Development

This guide covers the development workflow for building Kit applications, including the dev server, hot reloading, and useful commands.

Development Server

Start the development server with:

kit serve

This starts:

Backend server on http://localhost:8080
Vite dev server on http://localhost:5173 (for frontend assets)

Backend Only Mode

If you only need the Rust backend (no frontend):

kit serve --backend-only

Custom Ports

Configure ports using environment variables:

# .env
PORT=3000
VITE_DEV_SERVER=http://localhost:5174

Project Structure

A typical Kit project structure:

my-app/
├── src/
│   ├── main.rs           # Application entry point
│   ├── routes.rs         # Route definitions
│   ├── controllers/      # Request handlers
│   ├── models/           # Database entities
│   ├── actions/          # Business logic
│   └── middleware/       # Custom middleware
├── frontend/
│   ├── src/
│   │   ├── main.tsx      # Frontend entry
│   │   └── pages/        # React components
│   ├── package.json
│   └── vite.config.ts
├── migrations/           # Database migrations
├── .env                  # Environment config
└── Cargo.toml

Development Workflow

1. Make Changes

Edit your Rust code in src/ or React code in frontend/src/.

2. Automatic Recompilation

Kit watches for changes:

Rust changes: Recompiles automatically
React changes: Hot module replacement (instant updates)

3. Test Your Changes

Visit http://localhost:8080 to see your changes.

Database Development

Running Migrations

# Run all pending migrations
kit migrate

# Check migration status
kit migrate:status

# Rollback last migration
kit migrate:rollback

Syncing Entities

After modifying migrations, regenerate entity files:

kit db:sync

Fresh Database

Reset and re-run all migrations:

kit migrate:fresh

Code Generation

Kit provides generators to scaffold common components:

# Create a controller
kit make:controller users

# Create a model
kit make:model User

# Create a migration
kit make:migration create_posts_table

# Create a page component
kit make:page Home

# Generate TypeScript types
kit generate-types

Environment Configuration

Configure your app using .env:

# Server
PORT=8080

# Database
DATABASE_URL=sqlite:./database.db

# Inertia/Frontend
INERTIA_DEVELOPMENT=true
VITE_DEV_SERVER=http://localhost:5173

Debugging

Logging

Kit uses Rust’s standard logging. Enable debug output:

RUST_LOG=debug kit serve

Database Queries

Enable SQL query logging:

RUST_LOG=sea_orm=debug kit serve

Testing

Run your test suite:

cargo test

Frontend Tests

cd frontend
npm test

Building for Production

Build the Backend

cargo build --release

Build the Frontend

cd frontend
npm run build

Run Production Server

INERTIA_DEVELOPMENT=false ./target/release/your-app

Useful Commands

Command	Description
`kit serve`	Start dev server
`kit serve --backend-only`	Start without Vite
`kit migrate`	Run migrations
`kit migrate:fresh`	Reset database
`kit db:sync`	Regenerate entities
`kit make:controller <name>`	Create controller
`kit make:model <name>`	Create model
`kit generate-types`	Generate TS types
`cargo build --release`	Production build

Getting Started

Tutorials

Core Concepts

Frontend

Database

CLI Reference

Deployment

Development Server

Backend Only Mode

Custom Ports

Project Structure

Development Workflow

1. Make Changes

2. Automatic Recompilation

3. Test Your Changes

Database Development

Running Migrations

Syncing Entities

Fresh Database

Code Generation

Environment Configuration

Debugging

Logging

Database Queries

Testing

Frontend Tests

Building for Production

Build the Backend

Build the Frontend

Run Production Server

Useful Commands

​Development Server

​Backend Only Mode

​Custom Ports

​Project Structure

​Development Workflow

​1. Make Changes

​2. Automatic Recompilation

​3. Test Your Changes

​Database Development

​Running Migrations

​Syncing Entities

​Fresh Database

​Code Generation

​Environment Configuration

​Debugging

​Logging

​Database Queries

​Testing

​Frontend Tests

​Building for Production

​Build the Backend

​Build the Frontend

​Run Production Server

​Useful Commands

Development Server

Backend Only Mode

Custom Ports

Project Structure

Development Workflow

1. Make Changes

2. Automatic Recompilation

3. Test Your Changes

Database Development

Running Migrations

Syncing Entities

Fresh Database

Code Generation

Environment Configuration

Debugging

Logging

Database Queries

Testing

Frontend Tests

Building for Production

Build the Backend

Build the Frontend

Run Production Server

Useful Commands