10 Essential Shopify App Development Best Practices for 2025

Introduction

Shopify app development has evolved rapidly, with GraphQL-first APIs, Shopify Functions, Hydrogen on React Router 7, and an ever-more opinionated Liquid layer for themes. In 2025, success means balancing performance, secure architecture, and a merchant-first UX while adhering to the latest platform policies and Liquid guidelines.

1) Performance Optimization

Performance is a key driver of adoption and retention. Focus on lean payloads, fewer round trips, and smart caching at the edge.

• Prefer GraphQL (with bulk operations when appropriate) to limit over-fetching.
• Cache Admin and Storefront responses thoughtfully (ETags, stale-while-revalidate), and add edge caching on CDN/Workers.
• Ship small JS bundles in embedded apps; defer non-critical code.
• Use Liquid’s native image helpers and default lazy loading behavior for non-LCP media.

Liquid example: LCP-friendly hero image + lazy-loaded gallery

{% comment %}
For the top (LCP) image, explicitly set fetchpriority="high".
Below-the-fold images default to lazy load; you can also control via section.index/section.location.
{% endcomment %}

<div class="hero">
  {{ product.featured_image | image_url: width: 1600 | image_tag:
      loading: "eager",
      fetchpriority: "high",
      widths: "800, 1200, 1600",
      sizes: "(min-width: 768px) 80vw, 100vw",
      alt: product.title }}
</div>

<div class="gallery">
  {% for image in product.images %}
    {{ image | image_url: width: 800 | image_tag:
        loading: section.index > 0 ? "lazy" : "auto",
        alt: product.title | append: " image " | append: forloop.index }}
  {% endfor %}
</div>

Liquid’s image_tag and section metadata (for example, section.index, section.location) help control loading priority and improve CLS/LCP.

2) Security Best Practices

• Use OAuth with least-privilege scopes; store tokens securely.
• Verify webhook HMAC signatures and rotate secrets.
• Serve everything over HTTPS; enforce same-site cookies in embedded contexts.

Node (Express) example: Webhook verification

import crypto from "node:crypto";
import express from "express";

const app = express();
app.post("/webhooks/orders/create", express.raw({ type: "application/json" }), (req, res) => {
  const secret = process.env.SHOPIFY_WEBHOOK_SECRET;
  const hmac = req.get("X-Shopify-Hmac-Sha256");
  const digest = crypto.createHmac("sha256", secret).update(req.body).digest("base64");

  if (!crypto.timingSafeEqual(Buffer.from(hmac || "", "utf8"), Buffer.from(digest, "utf8"))) {
    return res.status(401).send("Invalid signature");
  }

  // Process webhook...
  res.status(200).send("OK");
});

3) User Experience Design

Use Shopify’s Polaris components for admin/embedded apps, keep flows focused, and provide helpful, inline guidance. In 2025, Polaris offers a unified, standardized UI system to build across surfaces.

4) API-First Development

• Favor GraphQL Admin/Storefront APIs for efficiency.
• Use webhooks for event-driven updates (orders, products, customers).
• For large exports, use GraphQL bulk operations.

GraphQL bulk example (Admin API)

mutation startBulk {
  bulkOperationRunQuery(
    query: """
      {
        products {
          edges {
            node {
              id
              title
              variants { edges { node { id sku price } } }
            }
          }
        }
      }
    """
  ) { bulkOperation { id status } userErrors { field message } }
}

5) Shopify Functions & Extensibility

Replace legacy Scripts with Functions for discounts, shipping, and payments. Shopify has extended Scripts’ final sunset to June 30, 2026, but new work should target Functions.

