Software Design and Architecture in Haskell

A structured set of materials on how to build real-world applications in Haskell.

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Table of Contents

• Books on Software Architecture in Haskell
• Application Architectures
• Design Approaches and Design Patterns
  • Free Monads
  • Final Tagless / mtl
  • Effect Systems
  • ReaderT Pattern
  • Service Handle Pattern
  • Other Patterns
  • OOP Design Patterns vs FP Design Patterns
• Comparison of Approaches
  • Comparison Table
• Design Principles
• Methodologies and Phylosophy
• Best Practices & Guidelines
• Testing
• Showcase Projects & Code Orgranization Samples
• Haskell in Production. Success Stories, Experience Reports
• Talks
• Haskell Ecosystem and Accessibility
  • Haskell Ecosystem
  • Haskell Community
  • Haskell Learn: Books

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Books on Software Architecture in Haskell

• Functional Design and Architecture | Alexander Granin
• Practical Haskell. A Real World Guide to Programming | Serrano, Alejandro
• Real World Haskell | Bryan O'Sullivan, Don Stewart, John Goerzen

Application Architectures

• Three Layer Haskell Cake | Matt Parsons
• A Modern Architecture for FP | John A De Goes
• Hexagonal Architecture and Free Monad: Two related design patterns?
• Anatomy of a Haskell-based Application
• Architecture of a Real World Haskell Application
• A Dead-Simple Web Stack In Haskell | Showcase | William Yao
• Large-scale design in Haskell? (SO question)

Design Approaches and Design Patterns

Free Monads

• Why free monads matter | Gabriel Gonzalez
• Free monads in 7 easy steps
• A Modern Architecture for FP | John A De Goes
• Building network actors with Node Framework | Alexander Granin
• Automatic White-Box Testing with Free Monads | Alexander Granin | Showcase
• Hierarchical Free Monads and Software Design in Functional Programming (Talk) | Slides | Alexander Granin | FunctionalConf 2019, Bangalore, India
• Strict typing fun example — Free Monads in Haskell
• Free Monads: from the basics to the implementation of composable and effectful stream processing
• What does Free buy us? | Matt Parsons
• What is the “Free Monad + Interpreter” pattern?
• Combining free monads in Haskell | Mark Seemann

Final Tagless / mtl

• Tagless Final Encoding in Haskell | Juan Pablo Royo
• Introduction to Tagless Final | Vasiliy Kevroletin | Serokell
• Reducing boilerplate in finally tagless style | Roman Cheplyaka
• Tagless Final Encoding of a Test Language

Effect Systems

ReaderT Pattern

• The ReaderT Design Pattern | Michael Snoyman
• The ReaderT design pattern or tagless final? | Magnus Therning
• Capability: The ReaderT Pattern Without The Boilerplate

Service Handle Pattern

• The Service Pattern | Simon Meier
• Haskell Design Patterns: The Handle Pattern | Jasper Van der Jeugt

Other Patterns

• (Book) Haskell Design Patterns | Ryan Lemmer
• Enterprise Haskell Pattern: Lensed Reader | Michael Xavier
• The Has Type Class Pattern | Jonathan Fischoff
• Type Class Patterns and Anti-patterns | Jonathan Fischoff

OOP Design Patterns vs FP Design Patterns

• Lambda the Ultimate Pattern Factory

Comparison of Approaches

• Which Type-Safe Database Library Should You Use? | William Yao
• Final Tagless vs Free Monad (Talk, Rus) | Slides (Eng) | Alexander Granin | FPure 2019, Kazan
• Monad transformers, free monads, mtl, laws and a new approach
• Backpack for initial and final encodings
• Capability: The ReaderT Pattern Without The Boilerplate

Comparison Table

• Haskell Approaches Comparison Table

Phylosophy

• Boring Haskell Manifesto | Michael Snoyman | Reddit discussion
• The Haskell Pyramid

Design Principles

• Rule of Least Power
• SOLID
• KISS
• YAGNI
• DRY

Best Practices & Guidelines

• Figuring Out How To Use Beam For DB Migrations | Willam Yao
• Haskell practices
• An opinionated guide to Haskell in 2018 | Lexi Lambda
• Getting things done in Haskell (Talk) | Jasper Van der Jeugt | HaskellerZ, Feb 2018
• Working around Haskell's namespace problem for records | Moritz Clasmeier
• Programming guidelines
• Kowainik's Haskell Style Guide
• Tweag.IO's Haskell Style Guide
• Tibbe's Haskell Style Guide

Testing

Showcase Projects & Code Orgranization Samples

Haskell in Production. Success Stories, Experience Reports

• The Joy and Agony of Haskell in Production | Stephen Diehl
• Haskell is Not For Production and Other Tales (Talk) | Katie Miller
• Production Haskell (Talk) | Reid Draper
• Haskell in Production
  • Haskell in Production
  • Designing Testable Components
• Haskell in Production | Hasura.IO
• 5 Years of Haskell in Production (Talk) | Alexander Thiemann
• Retrospective: Haskell in Production
• My “Haskell In Production” Story | David Joyner

Talks

• Getting things done in Haskell (Talk) | Jasper Van der Jeugt | HaskellerZ, Feb 2018
• Hierarchical Free Monads and Software Design in Functional Programming (Talk) | Slides | Alexander Granin | FunctionalConf 2019, Bangalore, India
• Final Tagless vs Free Monad (Talk, Rus) | Slides (Eng) | Alexander Granin | FPure 2019, Kazan
• Haskell is Not For Production and Other Tales (Talk) | Katie Miller
• Production Haskell (Talk) | Reid Draper
• 5 Years of Haskell in Production (Talk) | Alexander Thiemann

Haskell Ecosystem and Accessibility

This section is aimed to show that learning and using Haskell is not as horrible as some folks are trying to claim.

Haskell Ecosystem

• State of the Haskell ecosystem | Gabriel Gonzalez

Haskell Community

• The Haskell Pyramid

Haskell Learn: Books

• Get Programming with Haskell | Will Kurt
• Haskell in Depth | Vitaly Bragilevsky
• What I Wish I Knew When Learning Haskell | Stephen Diehl
• Haskell from the Very Beginning | John Whitington
• Learn You a Haskell for Great Good! | Miran Lipovača
• Programming in Haskell | Graham Hutton
• Practical Haskell. A Real World Guide to Programming | Serrano, Alejandro
• Parallel and Concurrent Programming in Haskell: Techniques for Multicore and Multithreaded Programming | Simon Marlow
• Real World Haskell | Bryan O'Sullivan, Don Stewart, John Goerzen
• Functional Design and Architecture | Alexander Granin