Generator Overview

Seedling automatically assigns a generator to every column based on its type, name, and constraints. You can override any column with custom generators via a YAML file.

Auto-Detection

When you run seedling generate without overrides, Seedling inspects each column and selects a generator:

Schema Signal	Detected Generator
`serial` / `bigserial` PK	Sequence
FK column	FK pool lookup
`varchar` / `text`	Random string
`varchar` named “email”	`Email`
`varchar` named “phone”	`Phone`
`varchar` named “url”	`URL`
`boolean` / `tinyint(1)`	`Bool`
`timestamptz` / `timestamp`	`Now` / `Timestamp`
`date`	`DateGenerator`
`numeric` / `decimal`	`Numeric`
`float` / `double`	`FloatRange`
`uuid`	`UUID`
`json` / `jsonb`	Random JSON
`enum`	Random enum value
`unique` column	Unique constrained variant

Hint System

Column comments in the database schema can provide hints to Seedling:

COMMENT ON COLUMN users.role IS 'generator:weighted_choice';

These hints are stored in the schema file and influence generator selection during auto-detection.

Override System

For full control, provide a generator overrides YAML file to override specific columns.