(BAN::UniqPtr<LibImage::Image>);
 
@@ -48,6 +48,8 @@ private:
 	BAN::Vector<BAN::RefPtr<Window>> m_client_windows;
 	BAN::Vector<int> m_client_fds;
 
+	const int32_t m_corner_radius;
+
 	BAN::Vector<uint8_t> m_pages_to_sync_bitmap;
 
 	BAN::UniqPtr<LibImage::Image> m_background_image;
diff --git a/userspace/programs/WindowServer/main.cpp b/userspace/programs/WindowServer/main.cpp
index 755b6fdc..2d341b07 100644
--- a/userspace/programs/WindowServer/main.cpp
+++ b/userspace/programs/WindowServer/main.cpp
@@ -19,6 +19,7 @@
 struct Config
 {
 	BAN::UniqPtr<LibImage::Image> background_image;
+	int32_t corner_radius = 0;
 };
 
 BAN::Optional<BAN::String> file_read_line(FILE* file)
@@ -88,6 +89,15 @@ Config parse_config()
 			else
 				config.background_image = image.release_value();
 		}
+		else if (variable == "corner-radius"_sv)
+		{
+			char* endptr = nullptr;
+			long corner_radius = strtol(value.data(), &endptr, 0);
+			if (corner_radius < 0 || corner_radius == LONG_MAX || corner_radius >= INT32_MAX)
+				dwarnln("invalid corner-radius: '{}'", value);
+			else
+				config.corner_radius = corner_radius;
+		}
 		else
 		{
 			dwarnln("Unknown config variable: {}", variable);
@@ -176,7 +186,7 @@ int main()
 
 	auto config = parse_config();
 
-	WindowServer window_server(framebuffer);
+	WindowServer window_server(framebuffer, config.corner_radius);
 	if (config.background_image)
 		if (auto ret = window_server.set_background_image(BAN::move(config.background_image)); ret.is_error())
 			dwarnln("Could not set background image: {}", ret.error());