Protocols
How the data was made. A Protocol is a reproducible recipe: an ordered sequence of typed steps that fetch, transform and export data. The first set below build Meridian’s open Datasets; the example Protocols further down build well-known public datasets on your own disk. Every step is a versioned operator, a SQL model, or (rarely) an opaque command, and a Protocol can gate its output against a finetype schema contract before it ships.
Running a Protocol you did not write is equivalent to running a shell script you did not read. Arcform runs a step’s command as you, with no sandbox and no container, and the finetype gate checks the data a Protocol produces, not what its steps do. What running one costs you.
This is a read-only view for browsing and discovery — authoring lives elsewhere.
EDGAR ↔ GLEIF — Company-to-LEI Crosswalk
Resolve SEC companies to their GLEIF LEI: a deterministic fund backbone unioned with a probabilistic name match, tiered by confidence.
SEC EDGAR — Company Tickers
Ingest the SEC company_tickers_exchange.json into a typed, reproducible Parquet — information retrieval only.
NAICS — Industry Classification
Ingest the U.S. Census 2022 NAICS descriptions workbook into a typed, reproducible Parquet.
GLEIF — Legal Entity Identifiers
Ingest the GLEIF golden-copy full-file CSV into a typed, reproducible Parquet — the one Protocol with an opaque fetch, by design.
Example Protocols
Recipes over well-known public datasets. Meridian hosts none of them; each downloads its data, from the address its fetch step names, when you run it.

USGS Earthquakes 2025
The earthquakes of magnitude 4.5 and up that the US Geological Survey's own network reported in 2025, from the USGS earthquake catalogue.

NYC Yellow Taxi Trips
Every yellow taxi trip the New York City Taxi and Limousine Commission recorded as picked up in January 2026, read from the TLC's own monthly file.

Epoch AI Notable AI Models
Epoch AI's database of notable AI models: when each was published, its first-listed domain, its training compute and how that compute is known, the kind of organisation behind it, and how the model can be reached.

Census Income (Adult)
The standard 'Adult' benchmark extract of the 1994 US Census: 32,561 person records with demographic and employment attributes and an income label, '<=50K' or '>50K'.

Online Retail II
The invoices of a UK-based online retailer of giftware, many of whose customers are wholesalers, from 1 December 2009 to 9 December 2011, as the UCI Machine Learning Repository publishes them.

California Housing
20,640 California districts (census block groups) from the 1990 Census, each with its median income, housing age, average rooms and occupancy, population, latitude and longitude, and median house value.

Movies (vega-datasets)
3,201 films from vega-datasets, with production budget, US and worldwide gross, DVD sales, running time, distributor, director, genre and two critic scores.

Palmer Penguins
Bill length and depth, flipper length, body mass and sex for 344 Adélie, Chinstrap and Gentoo penguins on three islands near Palmer Station, Antarctica, from 2007 to 2009.
ScienceQA
ScienceQA is a set of multiple-choice science questions with worked explanations, published by Pan Lu and colleagues with their NeurIPS paper, 'Learn to Explain: Multimodal Reasoning via Thought Chains for Science Question Answering'.

MedMCQA
MedMCQA is a set of multiple-choice questions from medical entrance exams, published by Pal, Umapathi and Sankarasubbu at CHIL 2022.

SuperGPQA
26,529 graduate-level multiple-choice questions spanning 13 disciplines, 72 fields and 285 subfields, each with four to ten answer options, the correct answer, a difficulty label and whether it requires calculation.