tweak syntax highlighting
diff --git a/src/docs/develop.md b/src/docs/develop.md
index f1c8bb5..2300712 100644
--- a/src/docs/develop.md
+++ b/src/docs/develop.md
@@ -20,7 +20,7 @@
 
 To retrieve the code using git:
 
-```
+``` shell
 $ git clone https://gitbox.apache.org/repos/asf/incubator-annotator.git apache-annotator
 ```
 
@@ -47,7 +47,7 @@
 
 To run a webserver running [the demo](https://annotator.apache.org/demo/):
 
-```
+``` shell
 $ yarn start
 ```