124 Decks Ordered By Publication Date - Latest First - Chse one - invert order

# Title Published
1 The Bowling Game - From Imperative to Functional Programming - Part 3 11 Oct 2026  
2 The Bowling Game - From Imperative to Functional Programming - Part 2 06 Sep 2026  
3 The Bowling Game - From Imperative to Functional Programming - Part 1 06 Jul 2026  
4 Imperative Bowling Kata - 20 Years On - Delegating Menial Tasks to Github Copilot Chat - using Scala in IntelliJ IDEA 29 Mar 2026  
5 Imperative Bowling Kata - 20 Years On - Delegating Menial Tasks to AI Coding Tool 'Claude Code' 15 Feb 2026  
6 AI Concepts - MCP Neurons 02 Jan 2026  
7 Combinatorial Interview Problems with Backtracking Solutions - from Procedural to Functional Programming - Part 2 14 Dec 2025  
8 Combinatorial Interview Problems with Backtracking Solutions - from Procedural to Functional Programming - Part 1 16 Nov 2025  
9 Test Doubles - Terminology, Definitions and Illustrations - with Examples - Part 1 14 Sep 2025  
10 ApplicativeError functions handling and recovering from errors: A mnemonic to recall their signatures from their names 11 Aug 2025  
11 Folding Cheat Sheet #9 - List Unfolding - 'unfold' as the Computational Dual of 'fold', and how 'unfold' relates to 'iterate' 15 Jun 2025  
12 List Unfolding - 'unfold' as the Computational Dual of 'fold', and how 'unfold' relates to 'iterate' 31 May 2025  
13 Drawing Heighway’s Dragon - Part 4 - Interactive and Animated Dragon Creation 18 May 2025  
14 The Nature of Complexity in John Ousterhout’s Philosophy of Software Design 21 Apr 2025  
15 Drawing Heighway’s Dragon - Part 3 - Simplification Through Separation of Concerns - Rotation Without Matrix Multiplication 13 Apr 2025  
16 Drawing Heighway’s Dragon - Part 2 - Recursive Function Simplification - From 2^n Recursive Invocations To n Tail-Recursive Invocations Exploiting Self-Similarity 29 Mar 2025  
17 Drawing Heighway’s Dragon - Part 1 - Recursive Function Rewrite - From Imperative Style in Pascal 64 To Functional Style in Scala 3 02 Mar 2025  
18 Fibonacci Function Gallery - Part 2 27 Dec 2024  
19 Fibonacci Function Gallery - Part 1 15 Dec 2024  
20 The Debt Metaphor - Ward Cunningham in his 2009 YouTube video 23 Nov 2024  
21 From Subtype Polymorphism To Typeclass-based Ad hoc Polymorphism - An Example 27 Oct 2024  
22 Folding Cheat Sheet #8 - Folding with monoids 13 Oct 2024  
23 Function Applicative for Great Good of Leap Year Function 14 Aug 2024  
24 Folding Cheat Sheet #7 - The three duality theorems of fold 07 Jul 2024  
25 Folding Cheat Sheet #6 - Left and right folds and tail recursion 23 Jun 2024  
26 Folding Cheat Sheet #5 - Folding a list right and left using Cons and Nil results in the identity and reverse functions 22 Jun 2024  
27 Hand Rolled Applicative User Validation Code Kata 09 Jun 2024  
28 A Sighting of filterA in Typelevel Rite of Passage 03 Jun 2024  
29 Direct Style Effect Systems - The Print[A] Example - A Comprehension Aid 06 May 2024  
30 Folding Cheat Sheet #4 - For functions that can be defined both as a right fold and as a left fold, one may be more efficient than the other 21 Apr 2024  
31 Folding Cheat Sheet #3 - The universal property of fold 02 Apr 2024  
32 Folding Cheat Sheet #2 - Programmatic and mathematical definitions of right fold and left fold 30 Mar 2024  
