Nuxt quickstart

1. Install hypertune

Once you have a Nuxt application ready, install Hypertune's JavaScript SDK:

npm

npm install hypertune

yarn

yarn add hypertune

pnpm

pnpm add hypertune

2. Set environment variables

Define the following environment variables in your .env file:

.env

HYPERTUNE_TOKEN=token
HYPERTUNE_FRAMEWORK=vue
HYPERTUNE_OUTPUT_DIRECTORY_PATH=generated

Replace token with your main project token which you can find in the Settings tab of your project.

3. Generate the client

Generate a type-safe client to access your flags by running:

npm

npx hypertune

yarn

yarn hypertune

pnpm

pnpm hypertune

4. Use the client

Add hypertuneToken to runtimeConfig in your nuxt.config.ts :

nuxt.config.ts

export default defineNuxtConfig({
  runtimeConfig: {
    public: {
      hypertuneToken: process.env.HYPERTUNE_TOKEN!,
    },
  },
});

Then add a plugin for Hypertune to your app:

plugins/hypertune.ts

import {
  type DehydratedState,
  type RootArgs,
  createSourceForServerOnly,
} from '~/generated/hypertune'
import {
  hypertunePlugin,
  hypertuneKey,
} from '~/generated/hypertune.vue'

const hypertuneSource = createSourceForServerOnly({
  token: process.env.HYPERTUNE_TOKEN!,
  shouldRefreshInitData: false,
})

export default defineNuxtPlugin(async (nuxtApp) => {
  let serverData: {
    dehydratedState: DehydratedState | null
    rootArgs: RootArgs
  }

  if (import.meta.server) {
    await hypertuneSource.initIfNeeded() // Check for flag updates

    const rootArgs = computed<RootArgs>(() => {
      return {
        context: {
          environment: 'development',
          user: {
            id: 'e23cc9a8-0287-40aa-8500-6802df91e56a',
            name: 'Example User',
            email: '[email protected]',
          },
        },
      }
    })

    const hypertune = computed(() =>
      hypertuneSource.root({ args: rootArgs.value })
    )
    nuxtApp.vueApp.provide(hypertuneKey, hypertune)

    serverData = {
      dehydratedState: hypertune.value.dehydrate(),
      rootArgs: hypertune.value.getRootArgs(),
    }
  }

  useHydration(
    'hypertune',
    () => serverData,
    ({ dehydratedState, rootArgs }) => {
      const runtimeConfig = useRuntimeConfig()
      nuxtApp.vueApp.use(hypertunePlugin, {
        createSourceOptions: {
          token: runtimeConfig.public.hypertuneToken,
        },
        dehydratedState,
        rootArgs,
      })
    }
  )
})

Then use the generated useHypertune composable to access your flags:

components/Example.vue

<script setup lang="ts">
import { useHypertune } from "~/generated/hypertune.vue";

const hypertune = useHypertune();
</script>

<template>
  <div>
    Example Flag:
    {{ hypertune.exampleFlag({ fallback: false }) }}
  </div>
</template>

If you have a Content Security Policy, add the following to your connect-src directive: https://edge.hypertune.com https://gcp.fasthorse.workers.dev. This enables reporting of flag evaluations, experiment exposures, and analytics events.

5. (Optional) Include a build-time snapshot

If you try accessing a flag immediately after the app loads, you'll get your hardcoded fallback value if the SDK hasn't initialized from Hypertune Edge yet. This can result in layout shift or a flicker if the flag value changes when the SDK initializes.

To avoid this, you can include a snapshot of your flag logic in the generated client at build time. The SDK will instantly initialize from the snapshot first before fetching the latest flag logic from Hypertune Edge.

Add the following environment variable to your .env file:

HYPERTUNE_INCLUDE_INIT_DATA=true

Then regenerate the client.

You can keep the snapshot fresh by setting up a webhook to regenerate the client and redeploy your app on every Hypertune commit. In this case, you don't need to initialize from Hypertune Edge at all.

Next steps

Now you can update the logic for exampleFlag from the Hypertune UI without updating your code or waiting for a new build, deployment, or app release.

To add a new flag, create it in the Hypertune UI then regenerate the client.