diff --git a/src/lib.rs b/src/lib.rs
index 1cb6577..164c62d 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -133,27 +133,26 @@ where
 ///
 /// Addresses are sorted according to the order on `OrdEmailAddress`.
 pub fn generate_sieve_script(redirects: AliasMap) -> String {
-    let mut script: String = "require [\"envelope\", \"copy\"];\n\n".to_string();
+    let mut script: String = "require [\"variables\", \"copy\", \"vnd.stalwart.expressions\"];\n\n".to_string();
     for (redirect, mut destinations) in redirects {
-        script += format!("if envelope :is \"to\" \"{}\" {{\n{}}}\n", redirect.0, {
-            let mut subscript: String = String::new();
-            destinations.sort();
-            for destination in destinations.iter().rev().skip(1).rev() {
-                subscript += format!("  redirect :copy \"{}\";\n", destination.0).as_str();
+        script += format!(
+            "if eval \"contains(recipients, '{}')\" {{\n{}}}\n",
+            redirect.0,
+            {
+                let mut subscript: String = String::new();
+                destinations.sort();
+                for destination in destinations.iter() {
+                    subscript += format!("  redirect :copy \"{}\";\n", destination.0).as_str();
+                }
+                subscript
             }
-            subscript
-                + format!(
-                    "  redirect \"{}\";\n",
-                    destinations.iter().next_back().unwrap().0
-                )
-                .as_str()
-        })
+        )
         .as_str();
     }
+    script += "discard;";
     script
 }
 
-
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -173,11 +172,12 @@ mod tests {
         let result = parse_alias_to_map(vec![AliasFile {
             content: read_lines("testdata/simple.aliases").unwrap(),
             default_domain: FQDN::from_str("example.com").unwrap(),
-        }]).unwrap();
+        }])
+        .unwrap();
         assert_eq!(result.len(), 4);
 
         for redirects in result.iter() {
             assert_eq!(redirects.1[0].0.to_string(), "me@example.org");
         }
     }
-}
\ No newline at end of file
+}