diff --git a/crates/squozen/Cargo.toml b/crates/squozen/Cargo.toml
index 37c6f5b..75febcb 100644
--- a/crates/squozen/Cargo.toml
+++ b/crates/squozen/Cargo.toml
@@ -15,3 +15,7 @@ fnmatch-sys = "1.0.0"
 [[bin]]
 name = "bench_patprep"
 path = "bench/bench_patprep.rs"
+
+[profile.release]
+opt-level = 3
+
diff --git a/crates/squozen/bench/bench_patprep.rs b/crates/squozen/bench/bench_patprep.rs
index 4e09fd0..d3a11b8 100644
--- a/crates/squozen/bench/bench_patprep.rs
+++ b/crates/squozen/bench/bench_patprep.rs
@@ -1,13 +1,11 @@
-use squozen::prepare_pattern::prepare_pattern_raw;
+use squozen::prepare_pattern::prepare_pattern;
 
 const COUNT: usize = 5 * 1000 * 1000 * 100;
 
 fn main() {
     let mut end = COUNT;
-    let mut dest = Vec::<u8>::with_capacity(100);
     while end > 0 {
-        dest.clear();
-        prepare_pattern_raw(b"/foo/bar/whatever[0-9]*", &mut dest);
+        let _ = prepare_pattern(b"/foo/bar/whatever[0-9]*");
         end = end - 1;
     }
 }
diff --git a/crates/squozen/src/prepare_pattern.rs b/crates/squozen/src/prepare_pattern.rs
index e8a0188..1237f17 100644
--- a/crates/squozen/src/prepare_pattern.rs
+++ b/crates/squozen/src/prepare_pattern.rs
@@ -26,17 +26,13 @@ where
     }
     return alt;
 }
+#[derive(Debug, PartialEq)]
+pub struct PatternError;
 
-pub fn prepare_pattern(name: &[u8]) -> Vec<u8> {
-    let mut dest = Vec::with_capacity(116);
-    prepare_pattern_raw(name, &mut dest);
-    dest
-}
-
-pub fn prepare_pattern_raw(name: &[u8], dest: &mut Vec<u8>) {
+pub fn prepare_pattern(name: &[u8]) -> Result<Vec<u8>, PatternError> {
     let eol = name.len();
     if eol == 0 {
-        panic!("Library error - This function should never be called with an empty string.")
+        return Err(PatternError);
     }
 
     // After this point, eol always points to the index from where we want to
@@ -48,13 +44,15 @@ pub fn prepare_pattern_raw(name: &[u8], dest: &mut Vec<u8>) {
         eol = if eol > 0 { eol - 1 } else { 0 }
     }
 
+    let mut dest = Vec::with_capacity(116);
+
     if eol == 0 {
         if GLOBCHARS.contains(&name[0]) {
             dest.push(b'/');
-            return;
+            return Ok(dest);
         } else {
             dest.push(name[0]);
-            return;
+            return Ok(dest);
         };
     }
 
@@ -69,6 +67,8 @@ pub fn prepare_pattern_raw(name: &[u8], dest: &mut Vec<u8>) {
     } else {
         dest.extend_from_slice(&name[start..eol + 1]);
     }
+
+    Ok(dest)
 }
 
 #[cfg(test)]
@@ -77,24 +77,28 @@ mod tests {
 
     #[test]
     fn test_patterns() {
-        assert_eq!(prepare_pattern(b"testing"), b"testing");
-        assert_eq!(prepare_pattern(b"t"), b"t");
-        assert_eq!(prepare_pattern(b"test*"), b"test");
-        assert_eq!(prepare_pattern(b"test*"), b"test");
+        assert_eq!(prepare_pattern(b""), Err(PatternError));
+        assert_eq!(prepare_pattern(b"testing").unwrap(), b"testing");
+        assert_eq!(prepare_pattern(b"t").unwrap(), b"t");
+        assert_eq!(prepare_pattern(b"test*").unwrap(), b"test");
+        assert_eq!(prepare_pattern(b"test*").unwrap(), b"test");
         assert_eq!(
-            prepare_pattern(b"/foo/bar/whatever[0-9]"),
+            prepare_pattern(b"/foo/bar/whatever[0-9]").unwrap(),
             b"/foo/bar/whatever"
         );
-        assert_eq!(prepare_pattern(b"/foo/bar/whatever*[0-9]"), b"/");
+        assert_eq!(prepare_pattern(b"/foo/bar/whatever*[0-9]").unwrap(), b"/");
         assert_eq!(
-            prepare_pattern(b"/foo/bar/whatever[0-9]"),
+            prepare_pattern(b"/foo/bar/whatever[0-9]").unwrap(),
             b"/foo/bar/whatever"
         );
         assert_eq!(
-            prepare_pattern(b"/foo/bar/whatever[0-9]*"),
+            prepare_pattern(b"/foo/bar/whatever[0-9]*").unwrap(),
             b"/foo/bar/whatever"
         );
-        assert_eq!(prepare_pattern(b"/foo/bar/*whatever[0-9]"), b"whatever");
-        assert_eq!(prepare_pattern(b"fooz]"), b"f");
+        assert_eq!(
+            prepare_pattern(b"/foo/bar/*whatever[0-9]").unwrap(),
+            b"whatever"
+        );
+        assert_eq!(prepare_pattern(b"fooz]").unwrap(), b"f");
     }
 }