Configuration

Experiment projects have two configuration files with distinct responsibilities.

experiment.config.js

This file sits at the project root and configures the build and live-preview tools.

export default {
    targetUrl: 'https://www.samsung.com/uk/smartphones/all-smartphones/',
    runtime: {
        globalObject: 'sgd',
        includeEmergencyBrake: true,
    },
    live: {
        variation: 0,
        overlay: 'visible',
        profile: 'ephemeral',
    },
};

Field	Type	Description
targetUrl	string	Page opened by pnpm live. The scaffold derives it from E2E market answers when available.
runtime.globalObject	string	The IIFE window namespace. The bundle registers as window[globalObject]. Change the scaffolded value only if it conflicts with another experiment.
runtime.includeEmergencyBrake	boolean	Enables the runtime emergency-brake check in runScript().
live.variation	number | string	Variation used by pnpm live. Accepts a zero-based index or discovered folder name such as v2 or control.
live.overlay	'visible' | 'hidden'	Shows or hides the live-injection status overlay.
live.profile	'ephemeral' | 'shared'	Uses a temporary browser profile or a persistent OS-cache profile.

src/config.js

Keep experiment-specific selectors and copy here. This is usually the first file you edit.

export const selectors = {
    primary: '.some-page-element',
    fallbacks: ['.alternate-selector', 'body'],
};

export const buttonText = 'Click Me';

Export	Type	Description
selectors.primary	string	CSS selector for the DOM element the experiment injects adjacent to. Must be unique and stable on the target page.
selectors.fallbacks	string[]	Fallback selectors used by mountExperiment if selectors.primary yields no match. Keep them ordered from most specific to broadest.
buttonText	string	Scaffolded button copy.

Finding the right primary selector

Inspect the page in DevTools and choose a stable, unique class or attribute near the injection point. Avoid session-specific IDs, generated class names, and long nth-child chains.

Add locale, translations, model codes, or API-specific values only when the experiment needs them.