Project Structure

After running ferriorm init and ferriorm migrate dev, your project will have the following layout:

my-project/
├── Cargo.toml
├── schema.ferriorm        ← your schema
├── migrations/            ← auto-generated SQL
│   └── 0001_init/
│       ├── migration.sql
│       └── _schema_snapshot.json
└── src/
    ├── main.rs
    └── generated/         ← auto-generated Rust code
        ├── mod.rs
        ├── client.rs
        ├── user.rs
        └── enums.rs

schema.ferriorm

The schema file is the single source of truth for your data model. It defines:

• Datasource – which database provider to use and how to connect
• Generator – where to output the generated Rust code
• Models – your tables, fields, relations, and indexes
• Enums – shared enum types used across models

datasource db {
  provider = "postgresql"
  url      = env("DATABASE_URL")
}

generator client {
  output = "./src/generated"
}

model User {
  id    String @id @default(uuid())
  email String @unique
  name  String?
  posts Post[]

  @@map("users")
}

model Post {
  id       String @id @default(uuid())
  title    String
  author   User   @relation(fields: [authorId], references: [id])
  authorId String

  @@map("posts")
}

You edit this file, then run ferriorm migrate dev to sync everything.

migrations/

Each migration lives in a numbered directory. ferriorm creates these automatically when you run ferriorm migrate dev --name <name>.

migrations/
├── 0001_init/
│   ├── migration.sql           ← the SQL that was applied
│   └── _schema_snapshot.json   ← schema state after this migration
└── 0002_add_posts/
    ├── migration.sql
    └── _schema_snapshot.json

• migration.sql – The SQL statements that create or alter tables. You can review and edit these before applying. ferriorm tracks checksums to detect manual edits.
• _schema_snapshot.json – A JSON snapshot of the schema at this point in time. Used by the snapshot migration strategy for offline diffing.

Tip: Commit the entire migrations/ directory to version control. These files are how your teammates and production environments apply the same schema changes.

src/generated/

This directory contains the Rust code that ferriorm generates from your schema. Do not edit these files – they are overwritten every time you run ferriorm generate or ferriorm migrate dev.

Each model file follows the same structure:

#![allow(unused)]
fn main() {
// In generated/user.rs (simplified)

pub struct User {
    pub id: String,
    pub email: String,
    pub name: Option<String>,
    // ...
}

pub mod data {
    pub struct UserCreateInput { /* required + optional fields */ }
    pub struct UserUpdateInput { /* all fields optional */ }
}

pub mod filter {
    pub struct UserWhereInput { /* filterable fields */ }
    pub enum UserWhereUniqueInput { /* unique fields */ }
}

pub mod order {
    pub enum UserOrderByInput { /* orderable fields */ }
}
}

To use the generated code, add mod generated; at the top of your main.rs (or lib.rs).

Typical workflow

1. Edit schema.ferriorm
2. Run ferriorm migrate dev --name describe_the_change
3. The CLI diffs, generates a migration, applies it, and regenerates src/generated/
4. Your Rust code gets compile-time errors if anything changed – fix and continue

Next steps

• See the full Schema Reference for all available model attributes and field types
• Learn about CRUD Operations available on the generated client