在Go中实现规则引擎框架：Rulio

I am trying to use Rulio (rule engine written in Go). The documentation is not very informative and I am not sure how to implement rules having more than one conditions. Anyone suggestions? This is the rule JSON, I manage to construct but it doesn't produce the correct result.

{
    "location": "here",
    "rule": {
        "when": {
            "pattern": {
                "wants": "?x",
                "love":"?y"
            }
        },
        "condition": {
            "pattern": {
                "have": "?x"
            }
        },
        "action": {
            "code": "var msg = 'eat ' + x; console.log(msg); msg;"
        }
    }
}

Fact

{
    "location": "here",
    "fact":{"have":"tacos"}
}

For testing, if I pass

    "location": "here",
    "event": {"love":"tacos"}
}

I get an empty set. The expected result should be "eat tacos"