How to Custom Build an eCommerce Feature (Without Wasting Time or Budget)

When you need to build a custom feature for your eCommerce site, the stakes are high.

Do it right—and you can unlock new revenue streams, improve UX, or streamline operations.

Do it wrong—and you’ll spend weeks (or months) on something no one uses or understands.

In this guide, we’ll walk through a 4-step process to make sure your custom feature actually delivers.

This approach helps you:

• Avoid overbuilding
• Stay within budget
• Keep internal teams aligned
• Deliver real ROI

🎥 Prefer to watch the video? Check it out here (7:34)

The 4-Step Process for Building eCommerce Features That Work

Step 1: Define the Real Goal (Not the Feature)

Before writing a single requirement or talking to a dev, zoom out.

What business problem are you solving?

Who benefits—and how?

Example:

Let’s say you want an “Out of Stock Notification” feature. The goal isn’t the notification—it’s to recover lost sales and improve customer satisfaction when inventory returns.

By stating the goal clearly, you can:

• Explore simpler solutions (like native tools or apps)
• Keep your dev team focused
• Avoid unnecessary scope creep

🎯 Pro Tip: Start with the outcome, not the idea.

Step 2: Refine Requirements With Real Data

Once you’ve proven the feature is necessary (see Build vs. Buy guide), the next step is refining what’s actually needed.

Use real-world feedback:

• How are users interacting with existing solutions?
• What’s missing from prebuilt options?
• What’s being ignored or misunderstood?

Then rank your requirements:

• Non-negotiables (must be in Phase 1)
• Nice-to-haves (future phase candidates)
• Out-of-scope (don’t waste time here)

You’ll want to avoid rebuilding cool-but-irrelevant app features. Every single item should justify its place with measurable value.

Step 3: Translate Into Actionable Development Work

Once your requirements are solid, convert them into dev tickets.

Each ticket should include:

• A clear task title
• Acceptance criteria (how do we know it’s done right?)
• Technical context (how it might be built)

Keep tickets small—ideally under 8 hours of work—so progress can be tracked and feedback cycles are tight.

🛠 Work with your development partner to define tickets collaboratively. This step ensures nothing is misunderstood or mis-scoped.

Step 4: Don’t Skip Change Management

Your work’s not done at launch.

Internal teams need to know what changed—and why. So do your customers.

Communicate clearly:

• Bullet points for sales, support, and leadership
• Screenshots and blurbs for marketing
• Simple release notes or internal docs

Why does this matter? Because internal adoption and customer usage are what actually drive ROI.

📢 A new feature is a marketing opportunity—treat it like one.

Use Case: Back-in-Stock Notifications (Done Right)

Say you want to send back-in-stock texts to loyalty members first. Here’s how this would play out:

• Goal: Prioritize loyal customers, recover sales, improve brand affinity
• Proof of Concept: Use an app or manual process to test if customers respond
• Refined Requirements: Text priority, store-by-store customization, loyalty list integration
• Phased Rollout: Launch text alerts first; expand to geolocation-based messaging later

This structure ensures you only build what moves the needle.

Frequently Asked Questions