Greg Helton greghelton

A backgammon game with a trained AI opponent.

Here's what has been built:

BackgammonEngine — a complete Swift game engine with legal move generation, all backgammon rules, and the TD(λ) neural network
BackgammonTrainer — a self-play training harness that ran 500,000 episodes in under 50 minutes on your M4 Macbook Pro
BackgammonApp — a SwiftUI iPhone game where you play against the trained AI

Set which developer toolchain runs by default.

I'm using the Calva extension in IntelliJ IDEA and sometimes I run the game from the REPL.

(play-until-winner initial-game-state)

Sometimes I run it from the bash command line.

java -cp "lib/spec.alpha-0.6.249.jar:lib/core.specs.alpha-0.5.81.jar:lib/clojure-1.12.0.jar:src/main/clojure" clojure.main -i src/main/clojure/backgammon/core.clj -e "(in-ns 'backgammon.core)" -e "(play-until-winner initial-game-state)"

Install emacs on a Mac
Commands Run:
brew install emacs
/opt/homebrew/opt/emacs/bin/emacs --fg-daemon
open new terminal tab
emacsclient -c

Using emacs
Note that on the Mac keyboard, Meta is ⌥ and Control is ^

Whenever I write some code to deal with data about people then functional programming seems to work best. Whenever I write some code to simulate people then object-oriented programming seems to work best.
— Michael Fogus

Object oriented programming makes code understandable by encapsulating moving parts. Functional programming makes code understandable by minimizing moving parts.
— Michael Feathers

• A function doesn’t have to be 100% pure to get many of the benefits of purity.
• Of course you don’t want to use the fact that it’s not 100% pure as an excuse for making it even less pure.
• A more functional programming style often results in more parameters to a function.
• A functional style does lead to more parameters but, it is much easier to test the functions in isolation.

% docker run --platform linux/amd64 -e "ACCEPT_EULA=Y" -e "SA_PASSWORD=your-password"
-p 1433:1433 --name sqlserver -d mcr.microsoft.com/mssql/server:2022-latest

% docker ps

% brew install --no-quarantine mssql-tools

% sqlcmd -S localhost -U sa -P 'your-password'

The Lost Decades

A friend claims that software design evolved as an engineering disipline due to the move from waterfall SDLC (systems development lifecycle) to the agile project management process. He claims that the move from waterfall SDLC to agile methodology is what propelled application design from monolithic style applications to modular code that works with unit testing frameworks.

The first reference to SDLC dates to a 1968 software conference (https://en.wikipedia.org/wiki/NATO_Software_Engineering_Conferences) and ironically, waterfall SDLC was not proposed as a methodology that would succeed but rather it was presented as the antithesis of a workable methodology. His thesis is that methodology impacted the design of application code, pushing it from monolithic to modular. I too am interested in how the style of application code evolved from monolithic programs to modular code. Was it a top down movement driven by methodology or did programmers develop new goals for the code they wrote, going

	(ns backgammon.ai
	"TD-Gammon inspired reinforcement learning AI for backgammon.

	Architecture:
	- Neural network: input(198) → hidden(40) → output(1)
	- Input: Tesauro's 198-feature encoding of board state
	- Output: estimated probability that White wins
	- Training: TD(λ) temporal difference learning
	- Eligibility traces for credit assignment across moves

	(ns my-project.core
	(:require [clojure.spec.alpha :as s]))

	;; Define a simple spec for a 'User' map
	(s/def ::name string?)
	(s/def ::age int?)
	(s/def ::user (s/keys :req [::name ::age]))

	(defn -main [& args]
	(let [valid-data {::name "Greg" ::age 30}

	import com.ibm.arithmetic.decimal.DecimalPrecision;
	import com.ibm.arithmetic.decimal.daa.DAAVariable;
	import com.ibm.arithmetic.decimal.daa.DAAPrecision;
	import com.ibm.arithmetic.decimal.daa.DAAFactory;
	import com.ibm.arithmetic.decimal.daa.DAADecimal;
	import com.ibm.arithmetic.decimal.edit.Formatter;

	public class TestInterestExample {
	private static final DAAFactory df = DAAFactory.INSTANCE;

	Install homebrew per the instructions here: https://brew.sh/

	brew install --cask temurin

	brew install --cask intellij-idea-ce

	brew install maven

	brew install kotlin