diff --git a/crates/fj-host/src/evaluator.rs b/crates/fj-host/src/evaluator.rs
deleted file mode 100644
index 4be4ff05a5..0000000000
--- a/crates/fj-host/src/evaluator.rs
+++ /dev/null
@@ -1,99 +0,0 @@
-//use std::thread;
-
-//use crossbeam_channel::{Receiver, SendError, Sender};
-use fj_interop::processed_shape::ProcessedShape;
-
-use crate::Error; // Model};
-
-// -----------------
-// This file becomes unnecessary because all the processing happens directly
-// in `host.rs`.
-// -----------------
-
-/*
-/// Evaluates a model in a background thread
-pub struct Evaluator {
-    trigger_tx: Sender<TriggerEvaluation>,
-    event_rx: Receiver<ModelEvent>,
-}
-
-impl Evaluator {
-    /// Create an `Evaluator` from a model
-    //pub fn new(event_tx: EventLoopProxy<ModelEvent>, model: Model) -> Self {
-    pub fn from_model(model: Model) -> Self {
-        let (event_tx, event_rx) = crossbeam_channel::bounded(0);
-        let (trigger_tx, trigger_rx) = crossbeam_channel::bounded(0);
-
-        thread::spawn(move || {
-            while matches!(trigger_rx.recv(), Ok(TriggerEvaluation)) {
-                if let Err(SendError(_)) =
-                    event_tx.send(ModelEvent::ChangeDetected)
-                {
-                    break;
-                }
-
-                let _evaluation = match model.evaluate() {
-                    Ok(evaluation) => evaluation,
-                    Err(err) => {
-                        if let Err(SendError(_)) =
-                            event_tx.send(ModelEvent::Error(err))
-                        {
-                            break;
-                        }
-                        continue;
-                    }
-                };
-
-                /*
-                if let Err(SendError(_)) =
-                    event_tx.send(ModelEvent::Evaluation(evaluation))
-                {
-                    break;
-                };
-                */
-            }
-
-            // The channel is disconnected, which means this instance of
-            // `Evaluator`, as well as all `Sender`s created from it, have been
-            // dropped. We're done.
-        });
-
-        Self {
-            trigger_tx,
-            event_rx,
-        }
-    }
-
-    /// Access a channel for triggering evaluations
-    pub fn trigger(&self) -> Sender<TriggerEvaluation> {
-        self.trigger_tx.clone()
-    }
-
-    /// Access a channel for receiving status updates
-    pub fn events(&self) -> Receiver<ModelEvent> {
-        self.event_rx.clone()
-    }
-}
-
-/// Command received by [`Evaluator`] through its channel
-pub struct TriggerEvaluation;
-*/
-
-/// An event emitted by the host thread
-#[derive(Debug)]
-pub enum ModelEvent {
-    /// A new model is being watched
-    StartWatching,
-
-    /// A change in the model has been detected
-    ChangeDetected,
-
-    /// The model has been evaluated
-    Evaluated,
-
-    /// The model has been processed
-    ProcessedShape(ProcessedShape),
-
-    /// An error
-    Error(Error),
-}
diff --git a/crates/fj-host/src/host.rs b/crates/fj-host/src/host.rs
index b0a14ad7a0..c8a7bc0387 100644
--- a/crates/fj-host/src/host.rs
+++ b/crates/fj-host/src/host.rs
@@ -1,10 +1,11 @@
 use std::thread;
 
 use crossbeam_channel::{unbounded, Receiver, Sender};
+use fj_interop::processed_shape::ProcessedShape;
 use fj_operations::shape_processor::ShapeProcessor;
 use winit::event_loop::EventLoopProxy;
 
-use crate::{HostCommand, HostHandle, Model, ModelEvent, Watcher};
+use crate::{Error, HostCommand, HostHandle, Model, Watcher};
 
 // Use a zero-sized error type to silence `#[warn(clippy::result_large_err)]`.
 // The only error from `EventLoopProxy::send_event` is `EventLoopClosed<T>`,
@@ -117,3 +118,22 @@ impl Host {
         Ok(())
     }
 }
+
+/// An event emitted by the host thread
+#[derive(Debug)]
+pub enum ModelEvent {
+    /// A new model is being watched
+    StartWatching,
+
+    /// A change in the model has been detected
+    ChangeDetected,
+
+    /// The model has been evaluated
+    Evaluated,
+
+    /// The model has been processed
+    ProcessedShape(ProcessedShape),
+
+    /// An error
+    Error(Error),
+}
diff --git a/crates/fj-host/src/lib.rs b/crates/fj-host/src/lib.rs
index 0fb56e7acd..0420c25b5f 100644
--- a/crates/fj-host/src/lib.rs
+++ b/crates/fj-host/src/lib.rs
@@ -15,7 +15,6 @@
 
 #![warn(missing_docs)]
 
-mod evaluator;
 mod host;
 mod host_handle;
 mod model;
@@ -24,8 +23,7 @@ mod platform;
 mod watcher;
 
 pub use self::{
-    evaluator::ModelEvent,
-    host::{EventLoopClosed, Host},
+    host::{EventLoopClosed, Host, ModelEvent},
     host_handle::{HostCommand, HostHandle},
     model::{Error, Evaluation, Model},
     parameters::Parameters,