diff --git a/src/content_type.rs b/src/content_type.rs
index 457ef00..3d9a25d 100644
--- a/src/content_type.rs
+++ b/src/content_type.rs
@@ -1,7 +1,22 @@
-// Requires: tokei = "12" in Cargo.toml
+use once_cell::sync::Lazy;
 use std::path::Path;
 use tokei::LanguageType;
 
+
+// Precompute all (shebang_prefix_bytes, language) pairs once.
+// Sort longest-first so more specific shebangs win.
+static SHEBANG_PREFIXES: Lazy<Vec<(&'static [u8], LanguageType)>> = Lazy::new(|| {
+    let mut v = Vec::new();
+    for &lang in LanguageType::list() {
+        for &sb in lang.shebangs() {
+            v.push((sb.as_bytes(), lang));
+        }
+    }
+    // Longest prefix first to prefer e.g. "#!/usr/bin/env python3" over "#!/usr/bin/env python"
+    v.sort_by(|a, b| b.0.len().cmp(&a.0.len()));
+    v
+});
+
 /// The type of content detected.
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum ContentType {
@@ -127,16 +142,12 @@ impl ContentInspector {
             }
         }
 
-        // 3) Shebang detection (in-memory): compare the first line to known shebangs.
+        // 3) Shebang detection (in-memory): match by longest prefix, byte-wise (no UTF-8 needed).
         if let Some(first_line) = content.split(|&b| b == b'\n').next() {
             if first_line.starts_with(b"#!") {
-                if let Ok(line) = std::str::from_utf8(first_line) {
-                    for &lang in LanguageType::list() {
-                        for &sb in lang.shebangs() {
-                            if line.starts_with(sb) {
-                                return Some(lang.name().to_string());
-                            }
-                        }
+                for (prefix, lang) in SHEBANG_PREFIXES.iter() {
+                    if first_line.starts_with(prefix) {
+                        return Some(lang.name().to_string());
                     }
                 }
             }
diff --git a/src/scanner/enumerate.rs b/src/scanner/enumerate.rs
index f4bac9d..a999f31 100644
--- a/src/scanner/enumerate.rs
+++ b/src/scanner/enumerate.rs
@@ -455,8 +455,8 @@ impl<'a> rayon::iter::ParallelIterator for GitRepoResultIter<'a> {
                     let origin = OriginSet::try_from_iter(md.first_seen.iter().map(|e| {
                         Origin::from_git_repo_with_first_commit(
                             Arc::clone(&repo_path),
-                            Arc::clone(&e.commit_metadata), // ← clone Arc
-                            String::from_utf8_lossy(&e.path).into_owned(),
+                            Arc::clone(&e.commit_metadata),
+                            String::from_utf8_lossy(&e.path).to_string(),
                         )
                     }))
                     .unwrap_or_else(|| Origin::from_git_repo(Arc::clone(&repo_path)).into());