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This package contains Vue bindings for @leanjs/core runtime. These Vue bindings provide idiomatic type-safe access to your LeanJS runtime.


yarn add @leanjs/vue


1 . Create your custom useSharedState composable. This will add type-safety to your useSharedState composable based on your instance of LeanJS runtime.

// runtime-vue.ts
// Pro-tip: move this file to its own package, see examples/coolest-todos/packages/runtime-vue

const defaultState = {
locale: "en", // define your default state accordingly, this is just an example

// configureRuntime is a generic TS function (if you use TypeScript)
// handy if the types that you want don't match the inferred types from defaultState
export const { createRuntime } = configureRuntime(defaultState)({
onError: () => throw new Error("🔥 log this properly!")

export const { useSharedState } = createRuntimeBindings(createRuntime);

⚠️ Why is useSharedState not a generic function instead of using createRuntimeBindings to infer and return a typed useSharedState?

We want useSharedState to have custom TypeScript types based on the runtime used by a group of micro-apps in the same micro-frontend architecture. We don't want to give the consumers of useSharedState the ability to change these types because that could create inconsistencies between different micro-apps that share the same runtime.

2 . Provide a runtime at the root of your app, e.g.

import { createApp } from "vue";
// Pro-tip: move your ./runtime-vue file to its own package, see examples/coolest-todos/packages/runtime-vue
import { createRuntime } from "./runtime-vue";

const runtime = createRuntime();
const app = createApp(App);

app.provide("runtime", runtime);

3 . Use your useSharedState in your app, e.g.

<h1>Locale is {{ locale }}</h1>
import { useSharedState } from "./runtime-vue";
export default {
name: "App",
setup() {
return useSharedState("locale");


To use any of the following, you must first call createRuntimeBindings. Read the usage section above for more info.


Composable to get the current state of one or many shared state properties. Types:

type useSharedState = <
MyState extends Record<string, any>,
Prop extends keyof MyState
| Prop[]
| {
prop: Prop;
loader?: () => MyState[Prop] | Promise<MyState[Prop]>;
deep?: boolean;
) => Record<Prop, Ref<MyState[Prop]>>;


You have a full example in the following files:

  • examples/coolest-todos/packages/runtime-vue/src/index.ts
  • examples/coolest-todos/micros/profile-reset/src/components/App.vue


Do you have any issues with this package? Please file an issue.

Feedback or questions

Send me a tweet at @alex_lobera with any feedback or questions 🙏.