diff --git a/card-functionality/src/tests.rs b/card-functionality/src/tests.rs
index 93d115c..5f0fe12 100644
--- a/card-functionality/src/tests.rs
+++ b/card-functionality/src/tests.rs
@@ -65,14 +65,18 @@ pub fn test_decrypt(
         "test_decrypt needs filenames for 'cert' and 'encrypted'"
     );
 
-    let cert = Cert::from_str(param[0])?;
     let msg = param[1].to_string();
 
     pgpt.verify_pw1_user(b"123456")?;
 
     let p = StandardPolicy::new();
 
-    let res = openpgp_card_sequoia::util::decrypt(&mut pgpt, &cert, msg.into_bytes(), &|| {}, &p)?;
+    let mut open = Open::new(pgpt)?;
+
+    let mut user = open.user_card().unwrap();
+    let d = user.decryptor(&|| {})?;
+
+    let res = openpgp_card_sequoia::util::decrypt(d, msg.into_bytes(), &p)?;
     let plain = String::from_utf8_lossy(&res);
 
     assert_eq!(plain, "Hello world!\n");
@@ -94,8 +98,13 @@ pub fn test_sign(
 
     let cert = Cert::from_str(param[0])?;
 
+    let mut open = Open::new(pgpt)?;
+
+    let mut sign = open.signing_card().unwrap();
+    let s = sign.signer(&|| {})?;
+
     let msg = "Hello world, I am signed.";
-    let sig = openpgp_card_sequoia::util::sign(&mut pgpt, &cert, &mut msg.as_bytes(), &|| {})?;
+    let sig = openpgp_card_sequoia::util::sign(s, &mut msg.as_bytes())?;
 
     // validate sig
     assert!(util::verify_sig(&cert, msg.as_bytes(), sig.as_bytes())?);
diff --git a/openpgp-card-examples/src/bin/decrypt.rs b/openpgp-card-examples/src/bin/decrypt.rs
index 1a70905..62352c0 100644
--- a/openpgp-card-examples/src/bin/decrypt.rs
+++ b/openpgp-card-examples/src/bin/decrypt.rs
@@ -7,20 +7,18 @@ use openpgp_card_sequoia::card::Open;
 
 use openpgp::parse::{stream::DecryptorBuilder, Parse};
 use openpgp::policy::StandardPolicy;
-use openpgp::Cert;
 use sequoia_openpgp as openpgp;
 
 fn main() -> Result<(), Box<dyn std::error::Error>> {
     let args = std::env::args().collect::<Vec<_>>();
 
-    if args.len() < 3 {
-        eprintln!("Usage: decrypt card-ident pin-file cert-file");
+    if args.len() < 2 {
+        eprintln!("Usage: decrypt card-ident pin-file");
         return Ok(());
     }
 
     let card_ident = &args[0];
     let pin_file = &args[1];
-    let cert_file = &args[2];
 
     let mut card = PcscBackend::open_by_ident(card_ident, None)?;
     let mut pgp = OpenPgp::new(&mut card);
@@ -34,10 +32,8 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     let mut user = open.user_card().unwrap();
 
     let p = StandardPolicy::new();
-    let cert = Cert::from_file(cert_file)?;
-    let d = user.decryptor(&cert, &|| {
-        println!("Touch confirmation needed for decryption")
-    })?;
+
+    let d = user.decryptor(&|| println!("Touch confirmation needed for decryption"))?;
     let stdin = std::io::stdin();
 
     let mut stdout = std::io::stdout();
diff --git a/openpgp-card-examples/src/bin/detach-sign.rs b/openpgp-card-examples/src/bin/detach-sign.rs
index 5091273..f78ddb7 100644
--- a/openpgp-card-examples/src/bin/detach-sign.rs
+++ b/openpgp-card-examples/src/bin/detach-sign.rs
@@ -5,22 +5,19 @@ use openpgp_card::OpenPgp;
 use openpgp_card_pcsc::PcscBackend;
 use openpgp_card_sequoia::card::Open;
 
-use openpgp::parse::Parse;
 use openpgp::serialize::stream::{Armorer, Message, Signer};
-use openpgp::Cert;
 use sequoia_openpgp as openpgp;
 
 fn main() -> Result<(), Box<dyn std::error::Error>> {
     let args = std::env::args().collect::<Vec<_>>();
 
-    if args.len() < 3 {
-        eprintln!("Usage: detach-sign card-ident pin-file cert-file");
+    if args.len() < 2 {
+        eprintln!("Usage: detach-sign card-ident pin-file");
         return Ok(());
     }
 
     let card_ident = &args[0];
     let pin_file = &args[1];
-    let cert_file = &args[2];
 
     let mut card = PcscBackend::open_by_ident(card_ident, None)?;
     let mut pgp = OpenPgp::new(&mut card);
@@ -32,9 +29,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     open.verify_user_for_signing(&pin)?;
 
     let mut sign = open.signing_card().unwrap();
-
-    let cert = Cert::from_file(cert_file)?;
-    let s = sign.signer(&cert, &|| println!("Touch confirmation needed for signing"))?;
+    let s = sign.signer(&|| println!("Touch confirmation needed for signing"))?;
 
     let stdout = std::io::stdout();