shopify-developer

---
name: shopify-developer
description: Comprehensive Shopify development skill for theme architecture, Liquid, Admin API, Storefront API, metafields/metaobjects, checkout extensibility, Shopify Functions, webhooks, and platform limits. Use when implementing or debugging Shopify app/theme work, API integrations, checkout customizations, or data modeling. For Hydrogen/headless framework specifics, use Context7 MCP for current framework docs.
---

# Shopify Developer

Use this skill as the coordination hub. Keep implementation details in `references/` files and load only the file(s) needed for the task.

## Authentication

Use quarterly API versions in all endpoints, for example `2026-01`.

Admin GraphQL endpoint:

```bash
https://${SHOP}.myshopify.com/admin/api/${API_VERSION}/graphql.json
```

Admin API headers:

```bash
X-Shopify-Access-Token: ${SHOPIFY_ACCESS_TOKEN}
Content-Type: application/json
```

Storefront GraphQL endpoint:

```bash
https://${SHOP}.myshopify.com/api/${API_VERSION}/graphql.json
```

Storefront API headers:

```bash
X-Shopify-Storefront-Access-Token: ${SHOPIFY_STOREFRONT_TOKEN}
Content-Type: application/json
```

Source environment variables from `~/.agents/.env` before running commands.

## API Conventions

- Prefer GraphQL over REST for new work.
- Include API version in the URL; update quarterly.
- Paginate with cursors (`first/after`) rather than page numbers.
- Handle both top-level `errors` and mutation `userErrors`.
- Budget GraphQL query cost and throttle based on available points.
- Use bulk operations for large export/import workloads.
- Prefer idempotent mutation patterns for retry-safe writes.

## Core Workflows

Theme development pipeline:
- Pull current theme state, iterate in local dev, push to draft first.
- Validate theme editor behavior (sections, blocks, settings) before live publish.
- Reference: `references/theme-architecture.md`, `references/liquid.md`.

Product and metafield management:
- Define metafield/metaobject schemas first, then write values through Admin API.
- Access values in Liquid and Storefront API using type-safe patterns.
- Reference: `references/admin-api.md`, `references/metafields-metaobjects.md`.

Checkout customization:
- Use Checkout UI Extensions and Shopify Functions; avoid legacy checkout patterns.
- Separate UI concerns (extensions) from pricing/fulfillment logic (functions).
- Reference: `references/checkout-extensibility.md`, `references/shopify-functions.md`.

## Reference Files

| File | When to read |
|---|---|
| `references/admin-api.md` | Product/order/customer/inventory GraphQL workflows; bulk operations. Grep hint: `bulkOperation`. |
| `references/storefront-api.md` | Headless storefront queries, cart operations, customer account flows, localization. Grep hint: `cart`. |
| `references/metafields-metaobjects.md` | Metafield types, definitions, Liquid access, metaobject CRUD. Grep hint: `metafieldsSet`. |
| `references/liquid.md` | Liquid objects, filters, tags, render patterns, metafield rendering, performance tuning. |
| `references/theme-architecture.md` | OS 2.0 structure, section schema, templates, app blocks, CLI deployment flow. |
| `references/checkout-extensibility.md` | Checkout UI extensions, web pixels, migration timelines, post-purchase extensions. |
| `references/shopify-functions.md` | Function types, WASM constraints, implementation/testing, Scripts migration path. |
| `references/webhooks-events.md` | Webhook topics, compliance webhooks, HMAC verification, retries/idempotency. |
| `references/platform-limits.md` | API versioning, limits, deprecation timelines, plan-specific capabilities. |

## Gotchas

1. Use `.value` when rendering metafields in Liquid.
2. Use `metafieldsDelete` (plural), not singular deletion mutation names.
3. Do not rely on `checkout.liquid`; migrate to checkout extensibility.
4. Plan Scripts migration before June 30, 2026 sunset.
5. Treat REST Admin API as maintenance-only for new implementation.
6. Rotate to supported API versions before the 12-month support window ends.
7. Implement idempotency keys for retry-safe writes before April 1, 2026 enforcement.
8. Remove deprecated Storefront tax fields during API upgrades.
9. Do not hand-edit `config/settings_data.json`; use Theme Editor.
10. Keep Shopify Functions logic minimal to stay inside strict runtime limits.