diff --git a/Cargo.lock b/Cargo.lock
index 0785bde..74ed358 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2286,6 +2286,8 @@ version = "0.1.0"
 dependencies = [
  "dpi",
  "ely_domain",
+ "serde",
+ "serde_json",
  "servo",
  "thiserror 2.0.18",
  "url",
diff --git a/Cargo.toml b/Cargo.toml
index f07de41..aadf8f8 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -24,6 +24,7 @@ servo = "0.1.0"
 sha2 = "0.10.9"
 semver = "1.0.28"
 serde = { version = "1.0.228", features = ["derive"] }
+serde_json = "1.0.145"
 thiserror = "2.0.12"
 toml = "1.1.2"
 url = "2.5.4"
diff --git a/crates/ely_servo_host/Cargo.toml b/crates/ely_servo_host/Cargo.toml
index 7d62463..49d6fb6 100644
--- a/crates/ely_servo_host/Cargo.toml
+++ b/crates/ely_servo_host/Cargo.toml
@@ -7,11 +7,18 @@ rust-version.workspace = true
 
 [features]
 default = []
-servo-engine = ["dep:dpi", "dep:servo", "dep:url"]
+servo-engine = ["dep:dpi", "dep:serde", "dep:serde_json", "dep:servo", "dep:url"]
+
+[[bin]]
+name = "ely_servo_sidecar"
+path = "src/bin/ely_servo_sidecar.rs"
+required-features = ["servo-engine"]
 
