Pattern for sending complex classes over SSR boundary?

[Cobertos]

Anyone have any good patterns for sending classes over the SSR boundary, or working with the objects you can send over?

When sending something from server-side to client-side, it get's stringified (with @nuxt/devalue), losing all the class info (methods, equivalence, etc) in the process.

I've started adding static methods to all my classes to do things that take the "plain" object and do stuff to it.

An example

export class Product {
  constructor(obj) {
    Object.assign(this, obj);
    // Post process the data from API
    this.price = this.price ? parseFloat(this.price) : undefined; // price is a string :c
    _assert(!Number.isNaN(this.price), `Price '${obj.price}' should parse as a float or fail`);
  }

  static formatPrice(product) {
    if (product === undefined || product === null) {
      return '';
    }
    return `$${product.price.toFixed(2)}`;
  }

How do you normally handle this?