diff --git a/environment.nix b/environment.nix
index 099f271..37c8992 100644
--- a/environment.nix
+++ b/environment.nix
@@ -54,4 +54,16 @@
     promptInit = builtins.readFile ./bash-prompt.sh;
     interactiveShellInit = builtins.readFile ./bash-interactive-init.sh;
   };
+
+  # https://wiki.mozilla.org/Security/Guidelines/OpenSSH#Modern
+  programs.ssh.extraConfig = ''
+    # Ensure KnownHosts are unreadable if leaked - it is otherwise easier to know which hosts your keys have access to.
+    HashKnownHosts yes
+    # Host keys the client accepts - order here is honored by OpenSSH
+    HostKeyAlgorithms ssh-ed25519-cert-v01@openssh.com,ssh-rsa-cert-v01@openssh.com,ssh-ed25519,ssh-rsa,ecdsa-sha2-nistp521-cert-v01@openssh.com,ecdsa-sha2-nistp384-cert-v01@openssh.com,ecdsa-sha2-nistp256-cert-v01@openssh.com,ecdsa-sha2-nistp521,ecdsa-sha2-nistp384,ecdsa-sha2-nistp256
+
+    KexAlgorithms curve25519-sha256@libssh.org,ecdh-sha2-nistp521,ecdh-sha2-nistp256,ecdh-sha2-nistp384,diffie-hellman-group-exchange-sha256
+    MACs hmac-sha2-512-etm@openssh.com,hmac-sha2-256-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-512,hmac-sha2-256,umac-128@openssh.com
+    Ciphers chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com,aes256-ctr,aes192-ctr,aes128-ctr
+  '';
 }