 [dependencies]
 dpi = { workspace = true, optional = true }
 ely_domain = { path = "../ely_domain" }
+serde = { workspace = true, optional = true }
+serde_json = { workspace = true, optional = true }
 servo = { workspace = true, optional = true }
 thiserror.workspace = true
 url = { workspace = true, optional = true }
diff --git a/crates/ely_servo_host/src/bin/ely_servo_sidecar.rs b/crates/ely_servo_host/src/bin/ely_servo_sidecar.rs
new file mode 100644
index 0000000..3c19dfa
--- /dev/null
+++ b/crates/ely_servo_host/src/bin/ely_servo_sidecar.rs
@@ -0,0 +1,247 @@
+use std::{env, num::ParseIntError, path::PathBuf, thread, time::Duration};
+
+use ely_domain::{ProfileId, TabId, UrlText};
+use ely_servo_host::{
+    NavigationRequest, RenderedFrame, ServoHost, ServoHostError, ServoSurfaceSize,
+    SoftwareServoHost, WebViewSnapshot, WebViewState,
+};
+use serde::Serialize;
+use thiserror::Error;
+
+const WAIT_ITERATIONS: usize = 5_000;
+const WAIT_INTERVAL: Duration = Duration::from_millis(2);
+
+fn main() -> Result<(), SidecarError> {
+    match parse_command(env::args())? {
+        SidecarCommand::Snapshot(args) => run_snapshot(args),
+    }
+}
+
+enum SidecarCommand {
+    Snapshot(SnapshotArgs),
+}
+
+struct SnapshotArgs {
+    url: UrlText,
+    rgba_out: PathBuf,
+    width: u32,
+    height: u32,
+}
+
+#[derive(Debug, Error)]
+enum SidecarError {
+    #[error("missing sidecar command")]
+    MissingCommand,
+
+    #[error("unknown sidecar command: {value}")]
+    UnknownCommand { value: String },
+
+    #[error("missing argument value for {name}")]
+    MissingArgumentValue { name: &'static str },
+
+    #[error("missing required argument: {name}")]
+    MissingRequiredArgument { name: &'static str },
+
+    #[error("unknown argument: {value}")]
+    UnknownArgument { value: String },
+
+    #[error("{name} must be a positive integer: {value}")]
+    InvalidInteger {
+        name: &'static str,
+        value: String,
+        #[source]
+        source: ParseIntError,
+    },
+
+    #[error("{name} must be greater than zero")]
+    ZeroDimension { name: &'static str },
+
+    #[error("rgba output path is empty")]
+    EmptyRgbaOutputPath,
+
+    #[error("timed out rendering {url}: {snapshot:?}")]
+    RenderTimeout { url: String, snapshot: Box<WebViewSnapshot> },
+
+    #[error(transparent)]
+    Domain(#[from] ely_domain::DomainError),
+
+    #[error(transparent)]
+    Host(#[from] ServoHostError),
+
+    #[error(transparent)]
+    Io(#[from] std::io::Error),
+
+    #[error(transparent)]
+    Json(#[from] serde_json::Error),
+}
+
+fn parse_command(args: impl IntoIterator<Item = String>) -> Result<SidecarCommand, SidecarError> {
+    let mut args = args.into_iter();
+    let _program_name = args.next();
+    let command = args.next().ok_or(SidecarError::MissingCommand)?;
+
+    match command.as_str() {
+        "snapshot" => parse_snapshot_args(args).map(SidecarCommand::Snapshot),
+        _ => Err(SidecarError::UnknownCommand { value: command }),
+    }
+}
+
+fn parse_snapshot_args(
+    args: impl IntoIterator<Item = String>,
+) -> Result<SnapshotArgs, SidecarError> {
+    let mut args = args.into_iter();
+    let mut url = None;
+    let mut rgba_out = None;
+    let mut width = None;
+    let mut height = None;
+
+    while let Some(name) = args.next() {
+        match name.as_str() {
+            "--url" => url = Some(UrlText::parse(next_argument(&mut args, "--url")?)?),
+            "--rgba-out" => {
+                rgba_out = Some(parse_output_path(next_argument(&mut args, "--rgba-out")?)?)
+            }
+            "--width" => {
+                width = Some(parse_dimension("--width", next_argument(&mut args, "--width")?)?)
+            }
+            "--height" => {
+                height = Some(parse_dimension("--height", next_argument(&mut args, "--height")?)?)
+            }
+            _ => return Err(SidecarError::UnknownArgument { value: name }),
+        }
+    }
+
+    Ok(SnapshotArgs {
+        url: url.ok_or(SidecarError::MissingRequiredArgument { name: "--url" })?,
+        rgba_out: rgba_out.ok_or(SidecarError::MissingRequiredArgument { name: "--rgba-out" })?,
+        width: width.ok_or(SidecarError::MissingRequiredArgument { name: "--width" })?,
+        height: height.ok_or(SidecarError::MissingRequiredArgument { name: "--height" })?,
+    })
+}
+
+fn next_argument(
+    args: &mut impl Iterator<Item = String>,
+    name: &'static str,
+) -> Result<String, SidecarError> {
+    args.next().ok_or(SidecarError::MissingArgumentValue { name })
+}
+
+fn parse_dimension(name: &'static str, value: String) -> Result<u32, SidecarError> {
+    let dimension = value.parse::<u32>().map_err(|source| SidecarError::InvalidInteger {
+        name,
+        value,
+        source,
+    })?;
+    if dimension == 0 {
+        return Err(SidecarError::ZeroDimension { name });
+    }
+
+    Ok(dimension)
+}
+
+fn parse_output_path(value: String) -> Result<PathBuf, SidecarError> {
+    if value.trim().is_empty() {
+        return Err(SidecarError::EmptyRgbaOutputPath);
+    }
+
+    Ok(PathBuf::from(value))
+}
+
+fn run_snapshot(args: SnapshotArgs) -> Result<(), SidecarError> {
+    let mut host = SoftwareServoHost::new(ServoSurfaceSize::new(args.width, args.height))?;
+    let tab_id = TabId::new();
+    let profile_id = ProfileId::new();
+    let webview_id = host.create_webview(tab_id.clone(), profile_id)?;
+
+    host.navigate(NavigationRequest {
+        webview_id: webview_id.clone(),
+        tab_id,
+        url: args.url.clone(),
+    })?;
+
+    let snapshot = wait_for_frame(&mut host, &webview_id, args.url.as_str())?;
+    let frame = host.last_rendered_frame()?;