33 Folding Cheat Sheet #1 - Folding over recursively defined data structures for natural numbers and lists 29 Mar 2024  
34 Folding Cheat Sheet Series Titles 28 Mar 2024  
35 Scala Left Fold Parallelisation - Three Approaches 19 Nov 2023  
36 Tagless Final Encoding - Algebras and Interpreters and also Programs 22 Oct 2023  
37 Fusing Transformations of Strict Scala Collections with Views 15 Oct 2023  
38 A sighting of traverse_ in Practical FP in Scala 08 Oct 2023  
39 A sighting of traverseFilter and foldMap in Practical FP in Scala 01 Oct 2023  
40 A sighting of sequence function in Practical FP in Scala 24 Sep 2023  
41 N-Queens Combinatorial Puzzle meets Cats 03 Aug 2023  
42 Kleisli composition, flatMap, join, map, unit - implementation and interrelation - V2 updated for Scala 3 04 Jun 2023  
43 The aggregate function - from sequential and parallel folds to parallel aggregation 25 Sep 2022  
44 Nat, List and Option Monoids - From scratch - Combining and Folding - An example 01 Aug 2022  
45 The Sieve of Eratosthenes - Part 2 - Genuine versus Unfaithful Sieve 24 Jul 2022  
46 Sum and Product Types - The Fruit Salad & Fruit Snack Example 03 Jul 2022  
47 Algebraic Data Types for Data Oriented Programming - From Haskell and Scala to Java 26 Jun 2022  
48 Defining filter using (a) recursion (b) folding (c) folding with S, B and I combinators (d) folding with applicative functor and identity function 28 May 2022  
49 The Sieve of Eratosthenes - Part 1 15 May 2022  
50 The Uniform Access Principle 17 Apr 2022  
51 Computer Graphics in Java and Scala - Part 1b 03 Apr 2022  
52 The Expression Problem Part 2 27 Mar 2022  
53 Computer Graphics in Java and Scala - Part 1 06 Mar 2022  
54 The Expression Problem Part 1 20 Feb 2022  
55 Side by Side - Scala and Java Adaptations of Martin Fowler’s Javascript Refactoring Example 22 Jan 2022  
56 Refactoring: A First Example - Martin Fowler’s First Example of Refactoring, Adapted to Java 16 Jan 2022  
57 Refactoring: A First Example - Martin Fowler’s First Example of Refactoring, Adapted to Scala 31 Dec 2021  
58 ‘go-to’ general-purpose sequential collections - from Java To Scala 28 Nov 2021  
59 The Functional Programming Triad of map, filter and fold 01 Nov 2021  
60 Functional Core and Imperative Shell - Game of Life Example - Haskell and Scala 10 Oct 2021  
61 N-Queens Combinatorial Problem - Polyglot FP for Fun and Profit – Haskell and Scala - Part 4 04 Oct 2021  
62 Quicksort - a whistle-stop tour of the algorithm in five languages and four paradigms 05 Sep 2021  
63 N-Queens Combinatorial Problem - Polyglot FP for Fun and Profit – Haskell and Scala - Part 3 22 Aug 2021  
64 Left and Right Folds - Comparison of a mathematical definition and a programmatic one 08 Aug 2021  
65 N-Queens Combinatorial Problem - Polyglot FP for Fun and Profit – Haskell and Scala - Part 2 01 Aug 2021  
66 N-Queens Combinatorial Problem - Polyglot FP for Fun and Profit – Haskell and Scala - Part 1 04 Jul 2021  
67 Sierpinski Triangle - Polyglot FP for Fun and Profit - Haskell and Scala 15 May 2021  
68 Function Applicative for Great Good of Palindrome Checker Function 04 Jan 2021  
69 Scala 3 enum for a terser Option Monad Algebraic Data Type 06 Dec 2020  
