diff --git a/operational b/operational
index e1c4cd5cbce02dcf67b4008d6bf50cf5db3542b7..08bc57f305c867ee8672f6adaf662c3cd8d204a9 100644
--- a/operational
+++ b/operational
@@ -58,6 +58,31 @@ shared between zero-pinyin and ibus-pinyin.
 ** 2019-08-31 how to format C code? do it before git commit.
 see ~/c/gtk-im-module/, it uses myastyle-pre-commit-check in git pre-commit
 ~/bin/myastyle-pre-commit-check
+** 2020-02-16 how to create deb for distribution on apt repo?
+- on dev node, test deb, make sure it works.
+  git push
+- on debian 9 x86 and x64 build server,
+  git pull
+  ./create-deb.sh
+- upload deb to aptly node using scp.
+- create aptly distribution, snapshot and publish snapshot.
+
+  on aptly node,
+  aptly repo add d [FILE|DIR]...
+  aptly snapshot list
+  version=0.1
+  aptly snapshot create d-$version from repo d
+
+  # initial snapshot publish
+  # aptly publish snapshot \
+  #   -batch -gpg-key=apt@emacsos.com -passphrase-file=/etc/aptly_pass \
+  #   d-$version
+
+  # future publishes, switch publish to new snapshot
+  aptly publish switch \
+    -batch -gpg-key=apt@emacsos.com -passphrase-file=/etc/aptly_pass \
+    debian d-$version
+
 * later                                                               :entry:
 * current                                                             :entry:
 ** 
@@ -68,6 +93,20 @@ see ~/c/gtk-im-module/, it uses myastyle-pre-commit-check in git pre-commit
 - make the method work. use gobject property maybe.
 - set default flags to my flags. reflect this in UI/config file.
 * done                                                                :entry:
+** 2020-02-16 aptly publish fails
+- ERROR: prefix/distribution already used by another published repo
+  #+BEGIN_SRC sh
+    root@gcpsgp01:~/d#   aptly publish snapshot \
+    >     -batch -gpg-key=apt@emacsos.com -passphrase-file=/etc/aptly_pass \
+    >     d-$version
+    ERROR: prefix/distribution already used by another published repo: ./debian [amd64, i386] publishes {main: [d-0.1]: Snapshot from local repo [d]}
+  #+END_SRC
+
+  try unpublish old snapshot
+  aptly publish drop debian?
+
+  aptly publish switch -batch -gpg-key=apt@emacsos.com -passphrase-file=/etc/aptly_pass debian d-$version
+
 ** 2019-10-22 handle a an o en etc differently. only match exactly the character.
 no fuzzy matching or incomplete pinyin matching.