diff --git a/docker b/docker
index 7e499dd..16870bf 100644
--- a/docker
+++ b/docker
@@ -33,3 +33,6 @@ docker images
 
 # To remove all untagged images:
 docker rmi $(docker images | grep "^<none>" | awk "{print $3}")
+
+# To remove all volumes not used by at least one container:
+docker volume prune
diff --git a/ssh-add b/ssh-add
index 9195c5a..f1758e4 100644
--- a/ssh-add
+++ b/ssh-add
@@ -1,5 +1,5 @@
 ---
-tags [ ssh ]
+tags: [ ssh ]
 ---
 # To add private key:
 ssh-add <keyfile>
@@ -7,6 +7,9 @@ ssh-add <keyfile>
 # To load resident keys from FIDO2 authenticator:
 ssh-add -K
 
+# To store a GitHub SSH passphrase in your keychain:
+ssh-add -K ~/.ssh/github_rsa
+
 # To list all public keys:
 ssh-add -L