The barrier to entry for building full featured apps shrinks by the day, but larger datasets still don’t work by default. What if your app idea needs to analyze millions to billions of rows on the fly? How can you easily fetch and load that data into your database? Plus, how can you make sure your beefy data processing compute scales back down to zero whenever your app is idle?
Combining MotherDuck and Replit is a simple way to build and deploy with just a few prompts, but still scale up to the size of data your app needs. The key thing is that it is easy. In 3 prompts, I vibe coded a working web app that analyzes 10’s of millions of rows. Oh, and in those same 3 prompts it also created a MotherDuck account from scratch, retrieved and stored all that historical data, and set up live API queries from the app as well. Zero to data app in a couple of minutes!
Check out our prior post in this series all about using Vercel V0 with MotherDuck.
Here is a live view of my app after a few more prompts to fine tune the look and feel! What are the chances you get stuck in the airport on your next flight?
Replit is a tool for building apps with an AI agent. It sounds simple, but apps have many moving parts! Replit smoothly handles both development and deployment, including things like authentication. A key value of Replit is that just about anybody can build an app now with Replit in their toolbox. It also has a Design mode so that you can tweak and customize with the keyboard and mouse for those kinds of changes that are hard to describe in a chat.
By default, Replit uses Postgres, but with another sentence in your prompt it can happily use just about any database! MotherDuck is an analytical database (Postgres is transactional), which means that MotherDuck excels at things like reporting queries that summarize large amounts of data as well as bulk loading. Since MotherDuck has a Postgres compatible API option, Replit’s agent was able to use it very naturally. MotherDuck’s SQL syntax is also 99% Postgres compatible, so the agent could write the SQL on our behalf as well.
Follow this recipe to be building data apps in no time!
Ask Replit or your agent to create a MotherDuck account
Tell the agent to load data into MotherDuck with a Flight
Ask for a Replit web app, backed by MotherDuck!
Tweak the look and feel with a few prompts or manually adjust with Replit’s Design mode
Click to deploy to production
To build something similar to the flight delay tracker I put together, try a prompt like:
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Sign up for MotherDuck (https://motherduck.com/blog/agent-signup/). Load 5 years of historical data using a MotherDuck Flight: * Flight delays from BTS Airline On-Time Performance data. Ex: (https://transtats.bts.gov/PREZIP/On_Time_Reporting_Carrier_On_Time_Performance_1987_present_2025_1.zip) * Weather forecast history by airport with the Iowa Environmental Mesonet (IEM) ASOS/METAR archive. Ex: (https://mesonet.agron.iastate.edu/cgi-bin/request/asos.py?) * US holidays. Ex: (https://date.nager.at/api/v3/PublicHolidays/2025/US) Create a web app on Replit that is backed by MotherDuck for exploring airline flight delay data and predicting delays. Pull live weather data from the national weather service API. Predict a user's delay by flight/route, holiday status, and current weather. Also show a map of flight routes and a histogram of historical delays. Let me filter by departure and arrival airport, carrier, and flight. Make the layout mobile and touch friendly.
I enjoyed Replit’s design features in particular. I was able to make manual tweaks, or just click on a part of the app to give to the agent as context. That way there was no more explaining exactly which section I was talking about. My workflow became: click on part of the app, then ask for the tweak I was looking for. The design feature also includes a lot of templates and ideas for customization:
I also had good success using even a lightweight model like GPT 5.6 Luna on max effort. We have previously found Luna max to be very efficient for analytics!
Of course, publication to a custom URL of my choice was a single click. It comes with autoscaling by default too.
It is very convenient for Replit to offer a free tier as well! MotherDuck lets you get started for free too (we have a Lite plan that starts at $0). Your agent can sign up for that free MotherDuck account with a dedicated agent endpoint, continue its testing, and then you can claim that account with a few clicks and an email verification. No need to hand your agent a credit card!
MotherDuck Flights also made it super simple for Replit to load all that historical data. I didn’t want to pull that on every page load, or load it into a transactional database that isn’t designed for things like bulk loads or full table reads. Flights are a serverless Python runtime with full access to any Python library, so anything Python can do, you can do on a Flight! It also has full internet access so you can download or scrape data from anywhere. Since it is serverless, it only pops into existence when you need to load data and costs nothing when you aren’t using it. It also means you don’t need to sign up for another tool - it’s built into MotherDuck.
All told, you get a fully serverless, scalable data app that you can test out for free and put into prod just as easily.
With a couple of clicks and prompts, you can have a data app fully deployed into production. Give MotherDuck and Replit a try! Just ask your agent.
2026/08/13 - Alex Monahan
Use an agent to build data apps with the combo of Vercel V0 and MotherDuck! V0 makes prototyping and deployment easy, while MotherDuck Flights provide seamless data ingestion and MotherDuck handles up to billions of rows. Your agent can even sign up for MotherDuck for you! See a full example app and the prompt that kickstarted it!
2026/08/13 - Simon Späti
The August 2026 DuckDB Ecosystem Newsletter: giving every agent its own embedded DuckDB, the ADBC extension reaching 30+ external databases, async I/O landing in v2.0, ISO GQL graph queries, Perspective 5.0 pushdown, plus a community spotlight on Kyle Cheung.
