diff --git a/src/context/mod.rs b/src/context/mod.rs
index 79e471d0..6cce8b63 100644
--- a/src/context/mod.rs
+++ b/src/context/mod.rs
@@ -172,7 +172,7 @@ impl Context {
             Ok(RedisValue::StringBuffer(s)) => unsafe {
                 raw::RedisModule_ReplyWithStringBuffer.unwrap()(
                     self.ctx,
-                    s.as_ptr() as *const i8,
+                    s.as_ptr() as *const c_char,
                     s.len() as usize,
                 )
                 .into()