README

Back-in-stock notifications that scale. Customers subscribe to out-of-stock products and get notified when inventory returns — but unlike most "notify me" extensions, Stock Radar is built for stores that move real volume.

Ships Luma support out of the box and a full GraphQL surface for headless storefronts. Hyvä support lives in the companion module byte8/module-stock-radar-hyva.

Why another back-in-stock module

Most free competitors blast all subscribers in one go and forget about the merchandiser. Stock Radar fixes both ends:

• Throttled batched notifications — when 800 people subscribed to a sold-out hero SKU, dispatch is staggered over a configurable window (default 30 min) so a single restock event doesn't crash inventory or your mail provider.
• Per-variant subscriptions on configurables — subscribe to "Red, M" specifically, not just the parent.
• Demand heatmap in admin — sortable grid of products with the most pending subscriptions, so reorder decisions are data-driven.
• GraphQL surface — Hyvä, headless, and PWA Studio out of the box (REST adapter not shipped — file an issue if you need it).
• GDPR-first — guest subscribers stored with hashed email + unsubscribe token; data subject deletion lookups are O(1) by email_hash.
• Admin alert on high-demand SKUs — when pending subscriber count for a single product first crosses a configurable threshold, a message appears in the Magento admin notification inbox (bell icon top-right).

Features

Subscription

• "Notify me" button on out-of-stock product pages (Luma block + GraphQL mutation byte8StockRadarSubscribe; Hyvä via companion module)
• Customer + guest support
• Per-variant subscriptions for configurable products
• One-click unsubscribe via signed token
• Per-store email/storefront templates

Dispatch

• Stock observer queues subscriptions into byte8_stock_radar_dispatch when is_in_stock flips from 0 to 1
• Cron worker drains the queue with a configurable throttle window
• Failed sends retried with exponential backoff (max 3 attempts)
• Skips subscriptions older than the configurable expiry (default 90 days)

Admin

• Subscription grid (Byte8 → Stock Radar → Subscriptions)
• Demand heatmap (Byte8 → Stock Radar → Demand) — products ranked by pending subscriber count
• Per-store config (Stores → Configuration → Byte8 → Stock Radar):
  • enable/disable
  • throttle window (minutes)
  • subscription expiry (days)
  • email sender / template
  • admin-alert threshold (post a message in the admin notification inbox when subscriber count for a single SKU first crosses N — see docs/advanced/admin-alerts.md)
  • five admin-toggleable abuse-protection switches (rate limit, honeypot, hide-created-flag, CAPTCHA, double opt-in) — see docs/configuration/general.md

GraphQL

mutation { byte8StockRadarSubscribe(input: { sku: "ABC-123", email: "x@y.com" }) { success message } }
mutation { byte8StockRadarUnsubscribe(token: "...") { success } }
query   { byte8StockRadarSubscriptions { items { sku created_at status } } }

Database

Two tables:

• byte8_stock_radar_subscription — one row per (product, email, store)
• byte8_stock_radar_dispatch — staggered send queue, drained by cron

See etc/db_schema.xml for the full schema.

Optional companion modules

• byte8/module-stock-radar-hyva — Hyvä storefront integration.
• byte8/module-stock-radar-plenty — bridges Stock Radar with the Byte8 PlentyONE connector so notifications fire on ERP-confirmed inbound stock, not just Magento stock saves.

Installation

composer require byte8/module-stock-radar
bin/magento module:enable Byte8_StockRadar
bin/magento setup:upgrade
bin/magento setup:di:compile

Cron

The dispatch worker runs every minute by default (byte8_stock_radar_dispatch). Make sure Magento's default cron group is active.

Support

Byte8 Ltd — support@byte8.io