Hanami JSON Oddity I don't understand

Problem.txt

The repo for the code is at (pretty basic):
https://github.com/daneb/hanami_json_oddity

I understand the best approach is to use a controller here and not the view. 
But I am trying to understand the behaviour of what I am seeing.

In my view, when I take my hash and .to_json it, the final result from the HTTP GET is:
{ status: "success", data: { get: { message: 'Created new session via registration', session_id: session_id } }}.to_json

{"status":"success","data":{"get":{"message":"Created new session via registration","session_id":12}}}

When I remove .to_json from the view and apply it to the hash in the template it works:
<%= get_sample_hash.to_json %>

{
    "data": {
        "get": {
            "message": "Created new session via registration",
            "session_id": 12
        }
    },
    "status": "success"
}

What am I missing?

From Gitter:
accuser 11:40
@daneb The string returned by the view is considered unsafe, and is being escaped. To avoid this, use _raw.