diff --git a/com.emacsos.zero.ZeroPinyinService.service b/com.emacsos.zero.ZeroPinyinService.service
index 258d90f8b790f786d0053e841a2d941e7285d412..1ebc6dbaaf68ca71ac24a46a0051745c07510c08 100644
--- a/com.emacsos.zero.ZeroPinyinService.service
+++ b/com.emacsos.zero.ZeroPinyinService.service
@@ -1,3 +1,3 @@
 [D-BUS Service]
 Name=com.emacsos.zero.ZeroPinyinService
-Exec=/home/sylecn/projects/libpyzy/src/zero-pinyin-service/build/main
+Exec=/home/sylecn/projects/libpyzy/src/zero-pinyin-service/build/zero-pinyin-service
diff --git a/meson.build b/meson.build
index 74234a1fc6bb3e73bb9893c6609f648de05b3513..c882410d73dcac0f45fe23c0efb284afd95c524d 100644
--- a/meson.build
+++ b/meson.build
@@ -42,7 +42,7 @@ src = [
   'parse-pinyin.cpp',
   'zero-pinyin-service.c',
   'main.c']
-executable('main', src, dependencies: shared_dep)
+executable('zero-pinyin-service', src, dependencies: shared_dep)
 
 test('parse-pinyin',
   executable('parse-pinyin',
diff --git a/operational b/operational
new file mode 100644
index 0000000000000000000000000000000000000000..8ca17d2ee5339046a3cfb44a5261a3f1bacb790c
--- /dev/null
+++ b/operational
@@ -0,0 +1,46 @@
+* COMMENT -*- mode: org -*-
+#+Date: 2019-04-05
+Time-stamp: <2019-04-05>
+#+STARTUP: content
+* notes                                                               :entry:
+** 2019-04-05 zero-pinyin-service file structure			:doc:
+- zero-pinyin-service
+  - main.c
+    a console application based on glib and gio.
+    provides dbus service. see the zero-pinyin-service spec at
+    ~/c/gtk-im-module/operational :id001:
+  - zero-pinyin-service.h
+    zero-pinyin-service.c
+    zero-pinyin-service-test.c
+
+    contains the zero-pinyin-service dbus method C based implementation.
+  - parse-pinyin.h
+    parse-pinyin.cpp
+    parse-pinyin-test.cpp
+
+    contains utility functions based on code from libpyzyz. This should be
+    replaced eventually. I don't want to depend on libpyzy source code.
+
+- utilities
+  - test-sql.sh
+    a shell script to experiment SQL commands
+
+- data files
+  - meson.build
+
+    build script. used to create executable.
+
+  - com.emacsos.zero.ZeroPinyinService.service
+
+    dbus service definition file.
+
+    Should be copied to dbus service file dir /usr/share/dbus-1/services/
+
+    When dbus client try to talk to service, dbus session bus will start the
+    service app automatically.
+
+* later                                                               :entry:
+* current                                                             :entry:
+** 
+* done                                                                :entry:
+* wontfix                                                             :entry: