WireMock

A single-node WireMock container — the closest thing the TypeScript ecosystem has to WireMock's usual in-process embedding on the JVM: a real WireMock server, isolated per test run, reachable over HTTP.

Default image: wiremock/wiremock:3.13.2Exposed port: 8080Wait strategy: Wait.forHttp("/__admin/health").forPort(8080)

Member	Returns
WireMockContainer.start(image?)	Promise<WireMockContainer> — boots the container
.baseUrl	The stubbed API's base URL
.adminUrl	The admin API's base URL (/__admin/...)

Example

import { WireMockContainer } from "rightsize/modules";

await using wiremock = await WireMockContainer.start();

await fetch(`${wiremock.adminUrl}/mappings`, {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({
    request: { method: "GET", url: "/hello" },
    response: { status: 200, jsonBody: { message: "hi" } },
  }),
});

console.log(await (await fetch(`${wiremock.baseUrl}/hello`)).json()); // { message: "hi" }

Backend notes

None — WireMock boots and serves cleanly on both backends with no special handling; /__admin/health (shipped since 3.x) is preferred over polling /__admin/mappings for readiness, since it reads as "am I healthy" rather than "list of stubs so far."