diff --git a/src/main.rs b/src/main.rs
index 1396e74..f4df036 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -83,11 +83,11 @@ fn main() -> Result<(), Error> {
     let color = create_color(args.color[0]);
     let char = Box::new(SimpleCharSampler::new(args.chars));
 
-    let sampler = Box::new(ComposedSampler::new(animation, fill, color, char));
-    let surface = Box::new(WriteSurface::new(stdout(), width, height));
+    let sampler = ComposedSampler::new(animation, fill, color, char);
+    let surface =WriteSurface::new(stdout(), width, height);
 
-    let renderer = Box::new(SamplerRenderer::new(surface, sampler));
-    let timer = Box::new(SimpleTimer::new(Duration::from_millis(1000 / 60)));
+    let renderer = SamplerRenderer::new(surface, sampler);
+    let timer = SimpleTimer::new(Duration::from_millis(1000 / 60));
     let runner = Runner::new(Duration::from_secs(2), timer, renderer);
 
     runner.run()
diff --git a/src/render.rs b/src/render.rs
index 45329c9..6e7ae9b 100644
--- a/src/render.rs
+++ b/src/render.rs
@@ -9,19 +9,18 @@ pub trait Renderer {
     fn finish(&mut self) -> Result<(), Error>;
 }
 
-pub struct SamplerRenderer {
-    surface: Box<dyn Surface>,
-    sampler: Box<dyn Sampler>,
+pub struct SamplerRenderer<TSurface, TSampler> {
+    surface: TSurface,
+    sampler: TSampler,
 }
 
-impl SamplerRenderer {
-    pub fn new(surface: Box<dyn Surface>,
-               sampler: Box<dyn Sampler>) -> Self {
+impl<T1, T2> SamplerRenderer<T1, T2> {
+    pub fn new(surface: T1, sampler: T2) -> Self {
         Self { surface, sampler }
     }
 }
 
-impl Renderer for SamplerRenderer {
+impl<T1: Surface, T2: Sampler> Renderer for SamplerRenderer<T1, T2> {
     fn render(&mut self, step: f32) {
         for x in 0..self.surface.width() {
             for y in 0..self.surface.height() {
@@ -56,8 +55,8 @@ mod test {
 
     #[test]
     fn render() {
-        let mut surface = Box::new(MockSurface::new());
-        let mut sampler = Box::new(MockSampler::new());
+        let mut surface = MockSurface::new();
+        let mut sampler = MockSampler::new();
 
         sampler.expect_sample().withf(|_, pos| pos.x == 0.0 && pos.y == 0.0).returning(|_,_| Sample::Clear);
         sampler.expect_sample().withf(|_, pos| pos.x == 1.0 && pos.y == 0.0).returning(|_,_| Sample::Keep);
@@ -80,8 +79,8 @@ mod test {
 
     #[test]
     fn present() {
-        let mut surface = Box::new(MockSurface::new());
-        let sampler = Box::new(MockSampler::new());
+        let mut surface = MockSurface::new();
+        let sampler = MockSampler::new();
 
         surface.expect_present().once().returning(|| Ok(()));
 
@@ -92,8 +91,8 @@ mod test {
 
     #[test]
     fn finish() {
-        let mut surface = Box::new(MockSurface::new());
-        let sampler = Box::new(MockSampler::new());
+        let mut surface = MockSurface::new();
+        let sampler = MockSampler::new();
 
         surface.expect_finish().once().returning(|| Ok(()));
 
diff --git a/src/runner.rs b/src/runner.rs
index 142b010..6ff01be 100644
--- a/src/runner.rs
+++ b/src/runner.rs
@@ -3,16 +3,16 @@ use anyhow::Error;
 use crate::Renderer;
 use crate::timer::Timer;
 
-pub struct Runner {
-    timer: Box<dyn Timer>,
+pub struct Runner<TTimer, TRenderer> {
+    timer: TTimer,
     ticks: u128,
-    renderer: Box<dyn Renderer>,
+    renderer: TRenderer,
 }
 
-impl Runner {
+impl<T1: Timer, T2: Renderer> Runner<T1, T2> {
     pub fn new(duration: Duration,
-               timer: Box<dyn Timer>,
-               renderer: Box<dyn Renderer>) -> Self {
+               timer: T1,
+               renderer: T2) -> Self {
         let ticks = duration.as_nanos() / timer.delay().as_nanos();
 
         Self { timer, ticks, renderer }