Nayeem Zen nayeemzen

Purpose

Bootstrap knowledge of LLMs ASAP. With a bias/focus to GPT.

Avoid being a link dump. Try to provide only valuable well tuned information.

Prelude

Neural network links before starting with transformers.

A composable pattern for pure state machines with effects

State machines are everywhere in interactive systems, but they're rarely defined clearly and explicitly. Given some big blob of code including implicit state machines, which transitions are possible and under what conditions? What effects take place on what transitions?

There are existing design patterns for state machines, but all the patterns I've seen complect side effects with the structure of the state machine itself. Instances of these patterns are difficult to test without mocking, and they end up with more dependencies. Worse, the classic patterns compose poorly: hierarchical state machines are typically not straightforward extensions. The functional programming world has solutions, but they don't transpose neatly enough to be broadly usable in mainstream languages.

Here I present a composable pattern for pure state machiness with effects,

Introduction to Kafka

Kafka acts as a kind of write-ahead log (WAL) that records messages to a persistent store (disk) and allows subscribers to read and apply these changes to their own stores in a system appropriate time-frame.

Terminology:

Producers send messages to brokers
Consumers read messages from brokers
Messages are sent to a topic

	CREATE TABLE accounts(
	id serial PRIMARY KEY,
	name VARCHAR(256) NOT NULL
	);

	CREATE TABLE entries(
	id serial PRIMARY KEY,
	description VARCHAR(1024) NOT NULL,
	amount NUMERIC(20, 2) NOT NULL CHECK (amount > 0.0),
	-- Every entry is a credit to one account...