Intermediate Representation

The IR is JSON stored at .fastbackend/ir.json. It is the contract between @fastbackend/core and runtime adapters.

Root Structure

{
  "version": "1.0.0",
  "metadata": {
    "projectName": "my-api",
    "schemaFormat": "sqlalchemy",
    "adapter": "fastapi",
    "generatedAt": "2026-01-01T00:00:00.000Z",
    "schemaVersion": "1.0.0"
  },
  "entities": [],
  "relationships": [],
  "enums": []
}

Entity

Field

{
  "name": "email",
  "type": { "base": "string", "format": "email" },
  "nullable": false,
  "defaultValue": null,
  "validation": [{ "type": "required" }],
  "metadata": {}
}

Type bases: string, integer, float, boolean, date, datetime, json, enum, array

Formats: email, uuid, url

Relationship

{
  "name": "posts",
  "type": "one-to-many",
  "sourceEntity": "User",
  "targetEntity": "Post",
  "sourceField": "id",
  "targetField": "user_id",
  "cascadeDelete": false,
  "metadata": { "backPopulates": "author" }
}

Types: one-to-one, one-to-many, many-to-one, many-to-many

Validation Rules