{
    "$schema": "https://vega.github.io/schema/vega-lite/v4.json",
    "config": {
        "scale": {
            "bandPaddingInner": 0,
            "bandPaddingOuter": 0,
            "xReverse": false
        },
        "text": {
            "baseline": "middle"
        }
    },
    "data": {
        "url": "https://vega.github.io/vega-lite/data/cars.json"
    },
    "description": "Layering text over 'heatmap'",
    "encoding": {
        "x": {
            "field": "Cylinders",
            "type": "ordinal"
        },
        "y": {
            "field": "Origin",
            "type": "ordinal"
        }
    },
    "layer": [
        {
            "encoding": {
                "color": {
                    "aggregate": "count",
                    "field": "*",
                    "type": "quantitative"
                }
            },
            "mark": "rect"
        },
        {
            "encoding": {
                "color": {
                    "value": "white"
                },
                "text": {
                    "aggregate": "count",
                    "field": "*",
                    "type": "quantitative"
                }
            },
            "mark": "text"
        }
    ]
}