diff --git a/src/utils.rs b/src/utils.rs
index edbfb61..7ccf8b4 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -40,12 +40,14 @@ pub fn to_element(value: Fq) -> Element {
 
 /// Download zkey from artifacts: https://snark-artifacts.pse.dev/
 pub fn download_zkey(depth: u16) -> Result<String, Box<dyn Error>> {
-    let base_url = "https://snark-artifacts.pse.dev/semaphore/latest/";
-    let filename = format!("semaphore-{}.zkey", depth);
+    let version = "4.0.0";
+    let base_url = format!("https://snark-artifacts.pse.dev/semaphore/{version}/");
+    let filename = format!("semaphore-{depth}.zkey");
+    let dest_filename = format!("semaphore-{version}-{depth}.zkey");
     let out_dir = std::env::temp_dir();
-    let dest_path = out_dir.join(filename.clone());
+    let dest_path = out_dir.join(dest_filename.clone());
     if !dest_path.exists() {
-        let url = format!("{}{}", base_url, filename);
+        let url = format!("{base_url}{filename}");
         let client = Client::new();
         let mut resp = client.get(&url).send()?.error_for_status()?;
         let mut out = File::create(&dest_path)?;