Jadpo is experimental and not ready for production. These docs follow the compiler's main branch as of 5 Nov 2026. What's built · Install 0.3.0
jadpo
ReferenceErrors

ErrorsEntities, stores and migrations · rule

data.store_required

On this page

An entity names no database to live in, and the app declares databases but none called main.

Area 5, Entities, stores and migrations; not declinable; the next step is usually the human's.

Why Jadpo refuses it

An entity lives in the main database unless its file says store: <connection>. With no database declared, main is a PostgreSQL database you don't have to declare. Once app.jadpo declares databases of its own, main is no longer implied, so an entity that names no store has nowhere to go.

Jadpo won't pick one of your databases for the entity, because that decides where its records are kept.

What it looks like

app.jadpo declares one database, archive:

domains/notes/entities/note.jadpo:

example
entity Note {    id: Uuid}
jadpo checkcheck failed: 1 error, 2 files

error Note names no store, and there is no main

--> domains/notes/entities/note.jadpo:1:8

  |1 | entity Note {  |        ^^^^ which store?
reason
An entity lives in main unless its file says store: <connection>, and app.jadpo declares no database called main; its databases are archive.
next
Add store: archive to Note (human)
rule
data.store_required
help
https://jadpo.dev/docs/errors/data.store_required

(human) at the end of the next: line tells your coding agent to stop and ask you which fix you want, because the choice is yours to make: it decides which database keeps notes.

How to fix it

If notes belong in archive, say so in the entity. domains/notes/entities/note.jadpo becomes:

example
entity Note {    id: Uuid    store: archive}

Notes are kept in the archive database.

If notes belong in a database of their own, declare main beside archive in app.jadpo:

example
        main: {            driver: Driver.postgres        }

Notes, and every other entity that names no store, are kept in main.

Markdown for agents: /docs/errors/data.store_required.md.Built from Jadpo main at aee2e8f.