Effect SQLType-safe, composable SQL for Effect

Write SQL queries that are safe, efficient, and integrate seamlessly with the Effect ecosystem

🔒

Type-Safe by Design

Write SQL with full TypeScript type safety. Catch errors at compile time, not runtime. Integrate with Effect Schema for validated, decoded results.

⚡

Zero Boilerplate

Use tagged template literals to write SQL naturally. Automatic parameter binding, query escaping, and result transformation—no ORM overhead.

🔄

First-Class Transactions

Transactions are composable and automatic. Nest transactions with savepoints, handle rollbacks gracefully, and never worry about connection leaks.

🗄️

Multi-Database Support

PostgreSQL, SQLite, MySQL, SQL Server, ClickHouse, Cloudflare D1, LibSQL—all with the same elegant API. Switch databases without rewriting code.

📦

Built-in Migrations

Version your database schema with Effect-native migrations. Run them as part of your application startup or as a separate process.

🚀

Batching & Data Loaders

Solve the N+1 problem elegantly with built-in request batching. Perfect for GraphQL resolvers and any scenario with repeated queries.

Quick Example

typescript

import { Effect } from "effect"
import { SqlClient } from "@effect/sql"
import { PgClient } from "@effect/sql-pg"

// Create a query - it's just a tagged template literal
const findUserById = (id: number) =>
  Effect.gen(function* () {
    const sql = yield* SqlClient.SqlClient
    
    const users = yield* sql<{ id: number; name: string; email: string }>`
      SELECT id, name, email 
      FROM users 
      WHERE id = ${id}
    `
    
    return users[0]
  })

// Run with proper resource management
const program = findUserById(1).pipe(
  Effect.provide(PgClient.layer({
    host: "localhost",
    database: "myapp"
  }))
)

Effect.runPromise(program)

Why Effect SQL?

Effect SQL is designed from the ground up to work with the Effect ecosystem. This means:

Automatic resource management - Connections are acquired and released automatically
Structured error handling - SQL errors are properly typed and handled
Observability built-in - Queries emit spans for tracing automatically
Composable - Build complex queries from simple, reusable pieces

Ready to dive in? Start with the Introduction to learn the fundamentals.

Effect SQLType-safe, composable SQL for Effect

Type-Safe by Design

Zero Boilerplate

First-Class Transactions

Multi-Database Support

Built-in Migrations

Batching & Data Loaders

Quick Example ​

Why Effect SQL? ​

Quick Example

Why Effect SQL?