Object.defineProperty()

const obj = {};
// 1. Using a null prototype: no inherited properties
const descriptor = Object.create(null);
descriptor.value = "static";

// not enumerable, not configurable, not writable as defaults
Object.defineProperty(obj, "key", descriptor);

// 2. Being explicit by using a throw-away object literal with all attributes present
Object.defineProperty(obj, "key2", {
  enumerable: false,
  configurable: false,
  writable: false,
  value: "static",
});

// 3. Recycling same object
function withValue(value) {
  const d =
    withValue.d ||
    (withValue.d = {
      enumerable: false,
      writable: false,
      configurable: false,
      value,
    });

  // avoiding duplicate operation for assigning value
  if (d.value !== value) d.value = value;

  return d;
}
// and
Object.defineProperty(obj, "key", withValue("static"));

// if freeze is available, prevents adding or
// removing the object prototype properties
// (value, get, set, enumerable, writable, configurable)
(Object.freeze || Object)(Object.prototype);