diff --git a/Cargo.toml b/Cargo.toml
index c9dff52..482f978 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -4,4 +4,5 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
+rayon = "1"
 strum = { version = "0.24", features = ["derive"] }
diff --git a/src/lib.rs b/src/lib.rs
index 8619304..81ff81f 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,10 +1,11 @@
 //! Cyborg is a high-performance, modern, experimental rendering engine written
 //! in Rust.
 
+use rayon::prelude::*;
 use strum::IntoEnumIterator;
 
-pub mod phase;
 pub mod pass;
+pub mod phase;
 
 use pass::*;
 use phase::*;
@@ -17,32 +18,41 @@ impl Renderer {
     pub fn render(&mut self) {
         let frame_index = 0;
 
-        let mut phase_passes = PhaseMultiMap::<usize>::default();
+        let phase_passes = PhaseMultiMap::<usize>::default();
+        let phase_passes = std::sync::Mutex::new(phase_passes);
 
-        let mut phases_buf = PhaseList::default();
-        for (pass_index, rp) in self.render_passes.iter_mut().enumerate() {
-            phases_buf.clear();
-            rp.begin_frame(frame_index, &mut phases_buf);
-            phase_passes.insert_multi(&phases_buf, pass_index);
-        }
+        self.render_passes
+            .par_iter_mut()
+            .enumerate()
+            .for_each(|(pass_index, rp)| {
+                let mut phases_buf = PhaseList::default();
+                phases_buf.clear();
+                rp.begin_frame(frame_index, &mut phases_buf);
+                phase_passes
+                    .lock()
+                    .unwrap()
+                    .insert_multi(&phases_buf, pass_index);
+            });
 
-        for phase in PrePhase::iter() {
+        let phase_passes = phase_passes.into_inner().unwrap();
+
+        PrePhase::iter().par_bridge().for_each(|phase| {
             for pass_index in phase_passes.iter_pre(&phase) {
                 let pass = &self.render_passes[*pass_index];
                 let mut encoder = gpu::RenderBundleEncoder;
                 pass.render_pre(phase, frame_index, &mut encoder);
             }
-        }
+        });
 
         let viewport = ViewportData;
 
-        for phase in ViewportPhase::iter() {
+        ViewportPhase::iter().par_bridge().for_each(|phase| {
             for pass_index in phase_passes.iter_viewport(&phase) {
                 let pass = &self.render_passes[*pass_index];
                 let mut encoder = gpu::RenderBundleEncoder;
                 pass.render_viewport(phase, frame_index, &viewport, &mut encoder);
             }
-        }
+        });
     }
 }
 
@@ -55,3 +65,52 @@ pub mod gpu {
     /// - secondary command buffer in Vulkan
     pub struct RenderBundleEncoder;
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    struct DummyPass;
+
+    impl RenderPass for DummyPass {
+        type FrameData = usize;
+
+        fn create_frame_data(&mut self) -> usize {
+            0
+        }
+
+        fn begin_frame(&mut self, data: &mut Self::FrameData, phases: &mut PhaseList) {
+            println!("begin_frame()");
+        }
+
+        fn render_pre(
+            &self,
+            phase: PrePhase,
+            data: &Self::FrameData,
+            cmds: &mut gpu::RenderBundleEncoder,
+        ) {
+            println!("render_pre(phase: {:?})", phase);
+        }
+
+        fn render_viewport(
+            &self,
+            phase: ViewportPhase,
+            data: &Self::FrameData,
+            viewport: &ViewportData,
+            cmds: &mut gpu::RenderBundleEncoder,
+        ) {
+            println!("render_viewport(phase: {:?})", phase);
+        }
+    }
+
+    #[test]
+    fn dummy_pass() {
+        use std::sync::{Arc, RwLock};
+        let dummy_pass = DummyPass;
+        let dummy_pass = Arc::new(RwLock::new(dummy_pass));
+        let dummy_pass = RenderPassBox::new(dummy_pass, 1);
+        let render_passes = vec![dummy_pass];
+        let mut renderer = Renderer { render_passes };
+        renderer.render();
+    }
+}
diff --git a/src/pass.rs b/src/pass.rs
index c18a80e..0570489 100644
--- a/src/pass.rs
+++ b/src/pass.rs
@@ -15,9 +15,9 @@ pub struct ViewportData;
 ///
 /// Rendering functions record their GPU commands using the [gpu::RenderBundleEncoder]
 /// passed to them.
-pub trait RenderPass {
+pub trait RenderPass: Send + Sync {
     /// A structure that contains a pass's per-frame data.
-    type FrameData;
+    type FrameData: Send + Sync;
 
     /// Sets up a new instance of [Self::FrameData].
     ///
@@ -57,7 +57,7 @@ pub trait RenderPass {
 ///
 /// Functions on this trait map one-to-one with [RenderPass], except that
 /// frame data is passed by index and not by reference.
-pub trait RenderPassBoxTrait {
+pub trait RenderPassBoxTrait: Send + Sync {
     fn begin_frame(&mut self, data_index: usize, phases: &mut PhaseList);
 
     fn render_pre(&self, phase: PrePhase, data_index: usize, cmds: &mut gpu::RenderBundleEncoder);
@@ -77,21 +77,21 @@ pub struct RenderPassBox<T: RenderPass> {
     frame_data: Vec<T::FrameData>,
 }
 
-impl<T: RenderPass> RenderPassBox<T> {
+impl<T: 'static + RenderPass> RenderPassBox<T> {
     /// Creates a new boxed render pass.
     ///
     /// Calls to [RenderPassBoxTrait] functions with frame indices greater
     /// than or equal to `frame_num` are out-of-bounds and will panic.
-    pub fn new(render_pass: Arc<RwLock<T>>, frame_num: usize) -> Self {
+    pub fn new(render_pass: Arc<RwLock<T>>, frame_num: usize) -> Box<dyn RenderPassBoxTrait> {
         let frame_data = {
             let mut lock = render_pass.write().unwrap();
             (0..frame_num).map(|_| lock.create_frame_data()).collect()
         };
 
-        Self {
+        Box::new(Self {
             render_pass,
             frame_data,
-        }
+        })
     }
 }