diff --git a/.drone.yml b/.drone.yml
index c7ca7a3..7dbc746 100644
--- a/.drone.yml
+++ b/.drone.yml
@@ -11,9 +11,11 @@ pipeline:
     environment:
       - GOPATH=/go
     commands:
+      - make deps
       - make vet
       - make lint
       - make build
+      - make embedmd
       - coverage all
       # send coverage report
       - make coverage
diff --git a/.drone.yml.sig b/.drone.yml.sig
index 7140d11..be0cadc 100644
--- a/.drone.yml.sig
+++ b/.drone.yml.sig
@@ -1 +1 @@
-eyJhbGciOiJIUzI1NiJ9.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.iN00BApOMrBjB45OwRNmWh438xJMxFrTmzsx6Eeu-NY
\ No newline at end of file
+eyJhbGciOiJIUzI1NiJ9.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.7ieZ2R6o0gwph45wl0Dbu9RRm_H36d0b9_fw38tqLOU
\ No newline at end of file
diff --git a/.travis.yml b/.travis.yml
index 800576f..8db1e73 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -9,7 +9,7 @@ go:
   - 1.6.x
   - 1.7.x
   - 1.8.x
-  - tip
+  - master
 
 env:
   global:
@@ -18,6 +18,8 @@ env:
     - secure: 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
 
 script:
+  - make deps
+  - make embedmd
   - make vet
   - make lint
   - make test
diff --git a/Makefile b/Makefile
index d4b347d..a9122a5 100644
--- a/Makefile
+++ b/Makefile
@@ -44,6 +44,12 @@ fmt:
 vet:
 	go vet $(PACKAGES)
 
+deps:
+	go get github.com/campoy/embedmd
+
+embedmd:
+	embedmd -d *.md
+
 errcheck:
 	@which errcheck > /dev/null; if [ $$? -ne 0 ]; then \
 		go get -u github.com/kisielk/errcheck; \
diff --git a/README.md b/README.md
index 684511f..9b24adf 100644
--- a/README.md
+++ b/README.md
@@ -54,13 +54,12 @@ A push notification micro server using [Gin](https://github.com/gin-gonic/gin) f
 
 See the [YAML config example](config/config.yml):
 
+[embedmd]:# (config/config.yml yaml)
 ```yaml
 core:
   port: "8088"
-  # default worker number is runtime.NumCPU()
-  worker_num: 0
-  # default queue number is 8192
-  queue_num: 0
+  worker_num: 0 # default worker number is runtime.NumCPU()
+  queue_num: 0 # default queue number is 8192
   max_notification: 100
   mode: "release"
   ssl: false
@@ -68,7 +67,7 @@ core:
   key_path: "key.pem"
   http_proxy: "" # only working for GCM server
   pid:
-    enabled: true
+    enabled: false
     path: "gorush.pid"
     override: true
 
diff --git a/config/config.yml b/config/config.yml
index b387c18..f5378da 100644
--- a/config/config.yml
+++ b/config/config.yml
@@ -1,15 +1,13 @@
 core:
   port: "8088"
-  # default worker number is runtime.NumCPU()
-  worker_num: 0
-  # default queue number is 8192
-  queue_num: 0
+  worker_num: 0 # default worker number is runtime.NumCPU()
+  queue_num: 0 # default queue number is 8192
   max_notification: 100
   mode: "release"
   ssl: false
   cert_path: "cert.pem"
   key_path: "key.pem"
-  http_proxy: ""
+  http_proxy: "" # only working for GCM server
   pid:
     enabled: false
     path: "gorush.pid"
@@ -26,25 +24,25 @@ api:
 android:
   enabled: true
   apikey: "YOUR_API_KEY"
-  max_retry: 0
+  max_retry: 0 # resend fail notification, default value zero is disabled
 
 ios:
   enabled: false
   key_path: "key.pem"
-  password: ""
+  password: "" # certificate password, default as empty string.
   production: false
-  max_retry: 0
+  max_retry: 0 # resend fail notification, default value zero is disabled
 
 log:
   format: "string" # string or json
-  access_log: "stdout"
+  access_log: "stdout" # stdout: output to console, or define log path like "log/access_log"
   access_level: "debug"
-  error_log: "stderr"
+  error_log: "stderr" # stderr: output to console, or define log path like "log/error_log"
   error_level: "error"
   hide_token: true
 
 stat:
-  engine: "memory"
+  engine: "memory" # support memory, redis, boltdb, buntdb or leveldb
   redis:
     addr: "localhost:6379"
     password: ""