diff --git a/server/src/worktree.rs b/server/src/worktree.rs
index 3dc024e..e2b817d 100644
--- a/server/src/worktree.rs
+++ b/server/src/worktree.rs
@@ -160,56 +160,31 @@ fn create_worktree_sync(
 /// This prevents pipeline file moves (upcoming → current → qa → merge → archived)
 /// from being committed on feature branches, which avoids rename/delete merge
 /// conflicts when merging back to master.
+///
+/// Uses `git sparse-checkout set --no-cone` which correctly isolates the
+/// config to the worktree without polluting the main checkout's config.
 fn configure_sparse_checkout(wt_path: &Path) -> Result<(), String> {
-    // Enable worktree-specific config so sparse checkout settings don't leak
-    // to the main checkout or other worktrees.
-    let _ = Command::new("git")
-        .args(["config", "extensions.worktreeConfig", "true"])
-        .current_dir(wt_path)
-        .output();
-
-    // Enable sparse checkout for THIS worktree only (--worktree flag).
-    // Without --worktree, this writes to the shared .git/config and
-    // enables sparse checkout on the main checkout too.
+    // `git sparse-checkout set --no-cone` handles everything:
+    // - Enables core.sparseCheckout for this worktree only
+    // - Writes the pattern file to the correct worktree-specific git dir
+    // - Updates the working tree
+    //
+    // The '!' prefix excludes .story_kit/work/ while '/*' includes everything else.
     let output = Command::new("git")
-        .args(["config", "--worktree", "core.sparseCheckout", "true"])
+        .args([
+            "sparse-checkout",
+            "set",
+            "--no-cone",
+            "/*",
+            "!.story_kit/work/",
+        ])
         .current_dir(wt_path)
         .output()
-        .map_err(|e| format!("sparse-checkout config: {e}"))?;
+        .map_err(|e| format!("git sparse-checkout set: {e}"))?;
 
     if !output.status.success() {
         let stderr = String::from_utf8_lossy(&output.stderr);
-        return Err(format!("sparse-checkout config failed: {stderr}"));
-    }
-
-    // Resolve the actual git dir (worktrees use a .git file pointing elsewhere)
-    let git_dir_output = Command::new("git")
-        .args(["rev-parse", "--git-dir"])
-        .current_dir(wt_path)
-        .output()
-        .map_err(|e| format!("git rev-parse --git-dir: {e}"))?;
-
-    let git_dir = PathBuf::from(
-        String::from_utf8_lossy(&git_dir_output.stdout).trim().to_string(),
-    );
-
-    // Write sparse-checkout patterns: include everything, exclude .story_kit/work/
-    let info_dir = git_dir.join("info");
-    std::fs::create_dir_all(&info_dir)
-        .map_err(|e| format!("Create sparse-checkout dir: {e}"))?;
-    std::fs::write(info_dir.join("sparse-checkout"), "/*\n!.story_kit/work/\n")
-        .map_err(|e| format!("Write sparse-checkout: {e}"))?;
-
-    // Re-read the working tree to apply sparse checkout rules
-    let output = Command::new("git")
-        .args(["read-tree", "-mu", "HEAD"])
-        .current_dir(wt_path)
-        .output()
-        .map_err(|e| format!("git read-tree: {e}"))?;
-
-    if !output.status.success() {
-        let stderr = String::from_utf8_lossy(&output.stderr);
-        return Err(format!("git read-tree failed: {stderr}"));
+        return Err(format!("git sparse-checkout set failed: {stderr}"));
     }
 
     Ok(())