Convert json to csv with headers in jq

Is it possible to convert this json:

[
    {
        "bytes": 276697,
        "checked": false
    },
    {
        "bytes": 276697,
        "checked": false
    }
]

to a table WITH headers in jq? I've tried:

cat file.json | jq '.[] | join(",")'

but it omits headers:

"276697,false"
"276697,false"

it should be:

"bytes,checked"
"276697,false"
"276697,false"

I hoped that you can just run two commands:

cat file.json | jq '.[] | keys, .[] | join(",")'

but the second one fails:

"bytes,checked"
jq: error (at :64): Cannot iterate over null (null)

Ideally it would be simpler than this .