diff --git a/examples/op/common/build.rs b/examples/op/common/build.rs
index 1ccc8ac7..a60f3246 100644
--- a/examples/op/common/build.rs
+++ b/examples/op/common/build.rs
@@ -17,14 +17,18 @@ use std::{env, path::PathBuf, process::Command};
 fn main() {
     let manifest_dir =
         PathBuf::from(env::var_os("CARGO_MANIFEST_DIR").expect("CARGO_MANIFEST_DIR not set"));
-    let foundry_root = manifest_dir.join("../contracts/");
+
+    let mut foundry_root = manifest_dir.clone();
+    foundry_root.pop();
+    foundry_root.push("contracts");
     println!("foundry root: {}", foundry_root.display());
 
     // Make sure the Verifier.sol file is always compiled.
     let status = Command::new("forge")
         .arg("build")
         .arg("Verifier.sol")
-        .current_dir(foundry_root)
+        .arg("--root")
+        .arg(foundry_root)
         .status()
         .expect("failed to execute process");
     assert!(status.success(), "forge build failed");