diff --git a/ui/build.rs b/ui/build.rs
index 20d81b9..c30dee2 100644
--- a/ui/build.rs
+++ b/ui/build.rs
@@ -1,20 +1,23 @@
 // Generates static assets.
 
 use std::env;
+use std::error::Error;
 use std::fs::File;
 use std::io::Write;
 use std::path::Path;
 
 use sass_rs::{self, Options};
 
-fn main() {
+fn main() -> Result<(), Box<dyn Error>> {
     let dir = env::var("CARGO_MANIFEST_DIR").unwrap();
     let scss_dir = Path::new(&dir).join("scss");
     let source_css_file = scss_dir.join("stoptime.scss");
     let css_dir = Path::new(&dir).join("static").join("css");
     let target_css_file = css_dir.join("stoptime.css");
 
-    let sass = sass_rs::compile_file(&source_css_file, Options::default()).unwrap();
+    let sass = sass_rs::compile_file(&source_css_file, Options::default())
+        .map_err(|err| format!("Sass compilation failed: {}", err))?;
     let mut f = File::create(&target_css_file).unwrap();
     f.write_all(sass.as_bytes()).unwrap();
+    Ok(())
 }