Hard to check
You often can’t see the rows or the source until you download it.
Agents can now build any dataset in an afternoon. Mostly Right is where people and agents find and use the best ones.
THE SHIFT
02 / 11A good dataset used to need a data team and weeks of work. Now an agent does that work in an afternoon. So more datasets get built and shared than ever.
Over 1M public datasets on Hugging Face, roughly doubling every year. Source: Hugging Face Hub, Oct 2026
THE PROBLEM
03 / 11Builders ship them anywhere — Kaggle, Hugging Face, a personal drive — and there’s no common layer on top.
You often can’t see the rows or the source until you download it.
Answering one question can mean pulling down the whole file.
You can’t tell if it’s good without digging into who else uses it.
On Hugging Face, the top 1% of datasets get 77% of downloads. Most get almost none. Source: Hugging Face Hub stats, Oct 2026
THE SOLUTION
04 / 11Agents get the tools to build good datasets that are documented, searchable, and easy to query. Every dataset gets a public page and an audience of people and agents.
THE FLYWHEEL
05 / 11We start by rebuilding the most popular datasets from other platforms, fresher, searchable, and ready to query. Users follow, and publishers and data vendors follow them. Once vendors are here, paid datasets become a natural next step, listed right beside the free ones.
THE TEAM
06 / 11Twenty years ago Vu and Vojta built a mobile game together in high school. An exit and a PhD later, Vu met Rob at Marinade and introduced him to Vojta. The three of us teamed up to start Mostly Right in early 2026.

Built 13 dev tools that generated $1M in revenue, enough to bootstrap Avocode. Then took it through 500 Startups to $2M ARR before it was acquired.

Founded Cinnamon and raised a $3.9M seed for it. Then spent two years leading product at Marinade Finance, where he and Vu first worked together.

Took a masters at Imperial and a quantum computing PhD at Oxford, and is now at IBM Research. His first-author Nature paper has almost 4,000 citations.
TRACTION
07 / 11111 public datasets · 30 Sept 2026
DISCOVER DATASETS
08 / 11GitHub made code discoverable and the world built on it. We’re doing the same for datasets. Teams find us through the free catalogue, then explore and use the data through one API.
US Weather Reports and Daily Highs in 20 Cities
Kalshi settlement rules and sources, 2026
Kalshi hourly Bitcoin price order book, live
LLM benchmark scores by model, since 2019
Hourly rainfall and gauge history, U.S. cities, 2000–2026
Kalshi 15-minute BTC order book, fresh live
Movies and TV shows with plots, cast and ratings
Y Combinator company status and Form D filings
WHY WE BUILT THIS
09 / 11We built a data layer for our own models. Working with other teams showed us how much work it takes to make data usable, and keep it that way.
We built this data layer to trade prediction markets quantitatively, and our own strategies still run on it.
We opened it as an SDK. Every team told us it solves a real problem, but they need more data sources.
pip install mostlyrightmd
Adding sources by hand did not scale. We built agents to clean, join, and maintain the data those teams needed.
THE OPPORTUNITY
10 / 11Companies pay for data, then pay engineers to clean, integrate, and maintain it. We help teams build and publish datasets that others can discover, explore, and query.
LinkedIn lists about 190,000 data engineers, a Fivetran survey found they spend 44% of their time building and maintaining pipelines, and we assume a third of that is public data.
Our estimate · LinkedIn, 2024 · Fivetran, 2021Hedge funds buy most of it today, and banks and retailers are buying more each year.
Fortune Business Insights and Grand View Research, 2025THE VISION
11 / 11More datasets are being built than ever. We’re making every one of them easy to find, trust and use, so anyone, anywhere, can work with the world’s best data.