Hindsight: Type-Safe Event Sourcing Documentation

Welcome to Hindsight, a type-safe event sourcing system implemented in Haskell. Hindsight provides strong compile-time guarantees for event handling, versioning, and consistency in event-driven applications with multiple storage backends.

Overview

Hindsight provides type-safe event sourcing with:

• Compile-time event versioning and automatic upgrades

• Multiple storage backends (Memory, Filesystem, PostgreSQL)

• Backend-agnostic projections for building read models

• Real-time event subscriptions with pattern matching

All with strong event ordering guarantees, multi-stream consistency features and a polished API.

Hindsight is currently experimental, and bugs are to be expected. Bug reports, critics, suggestions are all welcome on our issue tracker.

Quick Start

Learning: Check out the Tutorials for a step-by-step introduction. Visit the Hindsight example repository for a quick demonstration.

Using Hindsight in my project: See Installation.

Contributing: For development setup, see Development Guide.

Documentation Contents

Getting Started

• Installation
  • Two Ways to Add Hindsight
  • Option A: With Nix Flakes
  • Option B: Without Nix
  • Available Packages
  • Basic Usage
  • PostgreSQL Setup
  • Example Project
  • Next Steps

Tutorials

• Tutorials
  • 1. Getting Started with Hindsight
  • 2. In-Memory Projections
  • 3. PostgreSQL Projections
  • 4. Event Versioning
  • 5. Consistency Patterns
  • 6. Backend-Agnostic Code
  • 7. Synchronous Projections
  • 8. Cross-Stream Consistency

API Reference

• API Reference
  • Package Documentation
  • Generating API Documentation

Development

• Development Guide

Indices and tables

• Index

• Module Index

• Search Page