Saeril

Source Model

• Databases.
• Entities.
• Enums.
• Indexes scoped to entities.
• Migration blocks.

Modules

• Exactly one module declaration is allowed per file.
• Module names use dot-separated identifiers.
• The module name participates in emitted VTI type_id values.

Databases

database postgres "main" {  extension "uuid-ossp"}

Entities

• Entity names use PascalCase.
• The table clause is required for persisted entities.
• Table names are quoted strings.
• Field names use snake_case.
• Each entity emits a VTI record or row declaration with facts.storage.relational.
• Field order is stable and is preserved in VTI.

entity User table "users" {  id: Uuid @primary  email: String @unique @max(320)  display_name: String? @max(120)  status: UserStatus @default(active)}

Field Declarations

• At least one primary key field is required per persisted entity.
• Multiple @primary fields form a composite primary key in declaration order.
• Primary fields are required and cannot be nullable.
• N must be a positive integer.
• @max is valid only on String.
• The value maps to VTI scalar String.max_length.
• Defaults must type-check against the field type.
• Provider functions such as now() must be supported by the selected database provider.

id: Uuid @primaryemail: String @unique @max(320)deleted_at: DateTime?account_id: Uuid @ref(Account.id) @on_delete(restrict)total: Decimal(12, 2) @check("total >= 0") @indextags: Text[]metadata: Jsonb?shipping_address: Struct { city: Text zip: String? }display_name: Text @generated("email")

Enums

• Enum names use PascalCase.
• Variants use snake_case.
• Variant order is stable and emitted to VTI.
• Removing or renaming a variant is a breaking change.
• Adding a variant may be breaking for exhaustive consumers unless policy allows unknown handling.

enum UserStatus {  active  suspended  archived}

Indexes

• SQL index names are emitted as idx_{table}_{NAME}.
• Fields must exist on the entity.
• Field order is preserved.
• where creates a partial index and is emitted to VTI as where.
• Partial predicates must reference fields on the entity and type-check as boolean expressions.

entity User table "users" {  id: Uuid @primary  email: String @max(320)  deleted_at: DateTime?   index active_email on (email) where deleted_at == null  index deleted_at_desc on (deleted_at desc)}

Entity Constraints

• check NAME ("PREDICATE") emits a named table-level CHECK.
• unique NAME on (FIELD_LIST) emits a composite unique index named uq_{table}_{NAME}.
• Constraint names must be unique within the entity.
• Unique fields must exist on the entity.

entity Invoice table "invoices" {  id: Uuid @primary  account_id: Uuid  invoice_number: String  total: Decimal(12, 2)   check positive_total ("total >= 0")  unique account_invoice on (account_id, invoice_number)}

Seed Data

entity Plan table "plans" {  id: Uuid @primary  code: Text @unique  name: Text   seed {    row { id: "018f", code: "free", name: "Free" }    row { id: "0190", code: "pro", name: "Pro" }  }}