babel.config.js

module.exports = function (api) {
    // Cache the returned value forever and don't call this function again.
    api.cache(true);
    const presets = [
        "@babel/preset-env",
        "@babel/preset-react"
    ];
    const plugins = [
        "@babel/plugin-transform-flow-strip-types",
        "@babel/plugin-proposal-export-default-from",
        "@babel/plugin-proposal-logical-assignment-operators",
        ["@babel/plugin-proposal-optional-chaining", { "loose": false }],
        ["@babel/plugin-proposal-pipeline-operator", { "proposal": "minimal" }],
        ["@babel/plugin-proposal-nullish-coalescing-operator", { "loose": false }],
        "@babel/plugin-proposal-do-expressions",

        ["@babel/plugin-proposal-decorators", { "legacy": true }],
        "@babel/plugin-proposal-function-sent",
        "@babel/plugin-proposal-export-namespace-from",
        "@babel/plugin-proposal-numeric-separator",
        "@babel/plugin-proposal-throw-expressions",

        "@babel/plugin-syntax-dynamic-import",
        "@babel/plugin-syntax-import-meta",
        ["@babel/plugin-proposal-class-properties", { "loose": false }],
        "@babel/plugin-proposal-json-strings"
    ];

    return {
        presets,
        plugins
    };
};