# Pendulum

> Pendulum is a Shopify app that combines branded invoice PDFs with an automated, multi-touch payment-reminder cadence. It is built for Shopify merchants whose business runs on quotes, draft orders, and custom production, where the order is the start of the job rather than the end.

## What Pendulum does

- Generates branded invoice PDFs that match the merchant's store, not Shopify's default template. Light and dark themes, per-element color control, logo and watermark variants, and a banking/terms link.
- Runs a real multi-touch payment-reminder sequence (for example Day +3, +7, +14) that escalates in tone across Friendly, Firm, and Urgent presets. Reminders are branded, signed, and reply to the merchant's real inbox.
- Redesigns Shopify's order-confirmation and draft-invoice emails so every customer email is branded and carries a PDF download button.
- Lets the merchant print or download a branded invoice for any order directly from the Shopify order detail Print menu, with full Bill To, Ship To, and company details.

## What Pendulum is not

- Not a payment processor. It does not replace Shopify Payments or Stripe. Reminder emails deep-link to the existing Shopify checkout or invoice URL, and customers pay with whatever method is already on the store.
- Not an accounting system. It does not replace QuickBooks. Invoice totals reflect exactly what Shopify recorded for the order.
- Shopify only. No other sales channels in v1. Built for US-based merchants; EU-specific e-invoicing (PEPPOL, VAT-MOSS) is not supported in v1.

## Who it is for

Custom apparel and merch shops, screen printers and embroiderers, signage and engravers, custom jewelers, wholesale food and catering, and B2B manufacturers. Any Shopify merchant whose fulfillment runs longer than a checkout: quote, proof, production, ship, invoice.

## Pricing

Billed through the Shopify Billing API and appearing on the merchant's monthly Shopify invoice. Every plan includes a 14-day free trial with no credit card required.

- Starter: 15 USD per month. Up to 100 invoices per month, branded PDFs, fixed 3-touch reminder cadence.
- Growth: 29 USD per month. Up to 500 invoices per month, editable cadence and templates, send tracking, all preset themes, Pendulum branding removed.
- Pro: 49 USD per month. Unlimited invoices, verified sender from the merchant's own domain, per-customer template overrides, and HMAC-signed outbound webhooks.

Annual billing is two months free on every plan.

## Who built it

Pendulum is built by Alchemy Merch, a custom merch shop that has run on Shopify since 2020 and uses Pendulum to run its own business.

## Links

- Home: https://penduluminvoices.com
- Shopify invoice app overview (draft orders, B2B, custom production): https://penduluminvoices.com/shopify-invoice-app
- Install on Shopify: https://penduluminvoices.com/install
- Help center: https://penduluminvoices.com/help
- Webhooks reference: https://penduluminvoices.com/docs/webhooks
- Support: https://penduluminvoices.com/support
- Privacy: https://penduluminvoices.com/legal/privacy
- Terms: https://penduluminvoices.com/legal/terms