| | |

A modern, type-safe Scala 3 wrapper library for DuckDB that provides idiomatic, functional programming-friendly access to DuckDB's analytical database capabilities through its Java JDBC client.

Duck4s makes working with DuckDB in Scala applications a pleasant experience by:

• Providing type-safe APIs that leverage Scala 3's advanced type system
• Supporting functional programming patterns with Either[DuckDBError, T] error handling
• Offering automatic resource management with withConnection, withPreparedStatement, and withBatch methods
• Maintaining full compatibility with DuckDB's JDBC interface while providing idiomatic Scala abstractions

• 🦆 Type Safety - Comprehensive error handling with Either[DuckDBError, T] types
• 🔧 Resource Management - Automatic resource cleanup with withConnection, withPreparedStatement, and withBatch methods
• 🚀 Functional Programming - Designed for composition with for-comprehensions and functional patterns
• 📊 Modern Scala 3 - Utilizes Scala 3 features like extension methods, given instances, and braceless syntax
• 🔄 Batch Operations - Efficient type-safe batch processing with type classes
• 💼 Transaction Support - First-class transaction management with automatic rollback
• 📱 LTS and Latest Scala Version Support - Supports Scala 3.3.6 (LTS) and 3.7.0

Add duck4s to your build.sbt:

libraryDependencies += "com.softinio" %% "duck4s" % "0.1.1"

Add duck4s to your build.mill:

def ivyDeps = Agg(
  ivy"com.softinio::duck4s::0.1.1"
)

• Scala 3.3.6 or 3.7.0
• Java 17 or higher
• Mill build tool (or use the provided Nix development environment)

This project uses Nix for reproducible development environments. To get started:

# Enter the development shell (requires Nix with flakes)
nix develop

# Build for all Scala versions
mill __.compile

# Build for specific Scala version
mill 'duck4s[3.7.0].compile'

# Run tests
mill __.test

# Generate documentation
mill 'duck4s[3.7.0].docJar'

# Format code
mill mill.scalalib.scalafmt.ScalafmtModule/reformatAll __.sources

# Clone the repository
git clone https://github.com/softinio/duck4s.git
cd duck4s

# Build the project
mill __.compile

# Run tests
mill __.test

import com.softinio.duck4s.*
import com.softinio.duck4s.algebra.*

// Simple query execution
val result = DuckDBConnection.withConnection() { conn =>
  for
    _ <- conn.executeUpdate("CREATE TABLE users (id INTEGER, name VARCHAR)")
    _ <- conn.executeUpdate("INSERT INTO users VALUES (1, 'Alice'), (2, 'Bob')")
    rs <- conn.executeQuery("SELECT * FROM users ORDER BY id")
  yield
    while rs.next() do
      println(s"${rs.getInt("id")}: ${rs.getString("name")}")
    rs.close()
}

result match
  case Right(_) => println("Query executed successfully")
  case Left(error) => println(s"Error: $error")

• Getting Started Guide - Learn the basics of duck4s
• API Documentation - Complete API reference

GitHub Issues are disabled to encourage direct community contribution. When you encounter bugs or documentation issues, please contribute fixes through Pull Requests instead.

How to contribute: Open a PR with your solution, draft changes, or a test reproducing the issue. We'll collaborate from there to refine and merge improvements.

This approach creates faster fixes while building a stronger, community-driven project where everyone benefits from shared contributions.

This project is optimized and setup for you to use Claude Code as your AI programming agent. It is recommended to use Claude Code.

Duck4s is licensed under the Apache License 2.0. See LICENSE for details.

• DuckDB for creating an excellent analytical database
• The Scala community for continuous innovation in functional programming