diff --git a/pxtarget.json b/pxtarget.json
index a53e8f7c..5cc9ff80 100644
--- a/pxtarget.json
+++ b/pxtarget.json
@@ -15,6 +15,7 @@
         "packages": true,
         "preferredPackages": [
             "Microsoft/pxt-neopixel",
+            "Microsoft/pxt-sonar",
             "Microsoft/pxt-max6675"
         ]
     },
@@ -34,7 +35,7 @@
         },
         "files": {
             "main.blocks": "<xml xmlns=\"http://www.w3.org/1999/xhtml\">\n<block type=\"device_forever\">\n<statement name=\"HANDLER\">\n<block type=\"device_show_leds\">\n<field name=\"LED00\">FALSE</field>\n<field name=\"LED10\">FALSE</field>\n<field name=\"LED20\">FALSE</field>\n<field name=\"LED30\">FALSE</field>\n<field name=\"LED40\">FALSE</field>\n<field name=\"LED01\">FALSE</field>\n<field name=\"LED11\">TRUE</field>\n<field name=\"LED21\">FALSE</field>\n<field name=\"LED31\">TRUE</field>\n<field name=\"LED41\">FALSE</field>\n<field name=\"LED02\">FALSE</field>\n<field name=\"LED12\">FALSE</field>\n<field name=\"LED22\">FALSE</field>\n<field name=\"LED32\">FALSE</field>\n<field name=\"LED42\">FALSE</field>\n<field name=\"LED03\">TRUE</field>\n<field name=\"LED13\">FALSE</field>\n<field name=\"LED23\">FALSE</field>\n<field name=\"LED33\">FALSE</field>\n<field name=\"LED43\">TRUE</field>\n<field name=\"LED04\">FALSE</field>\n<field name=\"LED14\">TRUE</field>\n<field name=\"LED24\">TRUE</field>\n<field name=\"LED34\">TRUE</field>\n<field name=\"LED44\">FALSE</field>\n<next>\n<block type=\"device_show_leds\">\n<field name=\"LED00\">FALSE</field>\n<field name=\"LED10\">FALSE</field>\n<field name=\"LED20\">FALSE</field>\n<field name=\"LED30\">FALSE</field>\n<field name=\"LED40\">FALSE</field>\n<field name=\"LED01\">FALSE</field>\n<field name=\"LED11\">FALSE</field>\n<field name=\"LED21\">FALSE</field>\n<field name=\"LED31\">FALSE</field>\n<field name=\"LED41\">FALSE</field>\n<field name=\"LED02\">FALSE</field>\n<field name=\"LED12\">FALSE</field>\n<field name=\"LED22\">FALSE</field>\n<field name=\"LED32\">FALSE</field>\n<field name=\"LED42\">FALSE</field>\n<field name=\"LED03\">FALSE</field>\n<field name=\"LED13\">FALSE</field>\n<field name=\"LED23\">FALSE</field>\n<field name=\"LED33\">FALSE</field>\n<field name=\"LED43\">FALSE</field>\n<field name=\"LED04\">FALSE</field>\n<field name=\"LED14\">FALSE</field>\n<field name=\"LED24\">FALSE</field>\n<field name=\"LED34\">FALSE</field>\n<field name=\"LED44\">FALSE</field>\n</block>\n</next>\n</block>\n</statement>\n</block>\n</xml>",
-            "main.ts": "\r\n"
+            "main.ts": "basic.forever(() => {\r\n    basic.showLeds(`\r\n        . # . # .\r\n        # . # . #\r\n        # . . . #\r\n        . # . # .\r\n        . . # . .\r\n        `)\r\n    basic.showLeds(`\r\n        . . . . .\r\n        . . . . .\r\n        . . . . .\r\n        . . . . .\r\n        . . . . .\r\n        `)\r\n})\r\n"
         }
     },
     "tsprj": {