How Masterfile comics work

Masterfile is a Shopify app for comic book retailers. It pulls a normalized comic catalog from your distributors (PRH and Lunar), creates Shopify products from it, and runs the recurring work that comes with selling weekly comics — pre-orders, subscriptions, and the order you submit back to each distributor every week.

This page is the map: how the pieces fit together, and what's automatic versus what you do.

The pipeline

Data flows in one direction:

Distributor catalog → Masterfile → Your Shopify store

1. Distributors publish a weekly catalog of titles, covers, credits, prices, FOC and on-sale dates.
2. Masterfile ingests, normalizes, and stores all of it in a single comic database — the Masterfile catalog.
3. Your sync rules decide which slice of that catalog flows into your Shopify store as products.

The pipeline runs continuously. New issues that match your rules are created automatically; upstream changes to existing issues (covers, dates, pricing) are pushed to the matching Shopify product without you doing anything.

How Masterfile maps to Shopify

The most important thing to know up front is that Masterfile speaks comic-shop nouns and Shopify speaks commerce nouns — and the app maps between them. The mapping is one-to-one and predictable.

So a comic issue with five covers becomes one Shopify product with five variants. The Subscribe option that appears next to "One-time purchase" on an ongoing series is a Shopify selling plan that Masterfile attaches automatically. A pre-order on issue #5's primary cover is, mechanically, Shopify allowing the variant to oversell — and Masterfile reads the resulting negative inventory as your committed customer demand.

Internalize this mapping and the rest of the app clicks into place: when sync writes data, it writes Shopify product and variant fields; when a customer pre-orders, it lands on a variant's inventory; when subscriptions bill, they bill a Shopify selling plan.

The four workflows

Everything Masterfile does is one of these four flows.

1. Product sync

Sync rules decide which issues become products. Once an issue matches, product sync creates and maintains the Shopify product end-to-end: titles, descriptions, images, prices, COMET metafields, and the variant inventory policies that make pre-orders work. Manual edits you make in Shopify (titles, descriptions, prices) and overrides you make through the COMET admin blocks are preserved through every future sync.

Configure once: Configure sync rules.

2. Pre-orders

Every comic Masterfile syncs is created tracked, with zero inventory, and "Continue selling when out of stock" — i.e. Shopify is told to accept orders past zero. Customers pre-ordering a future issue push the variant's available count negative, and that's the signal Masterfile reads as committed demand.

Pre-orders handle the lifecycle automatically: badge on the storefront, expected-date messaging in cart and checkout, locking the variant at FOC so no new orders land after cutoff, and archiving empty products 30 days after release.

3. Subscriptions

A subscription is one customer signed up to one ongoing series — Absolute Batman, Saga, Ultimate Spider-Man. Each new issue that releases bills the customer automatically and rolls a copy onto your next distributor order, the same way a shopper-placed pre-order would. Subscriptions are off by default; flip one toggle in sync rules to enable them.

4. Distributor orders

Distributor orders are the rollup. Every customer commitment — pre-orders and subscription billings — is grouped by distributor and FOC date into a draft restock order. Before each FOC, you review the draft, add buffer copies, export the lines to PRH or Lunar, and mark it submitted.

Masterfile keeps the draft in sync with demand right up until you submit. It does not transmit the order to the distributor — that step is yours, by CSV upload (Lunar) or paste (PRH). See Submit a distributor order.

Where Masterfile shows up in Shopify

Masterfile lives in five surfaces inside Shopify:

• Masterfile in Shopify admin (Shopify admin → Apps → Masterfile) — home of Sync Rules, Cost Discounts, the Issues catalog, the Series list, Subscriptions, Distributor Ops (orders and shipments), and the Storefront Catalog settings. Sections only appear in the sidebar if your plan unlocks them.
• Three storefront theme blocks on the product page — Comic Details, Pre-Order Notice, and Subscription Picker. Set up via Configure your Shopify product theme.
• Two admin blocks on every product and variant page — COMET Product Fields and COMET Variant Fields. Set up via Pin the Masterfile admin blocks.
• Customer-account blocks — My Subscriptions, My Collection, and a Digital Editions library (on Retailer Ops plans). Set up via Enable Shopify customer account pages.
• A hosted catalog page, served by Masterfile through Shopify's app proxy, for searching and filtering your full active catalog. Set up via Set up your catalog page.

Adding the storefront, admin, and customer-account blocks is part of Getting Started. Each is a one-time setup.

Comic data: the COMET standard

Every comic-specific field Masterfile syncs — series name, issue number, age rating, writers, artists, FOC date, on-sale date, item ID — is written as a Shopify metafield in the COMET namespace. COMET is ComicsPRO's open metadata standard for the comic industry. Using it means your data is portable, and it means the storefront catalog filters, the Comic Details theme block, and the COMET admin blocks all read from the same source.

When the distributor's data is wrong on a single product, edit the field through the COMET admin block. The override is preserved through every future sync, and Masterfile is automatically notified so the upstream catalog can be fixed for everyone.

What's automatic vs. what you do

Automatic, every day:

• Pulling fresh distributor catalogs and updating any synced product whose upstream data changed.
• Creating Shopify products for new issues that match your sync rules.
• Locking variants at FOC, archiving empty products 30 days after on-sale, and deleting them after another 30 days if they stay empty.
• Billing subscriptions when each new issue releases and rolling those copies onto the right distributor order.
• Updating distributor order drafts as new pre-orders and subscription billings land.

You, in roughly this order:

1. Choose a plan.
2. Configure sync rules — distributors, publishers, formats, age ratings you carry, and whether subscriptions are enabled.
3. Set distributor costs so margin reports work.
4. Set up the catalog page, theme blocks, customer-account pages, and admin blocks.
5. Every week, before each FOC, review the draft distributor order, add buffer copies, export to the distributor, and mark it submitted.

Everything else is troubleshooting — an issue didn't sync, the picker isn't showing, a customer's account looks empty. Those have dedicated guides.