diff --git a/src/render.rs b/src/render.rs
index f5285ba..727ddf9 100644
--- a/src/render.rs
+++ b/src/render.rs
@@ -23,19 +23,19 @@ pub trait Sample {
     fn sample(&mut self, rect: &Rectangle<Virtual>) -> impl PixelView<Pixel = Self::Pixel>;
 }
 
-pub trait Shader: Send + Sync {
+pub trait Shader: Send {
     fn draw(&self, surface_coords: &VirtualCoordinates, frame: usize) -> Rgb<u8>;
 }
 
-pub trait Surfaces: Send + Sync {
+pub trait Surfaces: Send {
     type Surface: Surface;
     type Error: Debug;
     fn new_surface(&mut self, area: Rectangle<Virtual>) -> Result<Self::Surface, Self::Error>;
     fn render_to<S: Sample>(&self, output: &mut S, frame: usize);
 }
 
-pub trait Surface: Send + Sync {
-    fn set_shader(&mut self, shader: Box<dyn Shader>);
+pub trait Surface: Send {
+    fn set_shader<T: Shader + 'static>(&mut self, shader: T);
     fn clear_shader(&mut self);
 
     fn set_rect(&mut self, rect: Rectangle<Virtual>);