I Tried Building a Full-Stack App with Replit Agent. Here's How It Went 👀

Hanan Nabil — Fri, 23 Oct 2026 08:40:53 +0000

I've been curious about AI coding tools lately, especially the idea of building an entire application just by describing what you want.

So I decided to give Replit Agent a try.

The idea was simple: build something useful, see how much Replit could handle, and find out what happens when things don't go as planned.

That's how QueueLess started.

What I Wanted to Build
QueueLess is a web app for managing appointments and virtual queues.

Think of a clinic where some customers book appointments in advance while others walk in and wait for their turn.

I wanted both experiences in one platform, along with a dashboard where businesses could manage services, employees, and bookings.

Nothing too unusual, but definitely more than a simple CRUD app.

Building It with Replit Agent
I started by describing the idea to Replit Agent and letting it work through the implementation.

It generated a full-stack setup using React, TypeScript, Express, PostgreSQL, and Drizzle ORM, with Clerk for authentication and Socket.IO for real-time features.

What surprised me was how quickly I could move from describing a feature to seeing it in the live Preview.

I could ask for a booking page, inspect the result, report what wasn't working, and continue from there.

That feedback loop was probably my favorite part of the experience.

But of course, things weren't always that smooth. 😅

The Part Where Things Broke

At one point, the booking page looked ready, but opening it showed:

Booking page unavailable

After some debugging, Replit Agent identified the problem: a GET endpoint was validating the request body instead of the query parameters.

That small mistake caused an HTTP 400 error and broke the entire booking experience.

There were also TypeScript errors, an API port conflict, and a database migration issue involving existing constraints.

The booking issues were eventually fixed, and I managed to test a complete appointment flow for a sample business called Beauty Clinic.

A customer could select a service, choose an available time, and successfully create an appointment.

HTTP 201 Created 🎉

The queue features still need additional database integration testing, so I wouldn't call the entire app production-ready yet.

What I Actually Think About Replit Agent
The biggest advantage for me was speed.

I didn't have to spend as much time on initial setup, boilerplate, or connecting different parts of the application.

But I also noticed something important: when an AI agent says a feature is implemented, that doesn't necessarily mean the feature works.

I had to keep checking the Preview, testing actual user flows, reading error reports, and sometimes asking the Agent to focus on fixing one problem instead of adding more features.

That's probably my biggest takeaway from this experiment:

AI makes it easier to write code. It doesn't make testing or engineering decisions disappear.

Would I Use It Again?
Yes, especially for prototyping, experimenting with ideas, and getting a project running quickly.

QueueLess is still evolving, and there are things I want to improve. But trying Replit Agent gave me a much better understanding of both the possibilities and limitations of AI-assisted development.

I'm curious how other developers feel about this.

Have you tried Replit Agent? Did it actually save you time, or did you end up spending that time debugging? 😄

DEV Community: Hanan Nabil

I Tried Building a Full-Stack App with Replit Agent. Here's How It Went 👀