Functions (JavaScript) example: Threshold-based item discount

// shopify.function.ts (Discounts - Cart Line)
// Minimal illustrative example using the Functions JS runtime.
import { run } from "shopify-function";

export default run((input) => {
  const MIN_QTY = 3;
  const PCT = 0.10;

  const lines = input.cart.lines.map((line) => {
    const qty = line.quantity;
    if (qty >= MIN_QTY) {
      return {
        target: { cartLine: { id: line.id } },
        value: { percentage: { value: (PCT * 100).toString() } },
        message: `Saved ${(PCT*100)}% for buying ${MIN_QTY}+`,
      };
    }
    return null;
  }).filter(Boolean);

  return { discounts: lines, discountApplicationStrategy: "MAXIMUM" };
});

6) Scalable Architecture

• Prefer serverless/edge (Workers, Vercel, Lambda) for bursty workloads.
• Use queues for webhooks and long-running tasks.
• Respect Shopify API rate limits; back off and retry on 429.

Rate-limit aware fetch

async function shopifyFetch(url, opts = {}) {
  for (let attempt = 0; attempt < 5; attempt++) {
    const res = await fetch(url, opts);
    if (res.status !== 429) return res;
    const retryAfter = Number(res.headers.get("Retry-After") || 2);
    await new Promise(r => setTimeout(r, (retryAfter + attempt) * 1000));
  }
  throw new Error("Rate limit exceeded after retries");
}

7) Data Privacy & Compliance

• Honor GDPR/CCPA/DPDP requests via Shopify’s data protection endpoints and webhooks.
• Encrypt data at rest and in transit; define retention windows.

Erasure webhook handler (pseudo-Node)

app.post("/gdpr/customers/redact", verifyShopifyWebhook, async (req, res) => {
  const { customer } = JSON.parse(req.body.toString());
  await redactCustomerDataFromAppDB(customer.id);
  res.sendStatus(200);
});

8) Testing & QA Automation

• Unit/integration tests (Vitest/Jest) + E2E (Playwright/Cypress).
• Mock Shopify APIs for fast/isolated tests.
• Use Shopify CLI for local dev, previews, and tunneling.

Playwright snippet: Embedded app smoke test

import { test, expect } from "@playwright/test";
test("loads embedded app home", async ({ page }) => {
  await page.goto("https://your-app.test/auth/callback?shop=test-shop.myshopify.com");
  await expect(page.getByRole("heading", { name: "Dashboard" })).toBeVisible();
});

9) Observability & Monitoring

• Structured logs (JSON) with request IDs and shop domain.
• Metrics (p95 latency, error rates, queue depth) and alerts.
• Trace webhook pipelines end-to-end.

Structured log example

console.log(JSON.stringify({
  level: "info",
  msg: "productsSync.completed",
  shop: shopDomain,
  duration_ms: Date.now() - start,
  items: count
}));

10) Merchant-Centric Onboarding & Support

• Guided setup with sensible defaults and staged permissions.
• Inline docs/tooltips; fail-soft with clear error recovery.
• Usage analytics to find friction and iterate quickly.

Liquid: 2025-Ready Patterns You Should Use

Modern Liquid encourages isolation, explicitness, and performance.

{% comment %} Pass variables explicitly; snippet scope is isolated {% endcomment %}
{% render 'product-card', product: product, show_badge: true %}

{% comment %} In Liquid templates you can select a layout via the tag {% endcomment %}
{% layout 'theme' %}
<main>...</main>

Checkout & Scripts: Deadlines You Must Track

• Checkout.liquid & script-tag customizations: Info/Shipping/Payment page upgrade deadline was Aug 13, 2024; Thank you/Order status pages deadline is Aug 28, 2025. Plan migrations to Checkout Extensibility.
• Shopify Scripts: Full deprecation extended to June 30, 2026. Prioritize migrating to Functions now.

Conclusion

In 2025, high-quality Shopify apps are fast, secure, observable, and built on modern primitives: GraphQL, Functions, Polaris, and Liquid’s current best practices (notably, render and improved asset helpers). Adopt the patterns and code above to ship apps that delight merchants and scale with Shopify’s rapidly evolving platform.