diff --git a/crates/precompiles/src/error.rs b/crates/precompiles/src/error.rs
index 304c21f87c..d9a324027d 100644
--- a/crates/precompiles/src/error.rs
+++ b/crates/precompiles/src/error.rs
@@ -95,7 +95,8 @@ pub fn add_errors_to_registry<T: SolInterface>(
     let converter = Arc::new(converter);
     for selector in T::selectors() {
         let converter = Arc::clone(&converter);
-        registry.insert(
+
+        let old_selector = registry.insert(
             selector.into(),
             Box::new(move |data: &[u8]| {
                 T::abi_decode(data)
@@ -106,6 +107,7 @@ pub fn add_errors_to_registry<T: SolInterface>(
                     })
             }),
         );
+        debug_assert!(old_selector.is_none(), "Duplicate selector {selector:x?}");
     }
 }
 
@@ -254,3 +256,14 @@ impl<T> IntoPrecompileResult<T> for TempoPrecompileError {
         Ok(PrecompileOutput::new_reverted(gas, bytes))
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use crate::error::error_decoder_registry;
+
+    // Test that initializes the error decoder registry and fails if there are any duplicates.
+    #[test]
+    fn test_error_decoder_registry_init() {
+        error_decoder_registry();
+    }
+}