diff --git a/crates/ruff/build.rs b/crates/ruff/build.rs
index 3615ee555d..bb5ac821bf 100644
--- a/crates/ruff/build.rs
+++ b/crates/ruff/build.rs
@@ -1,4 +1,8 @@
-use std::{fs, path::Path, process::Command};
+use std::{
+    fs,
+    path::{Path, PathBuf},
+    process::Command,
+};
 
 fn main() {
     // The workspace root directory is not available without walking up the tree
@@ -21,27 +25,22 @@ fn commit_info(workspace_root: &Path) {
         return;
     }
 
-    let git_head_path = git_dir.join("HEAD");
-    println!(
-        "cargo::rerun-if-changed={}",
-        git_head_path.as_path().display()
-    );
+    if let Some(git_head_path) = git_head(&git_dir) {
+        println!("cargo:rerun-if-changed={}", git_head_path.display());
 
-    let git_head_contents = fs::read_to_string(git_head_path);
-    if let Ok(git_head_contents) = git_head_contents {
-        // The contents are either a commit or a reference in the following formats
-        // - "<commit>" when the head is detached
-        // - "ref <ref>" when working on a branch
-        // If a commit, checking if the HEAD file has changed is sufficient
-        // If a ref, we need to add the head file for that ref to rebuild on commit
-        let mut git_ref_parts = git_head_contents.split_whitespace();
-        git_ref_parts.next();
-        if let Some(git_ref) = git_ref_parts.next() {
-            let git_ref_path = git_dir.join(git_ref);
-            println!(
-                "cargo::rerun-if-changed={}",
-                git_ref_path.as_path().display()
-            );
+        let git_head_contents = fs::read_to_string(git_head_path);
+        if let Ok(git_head_contents) = git_head_contents {
+            // The contents are either a commit or a reference in the following formats
+            // - "<commit>" when the head is detached
+            // - "ref <ref>" when working on a branch
+            // If a commit, checking if the HEAD file has changed is sufficient
+            // If a ref, we need to add the head file for that ref to rebuild on commit
+            let mut git_ref_parts = git_head_contents.split_whitespace();
+            git_ref_parts.next();
+            if let Some(git_ref) = git_ref_parts.next() {
+                let git_ref_path = git_dir.join(git_ref);
+                println!("cargo:rerun-if-changed={}", git_ref_path.display());
+            }
         }
     }
 
@@ -78,3 +77,30 @@ fn commit_info(workspace_root: &Path) {
         );
     }
 }
+
+fn git_head(git_dir: &Path) -> Option<PathBuf> {
+    // The typical case is a standard git repository.
+    let git_head_path = git_dir.join("HEAD");
+    if git_head_path.exists() {
+        return Some(git_head_path);
+    }
+    if !git_dir.is_file() {
+        return None;
+    }
+    // If `.git/HEAD` doesn't exist and `.git` is actually a file,
+    // then let's try to attempt to read it as a worktree. If it's
+    // a worktree, then its contents will look like this, e.g.:
+    //
+    //     gitdir: /home/andrew/astral/uv/main/.git/worktrees/pr2
+    //
+    // And the HEAD file we want to watch will be at:
+    //
+    //     /home/andrew/astral/uv/main/.git/worktrees/pr2/HEAD
+    let contents = fs::read_to_string(git_dir).ok()?;
+    let (label, worktree_path) = contents.split_once(':')?;
+    if label != "gitdir" {
+        return None;
+    }
+    let worktree_path = worktree_path.trim();
+    Some(PathBuf::from(worktree_path))
+}