+    std::fs::write(&args.rgba_out, frame.rgba_bytes())?;
+
+    serde_json::to_writer(
+        std::io::stdout().lock(),
+        &SnapshotReport::new(args.url.as_str(), &args.rgba_out, &snapshot, &frame),
+    )?;
+    Ok(())
+}
+
+fn wait_for_frame(
+    host: &mut SoftwareServoHost,
+    webview_id: &ely_domain::WebViewId,
+    url: &str,
+) -> Result<WebViewSnapshot, SidecarError> {
+    for _ in 0..WAIT_ITERATIONS {
+        host.tick();
+        let snapshot = host.snapshot(webview_id)?;
+        if snapshot.has_pending_frame() {
+            host.paint(webview_id)?;
+        }
+
+        let snapshot = host.snapshot(webview_id)?;
+        let has_rendered_frame =
+            host.last_rendered_frame().is_ok_and(|frame| frame.non_white_pixel_count() > 0);
+        if snapshot.state() == &WebViewState::Complete && has_rendered_frame {
+            return Ok(snapshot);
+        }
+
+        thread::sleep(WAIT_INTERVAL);
+    }
+
+    Err(SidecarError::RenderTimeout {
+        url: url.to_string(),
+        snapshot: Box::new(host.snapshot(webview_id)?),
+    })
+}
+
+#[derive(Serialize)]
+struct SnapshotReport {
+    requested_url: String,
+    loaded_url: Option<String>,
+    title: Option<String>,
+    rgba_path: String,
+    state: &'static str,
+    width: u32,
+    height: u32,
+    rgba_byte_count: usize,
+    opaque_pixel_count: u64,
+    non_white_pixel_count: u64,
+    sample_hash: u64,
+}
+
+impl SnapshotReport {
+    fn new(
+        requested_url: &str,
+        rgba_path: &std::path::Path,
+        snapshot: &WebViewSnapshot,
+        frame: &RenderedFrame,
+    ) -> Self {
+        Self {
+            requested_url: requested_url.to_string(),
+            loaded_url: snapshot.url().map(str::to_string),
+            title: snapshot.title().map(str::to_string),
+            rgba_path: rgba_path.display().to_string(),
+            state: state_label(snapshot.state()),
+            width: frame.width(),
+            height: frame.height(),
+            rgba_byte_count: frame.rgba_bytes().len(),
+            opaque_pixel_count: frame.opaque_pixel_count(),
+            non_white_pixel_count: frame.non_white_pixel_count(),
+            sample_hash: frame.sample_hash(),
+        }
+    }
+}
+
+fn state_label(state: &WebViewState) -> &'static str {
+    match state {
+        WebViewState::Created => "created",
+        WebViewState::Loading => "loading",
+        WebViewState::Complete => "complete",
+        WebViewState::Sleeping => "sleeping",
+        WebViewState::Crashed => "crashed",
+    }
+}
diff --git a/crates/ely_servo_host/tests/sidecar.rs b/crates/ely_servo_host/tests/sidecar.rs
new file mode 100644
index 0000000..c2dd350
--- /dev/null
+++ b/crates/ely_servo_host/tests/sidecar.rs
@@ -0,0 +1,56 @@
+#![cfg(feature = "servo-engine")]
+
+use std::{error::Error, process::Command};
+
+const WIDTH: u64 = 640;
+const HEIGHT: u64 = 480;
+
+#[test]
+fn sidecar_snapshots_prd_site_to_rgba_file() -> Result<(), Box<dyn Error>> {
+    let output_path =
+        std::env::temp_dir().join(format!("ely-servo-sidecar-{}-example.rgba", std::process::id()));
+    if output_path.exists() {
+        std::fs::remove_file(&output_path)?;
+    }
+
+    let output = Command::new(env!("CARGO_BIN_EXE_ely_servo_sidecar"))
+        .arg("snapshot")
+        .arg("--url")
+        .arg("https://example.com")
+        .arg("--rgba-out")
+        .arg(&output_path)
+        .arg("--width")
+        .arg(WIDTH.to_string())
+        .arg("--height")
+        .arg(HEIGHT.to_string())
+        .output()?;
+
+    assert!(
+        output.status.success(),
+        "status: {:?}\nstdout: {}\nstderr: {}",
+        output.status.code(),
+        String::from_utf8_lossy(&output.stdout),
+        String::from_utf8_lossy(&output.stderr)
+    );
+
+    let report: serde_json::Value = serde_json::from_slice(&output.stdout)?;
+    assert_eq!(report_field_as_u64(&report, "width")?, WIDTH);
+    assert_eq!(report_field_as_u64(&report, "height")?, HEIGHT);
+    assert_eq!(report_field_as_u64(&report, "rgba_byte_count")?, WIDTH * HEIGHT * 4);
+    assert!(report_field_as_u64(&report, "non_white_pixel_count")? > 0);
+    assert!(report_field_as_u64(&report, "sample_hash")? > 0);
+    assert_eq!(std::fs::metadata(&output_path)?.len(), WIDTH * HEIGHT * 4);
+
+    std::fs::remove_file(&output_path)?;
+    Ok(())
+}
+
+fn report_field_as_u64(
+    report: &serde_json::Value,
+    field: &'static str,
+) -> Result<u64, Box<dyn Error>> {
+    report
+        .get(field)
+        .and_then(serde_json::Value::as_u64)
+        .ok_or_else(|| format!("missing numeric report field: {field}").into())
+}
diff --git a/scripts/create_macos_app_bundle.sh b/scripts/create_macos_app_bundle.sh
index 0977a75..3235426 100755
--- a/scripts/create_macos_app_bundle.sh
+++ b/scripts/create_macos_app_bundle.sh
@@ -3,17 +3,21 @@ set -euo pipefail
 
 repo_root="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
 binary_path="${repo_root}/target/debug/ely_app"
+sidecar_path="${repo_root}/target/debug/ely_servo_sidecar"
 bundle_root="${repo_root}/target/macos/ELY Browser.app"
 contents_dir="${bundle_root}/Contents"
 macos_dir="${contents_dir}/MacOS"
 resources_dir="${contents_dir}/Resources"
 
 cargo build -p ely_app
+cargo build -p ely_servo_host --features servo-engine --bin ely_servo_sidecar
 
 rm -rf "${bundle_root}"
 mkdir -p "${macos_dir}" "${resources_dir}"
 cp "${repo_root}/packaging/macos/Info.plist" "${contents_dir}/Info.plist"
 cp "${binary_path}" "${macos_dir}/ely_app"
+cp "${sidecar_path}" "${macos_dir}/ely_servo_sidecar"
 chmod 755 "${macos_dir}/ely_app"
+chmod 755 "${macos_dir}/ely_servo_sidecar"
 
 echo "${bundle_root}"