diff --git a/src/scheme.rs b/src/scheme.rs
index e26ebe379c8c4be54d21b4051a7f72551b17a4b5..b22c4513f684fea73e8abfdfc1bd70752829a166 100644
--- a/src/scheme.rs
+++ b/src/scheme.rs
@@ -8,6 +8,7 @@ use syscall::{error::*, flag::*, Stat, StatVfs, TimeSpec};
 use crate::{CallRequest, CallerCtx, OpenResult, Response};
 
 #[non_exhaustive]
+#[derive(Debug)]
 pub enum Op<'a> {
     Open {
         path: &'a str,