From PostHog

import posthog from 'posthog-js';posthog.init('phc_YOUR_KEY', {  api_host: 'https://app.posthog.com',});

import { AvsbClient } from '@avsbhq/browser';const client = new AvsbClient({  sdkKey: 'sdk_production_xxxxxxxxxxxxxxxx',  context: { kind: 'user', key: posthog.get_distinct_id() },});await client.onReady();

import { PostHog } from 'posthog-node';const posthog = new PostHog('phc_YOUR_KEY', { host: 'https://app.posthog.com' });

import { AvsbServer } from '@avsbhq/node';const server = new AvsbServer({ sdkKey: process.env.AVSB_SDK_KEY! });const result = await server.onReady();

// Identify after loginposthog.identify('user_123', {  email: 'user@example.com',  plan: 'pro',  company: 'Acme',});// Partial update: re-call identify with all properties

// Full context replacement (equivalent to PostHog identify)client.identify({  kind: 'user',  key: 'user_123',  email: 'user@example.com',  plan: 'pro',  company: 'Acme',});// Partial attribute patch: no need to repeat unchanged fieldsclient.updateAttributes({ plan: 'enterprise' });// Stitch anonymous pre-login identity to the identified user. Synchronous:// it records the moment, it does not move past decisions.client.alias(  { kind: 'user', key: posthog.get_distinct_id() },  // anonymous id  { kind: 'user', key: 'user_123' }                   // identified id);

// Boolean checkconst showBanner = posthog.isFeatureEnabled('show_banner');// Multivariate / string variantconst theme = posthog.getFeatureFlag('homepage_theme'); // returns string | boolean | undefined// JSON payloadconst config = posthog.getFeatureFlagPayload('pricing_config'); // returns JsonType | null

// Boolean flagconst showBanner = client.getBoolFlag('show_banner', false).value;// Or use isEnabled(): true only when a real decision was made (a rule,// holdout, bandit, or override matched, not just the default) and the// value is truthy.const enabled = client.getBoolFlag('show_banner', false).isEnabled();// String / multivariate flagconst theme = client.getStringFlag('homepage_theme', 'default').value;// JSON payload. Unlike PostHog's `JsonType | null`, the default you pass is// the type you get back, so there is no null branch at the call site.interface PricingConfig { basePrice: number; currency: string }const config = client.getJsonFlag<PricingConfig>('pricing_config', {  basePrice: 99,  currency: 'USD',}).value;// Full envelope (equivalent to fetching metadata)const flag = client.getBoolFlag('show_banner', false);flag.variationKey   // 'test' | 'control' | nullflag.source         // 'rule' | 'default' | 'holdout' | ...flag.reasons        // string[]

// Requires a distinct ID per call (no client-level binding)const flagValue = await posthog.getFeatureFlag('show_banner', 'user_123');const isEnabled = await posthog.isFeatureEnabled('show_banner', 'user_123');

const flag = server.forUser({ kind: 'user', key: 'user_123' })  .getBoolFlag('show_banner', false);

posthog.capture('purchase_completed', {  revenue: 49.99,  orderId: 'ord_99',  plan: 'pro',});

// Sends to A vs B experiment analytics only. `revenue` is money in major// units (49.99, not 4999). Conversion events do not store properties// (only exposure events do), so orderId and plan have no A vs B// equivalent on this call.client.track('purchase_completed', { revenue: 49.99 });// If keeping PostHog for analytics, also call:// posthog.capture('purchase_completed', { revenue: 49.99, ... });

import type { MultiContext } from '@avsbhq/core';const ctx: MultiContext = {  kind: 'multi',  user:         { kind: 'user',         key: 'user_123', plan: 'pro' },  organization: { kind: 'organization', key: 'org_42',   tier: 'enterprise' },};server.forUser(ctx).getBoolFlag('enterprise_feature', false);

posthog.onFeatureFlags((flags: string[]) => {  // Flags loaded or reloaded});

client.on('configUpdate', ({ reason }) => {  // Datafile refreshed; reason: 'poll' | 'stream' | 'manual'});client.on('flagChange', ({ flagKey, previousValue, newValue }) => {  // A specific flag value changed});// Manual refresh (equivalent to reloadFeatureFlags)await client.refresh();

// Server componentconst flagValue = await posthog.isFeatureEnabled('show_banner', 'user_123');

// Server component (app/layout.tsx)import { AvsbProvider } from '@avsbhq/react';import { fetchDatafile } from '@avsbhq/browser/server';const datafile = await fetchDatafile(process.env.AVSB_SDK_KEY!);// Client provider: flags evaluate synchronously on first render<AvsbProvider sdkKey="..." context={ctx} bootstrap={datafile ?? undefined}>  <YourApp /></AvsbProvider>

await posthog.shutdown();

await server.close(); // flushes buffered events, stops polling

// PostHog test mode: use overrideFeatureFlagposthog.featureFlags.override({ show_banner: true });

import { createMockClient } from '@avsbhq/test';const mock = createMockClient({  flags: {    show_banner: true,    homepage_theme: 'blue',  },});