diff --git a/crates/sign/tests/it/pdf.rs b/crates/sign/tests/it/pdf.rs
index b7de2a4d3..3cad0fa75 100644
--- a/crates/sign/tests/it/pdf.rs
+++ b/crates/sign/tests/it/pdf.rs
@@ -665,12 +665,20 @@ trailer << /Root 1 0 R >>
     }
 }
 
+/// Held by every test that changes the user's keychain search list. Each saves the list, changes
+/// it and restores what it saved, so two at once could undo each other's temporary keychain or
+/// put back one already deleted.
+#[cfg(target_os = "macos")]
+static KEYCHAIN_SEARCH_LIST: std::sync::Mutex<()> = std::sync::Mutex::new(());
+
 /// Signing with Keychain identities, in a throwaway keychain file. Ignored by default: creating
 /// a keychain touches the user's keychain search list (restored afterwards).
 #[cfg(target_os = "macos")]
 #[test]
 #[ignore = "creates a temporary macOS keychain; run with --ignored"]
 fn signing_with_keychain_identities() {
+    // A test that failed while holding it leaves the list restored, so a poisoned lock is fine.
+    let _list = KEYCHAIN_SEARCH_LIST.lock().unwrap_or_else(std::sync::PoisonError::into_inner);
     use std::process::Command;
     let dir = std::env::temp_dir().join(format!("pdfcraft-keychain-{}", std::process::id()));
     std::fs::create_dir_all(&dir).unwrap();
@@ -683,7 +691,7 @@ fn signing_with_keychain_identities() {
     let restore = || {
         let mut args = vec!["list-keychains", "-d", "user", "-s"];
         args.extend(saved.iter().map(String::as_str));
-        sec(&args);
+        sec(&args)
     };
     restore();
     // Everything that can fail runs before the clean-up below.
@@ -705,9 +713,11 @@ fn signing_with_keychain_identities() {
             assert_eq!(s.status, Status::Valid, "{:?}", s.details);
         }
     }));
+    // The list first: it is what outlives the test if deleting the keychain goes wrong.
+    let restored = restore();
     sec(&["delete-keychain", k]);
-    restore();
     let _ = std::fs::remove_dir_all(&dir);
+    assert!(restored.status.success(), "the keychain search list wasn't restored: {}", String::from_utf8_lossy(&restored.stderr));
     result.unwrap();
 }
 
@@ -718,20 +728,28 @@ fn signing_with_keychain_identities() {
 #[test]
 #[ignore = "creates a temporary macOS keychain; run with --ignored"]
 fn keychain_identities_carry_their_issuers() {
+    // A test that failed while holding it leaves the list restored, so a poisoned lock is fine.
+    let _list = KEYCHAIN_SEARCH_LIST.lock().unwrap_or_else(std::sync::PoisonError::into_inner);
     use std::process::Command;
-    let dir = std::env::temp_dir().join(format!("pdfcraft-keychain-chain-{}", std::process::id()));
-    std::fs::create_dir_all(&dir).unwrap();
+    // The same path every run: trustd remembers which keychain file it found an issuer in, and
+    // after a run's keychain is deleted it keeps looking there, so a keychain at a new path
+    // would get an empty chain until that memory expires.
+    let dir = std::env::temp_dir().join("pdfcraft-keychain-chain");
     let kc = dir.join("test.keychain-db");
     let sec = |args: &[&str]| Command::new("security").args(args).output().unwrap();
+    let k = kc.to_str().unwrap();
+    // Left over by a run that was killed before its clean-up.
+    sec(&["delete-keychain", k]);
+    let _ = std::fs::remove_dir_all(&dir);
+    std::fs::create_dir_all(&dir).unwrap();
     let list = String::from_utf8(sec(&["list-keychains", "-d", "user"]).stdout).unwrap();
     let saved: Vec<String> = list.lines().map(|l| l.trim().trim_matches('"').to_string()).filter(|l| !l.is_empty()).collect();
-    let k = kc.to_str().unwrap();
     assert!(sec(&["create-keychain", "-p", "pc-test", k]).status.success());
     let set_list = |extra: Option<&str>| {
         let mut args = vec!["list-keychains", "-d", "user", "-s"];
         args.extend(saved.iter().map(String::as_str));
         args.extend(extra);
-        sec(&args);
+        sec(&args)
     };
     // macOS finds an identity's issuers in the keychains on the search list.
     set_list(Some(k));
@@ -742,15 +760,29 @@ fn keychain_identities_carry_their_issuers() {
         assert!(out.status.success(), "chain-legacy.p12: {}", String::from_utf8_lossy(&out.stderr));
         let listed = pdfcraft_sign::keychain::identities(Some(&kc)).unwrap();
         assert_eq!(listed.len(), 1, "{listed:?}");
-        let id = pdfcraft_sign::keychain::find(&pdfcraft_sign::keychain::reference(&listed[0].certificate)).unwrap();
+        // The Security framework caches the search list in-process and learns of `security
+        // list-keychains` asynchronously, so after another Keychain test it takes a moment to look
+        // in the new keychain.
+        let reference = pdfcraft_sign::keychain::reference(&listed[0].certificate);
+        let mut found = pdfcraft_sign::keychain::find(&reference);
+        for _ in 0..50 {
+            if found.is_ok() {
+                break;
+            }
+            std::thread::sleep(std::time::Duration::from_millis(100));
+            found = pdfcraft_sign::keychain::find(&reference);
+        }
+        let id = found.unwrap();
         let issuers: Vec<_> = id.chain.iter().map(|c| c.subject.common_name()).collect();
         assert_eq!(issuers, [Some("PrintCraft Test Root CA")]);
         let file = pkcs12::open(&data("chain.p12"), "test").unwrap();
         assert_eq!(id.chain.iter().map(|c| &c.raw).collect::<Vec<_>>(), file.chain.iter().map(|c| &c.raw).collect::<Vec<_>>());
     }));
+    // The list first: it is what outlives the test if deleting the keychain goes wrong.
+    let restored = set_list(None);
     sec(&["delete-keychain", k]);
-    set_list(None);
     let _ = std::fs::remove_dir_all(&dir);
+    assert!(restored.status.success(), "the keychain search list wasn't restored: {}", String::from_utf8_lossy(&restored.stderr));
     result.unwrap();
 }