Advent of Code 🎄

Solutions for Advent of Code using Bun and Effect-TS.

Tech Stack

• Runtime: Bun - Fast JavaScript runtime
• Language: TypeScript (bleeding edge)
• Framework: Effect-TS - Functional programming library
• Linting/Formatting: Biome - Fast, modern linter and formatter
• Editor: VS Code with DevContainer/Codespaces support

Getting Started

Prerequisites

• Bun installed, or
• VS Code with Dev Containers extension, or
• A GitHub account (for Codespaces)

Using GitHub Codespaces (Easiest)

1. Click the "Open in GitHub Codespaces" badge above, or
2. Go to the repository on GitHub and click "Code" → "Codespaces" → "Create codespace on main"
3. Wait for the codespace to start - dependencies will be installed automatically

Using DevContainer (Local)

1. Open this repository in VS Code
2. Press F1 and select "Dev Containers: Reopen in Container"
3. Wait for the container to build and dependencies to install

Local Setup

# Install dependencies
bun install

# Run a specific day (e.g., 2025 day 1)
bun run src/bin.ts run 2025 1

Scripts

# Run specific day
bun run src/bin.ts run <year> <day>

# Example: Run 2025 day 1
bun run src/bin.ts run 2025 1

# Linting
bun run lint        # Check for lint errors
bun run lint:fix    # Fix lint errors

# Formatting
bun run format       # Format code
bun run format:check # Check formatting

# Type checking
bun run typecheck

# All checks
bun run check       # Run all checks
bun run check:fix   # Fix all auto-fixable issues

Project Structure

src/
├── bin.ts             # Main entry point
├── Cli.ts             # CLI implementation
└── <year>/            # Year directories (e.g., 2025/)
    └── <day>/         # Day directories (e.g., 01/)
        ├── index.ts   # Day solution
        ├── index.test.ts # Tests
        └── input.txt  # Puzzle input

VS Code Extensions

Required extensions will be automatically recommended when you open the project:

• Effect VS Code - Language support for Effect-TS
• Biome - Linting and formatting
• Bun - Bun runtime support

License

MIT