How to style a JSON block in Github Wiki?

Some color-syntaxing enrichment can be applied with the following blockcode syntax

```json
Here goes your json object definition
```

Note: This won't prettify the json representation. To do so, one can previously rely on an external service such as jsbeautifier.org and paste the prettified result in the wiki.

```javascript
{ "some": "json" }
```

I tried using json but didn't like the way it looked. javascript looks a bit more pleasing to my eye.