70 Folding Unfolded - Part 5 15 Nov 2020  
71 The Functional Programming Triad of Folding, Scanning and Iteration - A first example in Scala and Haskell 01 Nov 2020  
72 Folding Unfolded - Part 4 11 Oct 2020  
73 The Functional Programming Triad of fold, scan and iterate 10 Oct 2020  
74 Folding Unfolded - Part 3 06 Sep 2020  
75 Folding Unfolded - Part 2 11 Aug 2020  
76 Folding Unfolded - Part 1 04 Aug 2020  
77 Game of Life - Polyglot FP - Haskell and Scala - Part 3 19 Jul 2020  
78 Game of Life - Polyglot FP - Haskell and Scala - Part 2 21 Jun 2020  
79 Game of Life - Polyglot FP - Haskell and Scala - Part 1 25 May 2020  
80 Scala 3 by Example - Algebraic Data Types for Domain Driven Design - Part 2 03 May 2020  
81 From Scala Monadic Effects to Unison Algebraic Effects 13 Apr 2020  
82 Monad Fact #6 29 Mar 2020  
83 Monad Fact #5 22 Mar 2020  
84 Monad Fact #4 14 Mar 2020  
85 Monad Fact #3 01 Mar 2020  
86 Monad Fact #2 23 Feb 2020  
87 Monad Fact #1 16 Feb 2020  
88 The Monad Fact Series 15 Feb 2020  
89 Scala 3 by Example - Algebraic Data Types for Domain Driven Design - Part 1 25 Jan 2020  
90 State Monad 30 Dec 2019  
91 Applicative Functor - Part 3 01 Dec 2019  
92 Applicative Functor - Part 2 17 Nov 2019  
93 Functional Effects - Part 2 20 Oct 2019  
94 Functional Effects - Part 1 06 Oct 2019  
95 Symmetry in the interrelation of flatMap/foldMap/traverse and flatten/fold/sequence 29 Sep 2019  
96 Ad hoc Polymorphism using Type Classes and Cats 21 Sep 2019  
97 Year when lambda functions were introduced in various languages 01 Sep 2019  
98 Function Composition - forward composition versus backward composition 11 Aug 2019  
99 Non-strict functions, bottom, and Scala by-name parameters 21 Jul 2019  
100 Addendum to `Monads do not Compose` 11 May 2019  
101 Monad Transformers - Part 1 19 Apr 2019  
102 Monads do not Compose 14 Apr 2019  
103 Functor Composition 07 Apr 2019  
104 Sequence and Traverse - Part 3 10 Mar 2019  
105 Sequence and Traverse - Part 2 17 Feb 2019  
106 Monoids - Part 2 - With examples using Scalaz and Cats 10 Feb 2019  
107 Monoids - Part 1 - With examples using Scalaz and Cats 02 Jan 2019  
108 Definitions of Functional Programming 02 Dec 2018  
109 Sequence and Traverse - Part 1 28 Oct 2018  
110 Abstracting over Execution with Higher Kinded Types, and how to remain Purely Functional 14 Oct 2018  
111 Applicative Functor - Part 1 22 Sep 2018  
112 Writer Monad for logging execution of functions 02 Sep 2018  
113 Kleisli Composition 15 Aug 2018  
114 Monad Laws Must Be Checked 22 Jul 2018  
115 Point-free or Die - Tacit Programming in Haskell 13 May 2018  
116 Monad as Functor with pair of Natural Transformations 15 Apr 2018  
117 Natural Transformations 01 Apr 2018  
118 Functor Laws 12 Mar 2018  
119 Compositionality and Category Theory 04 Jan 2018  
120 Arrive at monads by going from composition of pure functions to composition of effectful functions 01 Jan 2018  
121 De Morgan's Laws are Monoid Homomorphisms 09 Jul 2017  
122 Lambda Expressions and Java 8 - Lambda Calculus, Lambda Expressions, Syntactic Sugar, First Class Functions 18 Nov 2015  
123 The Open-Closed Principle - Part 2 - The Contemporary Version - An Introduction 15 Oct 2015  
124 The Open-Closed Principle - Part 1 - The Original Version 14 Oct 2015