Skip the Specs, Show the Demo: A New Approach to Product Development in the AI Era

In the AI era, there's more than one way to build: a faster way to align and validate ideas

Why is this worth reading?
If you've ever been stuck in endless spec reviews, unclear requirements, or communication loops, this article may offer a fresh alternative. I share how I built a fully working DocuSign integration in a week using AI, and introduce a prototype-first approach I call Demo-Driven Development. For early-stage teams or resource-constrained builders, this may be a more effective way to move forward than traditional spec-heavy workflows. Whether you're a PM, engineer, or someone launching something new, you'll find ideas you can act on.

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The limits of traditional processes

In traditional product teams, PMs define the requirements, designers produce wireframes, and engineers implement them. This separation of duties makes sense in large organizations—it ensures stability and accountability. But it also creates significant communication overhead.

Worse, there's often a gap between what users "understand" and what they "actually use."

• For B2B products, we show mockups and ask, "Would you use this like that?"
• For B2C, we rely on surveys or click-throughs to simulate intent—but real behavior is hard to imagine without something to try.

Even with agile methods like Scrum, where we release something every two weeks, the cost of iteration is still high.

A new option: Build a prototype in one week with AI

What if we had another option?

Use a 1–2 person micro team—say, a PM and a technical partner, or a PM who can build—to skip full specs and directly deliver a working prototype.

This is not about skipping alignment. It's about using a prototype as the source of alignment—verifying needs through actual interactions, not documents.

With the help of AI tools—prompt-based coding, GitHub Copilot, or AI agents—you can quickly build a product that is functional, adaptable, and understandable.

Case study: DocuSign automation integration

Recently, I worked on a case where our sales team was managing contracts and forms via email.

As our customer base grew, this became unscalable. There were steps that required manual confirmation (like checking inventory) before the client could even sign. We needed automation.

Using traditional methods, this would’ve taken months:

• I wasn’t familiar with DocuSign’s APIs, templates, and webhook systems.
• We didn’t have a confirmed spec—sales didn’t know exactly what they needed.
• Writing a full spec before building felt risky and pointless.

So instead of stalling, I built a demo.

I did quick alignment via a few simple PPT flowcharts, then used AI-assisted coding to create a working version in a week:

• Used composite templates to allow “fill first, sign later” flows
• Triggered different documents for individuals vs companies
• Embedded the flow into our frontend
• Automatically routed CCs, updated webhook status, and eliminated manual handoffs

Now sales can demo this directly to clients. Clients interact with the real forms. Feedback is grounded in reality, not assumptions. This revived a project that had been stalled for half a year.

I call this method Demo-Driven Development.

It's not a silver bullet—but it gives you direction

Is this approach perfect? No.

AI-generated code can be buggy, inconsistent, or break existing features. Eventually, you’ll need professional engineers to harden the system. But in early stages—when you don’t even know if the market wants what you're building—this method reduces risk.

Worst case? You waste a week. No spec writing, no stakeholder meetings, no months of negotiation.

A Flavor of Lean MVP—with a Twist

This is, fundamentally, a lean MVP approach: build the minimum version to test your assumption.

The difference is emphasis: Demo-Driven Development starts with a working demo to align understanding, rather than with planning sessions or spec documents.

It's not about building fast for its own sake—it's about making feedback loops more real, more specific, and more grounded in actual user interaction.

A lightweight, action-first mindset

This isn't about glorifying overwork or turning PMs into engineers.

It's about using new tools to reduce the cost of trying. To validate ideas before overcommitting.

So if you’re a builder—or supporting an early product with few resources—I recommend asking:

“Can I build something testable before asking for alignment?”

Because products aren't born from consensus. They're born from momentum.