my custom babel preset

babel.preset.js

const preset = buildPreset()
Object.defineProperty(preset, "buildPreset", {
    configurable: true,
    writable: true,
    enumerable: false,
    value: buildPreset
})
module.exports = preset

function buildPreset(opts = {}) {
    const {env = "node"} = opts;

    const browser = env === "browser"
    const node = env === "node"

    const isProduction = process.env.NODE_ENV === 'production'

    const presets = [
        ["env", {
            modules: !browser && "commonjs",
            loose: true,
            targets: browser ? {
                "chrome": 55
            } : {
                node: "current"
            }
        }],
        "react"
    ]

    const plugins = [
        ["transform-async-to-module-method", {
            module: "bluebird-co",
            method: "coroutine"
        }],
        "transform-class-properties",
        "transform-decorators-legacy",
        ["transform-runtime"],
        ["transform-object-rest-spread", {
            useBuiltIns: true
        }],
        !browser && ["system-import-transformer", {
            modules: "commonjs"
        }],
        (browser && !isProduction) && "react-hot-loader/babel"
    ]


    if (browser && isProduction) {
        presets.push(
            "babili",
            "react-optimize"
        )
        plugins.push(
            "minify-empty-function",
            "transform-remove-console",
            "transform-remove-debugger",
            "transform-node-env-inline",
            "transform-inline-environment-variables",
            "transform-react-inline-elements"
        )
    }

    return {
        presets: presets.filter(Boolean),
        plugins: plugins.filter(Boolean),
    }
}