serialize-killer/jest.config.js

Make your objects unserializable.

/** @type {import('ts-jest').JestConfigWithTsJest} */
module.exports = {
  preset: 'ts-jest',
  testEnvironment: 'node',
  testPathIgnorePatterns: ['/node_modules/', '<rootDir>/lib/'],
  clearMocks: true,
  transform: {
    '^.+\\.tsx?$': [
      'ts-jest',
      {
        isolatedModules: true,
      },
    ],
  },
};