diff --git a/README.md b/README.md
index d2df1f4..10ce335 100644
--- a/README.md
+++ b/README.md
@@ -10,10 +10,10 @@ usage decently.
 [gemini]: https://gemini.circumlunar.space/
 [amfora]: https://github.com/makeworld-the-better-one/amfora
 
-If you are interested in Gemini and looking for a client, I recommend trying a
-graphical one like the excellent [Lagrange][lagrange] or [Kristall][kristall],
-or Amfora if you're feeling more at home in the terminal. Bebop won't attempt
-to support every feature other clients might have.
+If you are interested in Gemini and looking for a desktop/laptop client, I
+recommend trying a graphical one like the excellent [Lagrange][lagrange] or
+[Kristall][kristall], or Amfora if you're feeling more at home in the terminal.
+Bebop won't attempt to support every feature other clients might have.
 
 [lagrange]: https://git.skyjake.fi/skyjake/lagrange
 [kristall]: https://kristall.random-projects.net/
diff --git a/bebop/__main__.py b/bebop/__main__.py
index 360a45c..9c7c8d2 100644
--- a/bebop/__main__.py
+++ b/bebop/__main__.py
@@ -1,7 +1,9 @@
 import argparse
+import os
 
 from bebop.browser import Browser
-from bebop.tofu import load_cert_stash
+from bebop.fs import get_user_data_path
+from bebop.tofu import load_cert_stash, save_cert_stash
 
 
 def main():
@@ -14,8 +16,16 @@ def main():
     else:
         start_url = None
 
-    cert_stash = load_cert_stash("/tmp/stash")
-    Browser(cert_stash).run(start_url=start_url)
+    user_data_path = get_user_data_path()
+    if not user_data_path.exists():
+        user_data_path.mkdir()
+
+    cert_stash_path = user_data_path / "known_hosts.txt"
+    cert_stash = load_cert_stash(cert_stash_path)
+    try:
+        Browser(cert_stash).run(start_url=start_url)
+    finally:
+        save_cert_stash(cert_stash, cert_stash_path)
 
 
 main()
diff --git a/bebop/tofu.py b/bebop/tofu.py
index 1ab8080..df0419b 100644
--- a/bebop/tofu.py
+++ b/bebop/tofu.py
@@ -42,6 +42,20 @@ def load_cert_stash(stash_path):
     return stash
 
 
+def save_cert_stash(stash, stash_path):
+    """Save the certificate stash."""
+    try:
+        with open(stash_path, "wt") as stash_file:
+            for name, entry in stash.values():
+                algo, fingerprint, timestamp, is_permanent = entry
+                if not is_permanent:
+                    continue
+                entry_line = f"{name} {algo} {fingerprint} {timestamp}\n"
+                stash_path.write(entry_line)
+    except (OSError, ValueError):
+        pass
+
+
 class CertStatus(Enum):
     """Value returned by validate_cert."""
     # Cert is valid: proceed.