ts-closure-transform

This package defines TypeScript code transformations that enable the serialize-closures package to serialize functions.

These transformations will rewrite all function definitions to include a special __closure property. The serializer uses that __closure property to figure out which variables are captured by the function.

How you inject this transform depends on the webpack loader you're using. For ts-loader you apply the following:

import { beforeTransform, afterTransform } from 'ts-closure-transform';
// ...
loader: 'ts-loader',
options: {
  getCustomTransformers: () => ({
    before: [beforeTransform()],
    after: [afterTransform()]
  })
}
// ...

Note that ts-closure-transform is strictly a dev dependency: there's no need to package it with your application.