Marcos Benevides mtrsk

Implementing complex numbers and FFT with just datatypes (no floats)

In this article, I'll explain why implementing numbers with just algebraic datatypes is desirable. I'll then talk about common implementations of FFT (Fast Fourier Transform) and why they hide inherent inefficiencies. I'll then show how to implement integers and complex numbers with just algebraic datatypes, in a way that is extremely simple and elegant. I'll conclude by deriving a pure functional implementation of complex FFT with just datatypes, no floats.

A 1000x improvement in performance

We recently had to provide (near) live data to a set of views in our application. After considering the most common ways to build this we decided to go with long polling. Our entire app is event based, so we know if a certain event happed the data might have changed. Lets assume the following types represent what can happen in our application:

type CounterEvent =
  | CounterWasIncremented byValue: int

gpg explained

Plan for today

Brief introduction
Managing keys
gpg key instead of ssh and gpg-agent instead of ssh-agent
hardware tokens

Disclaimer

I’m not a security expert.

I'm trying to follow this guide to install NixOS using Btrfs, LUKS and LVM. The main usage of this page for me will be remembering what I did! My laptop is ASUS ROG GL553VD.

Just downloaded Plasma Desktop, 64bit and create a bootable Flash Drive. Then boot up to NixOS Live CD. Using gparted to create two partitions, One 200MB vfat EFI partittion and the rest of SSD drive will be an encrypted partition.

DISK=/dev/nvme0n1

At the beginning of 2030, I found this essay in my archives. From what I know today, I think it was very insightful at the moment of writing. And I feel it should be published because it can teach us, Rust developers, how to prevent that sad story from happening again.

What killed Haskell, could kill Rust, too

What killed Haskell, could kill Rust, too. Why would I even mention Haskell in this context? Well, Haskell and Rust are deeply related. Not because Rust is Haskell without HKTs. (Some of you know what that means, and the rest of you will wonder for a very long time). Much of the style of Rust is similar in many ways to the style of Haskell. In some sense Rust is a reincarnation of Haskell, with a little bit of C-ish like syntax, a very small amount.

Is Haskell dead?

Haskeller Competency Matrix

See also List of materials about Software Design in Haskell

	Junior	Middle	Senior	Architect
Haskell level	Basic Haskell	Intermediate Haskell	Advanced Haskell	Language-agnostic
Haskell knowledge scope	Learn you a Haskell	Get programming with Haskell	Haskell in Depth	Knows several languages from different categories
	Get programming with Haskell	Haskell in Depth	Functional Design and Architecture
	Soar with Haskell	[Soar

Some recommended books for improving as a software developer

Most software books are too language specific and go out of date too quickly. What I find has stayed with me are books about bigger concepts, such as systems thinking and complexity, and also so-called "soft skills" such as management and psychology.

User experience

These are all really about developing empathy for other people :)

"The Design of Everyday Things" by Donald Norman

	###
	### [2023-06-19] UPDATE: Just tried to use my instructions again on a fresh install and it failed in a number of places.
	###. Not sure if I'll update this gist (though I realise it seems to still have some traffic), but here's a list of
	###. things to watch out for:
	### - Check out the `nix-darwin` instructions, as they have changed.
	### - There's a home manager gotcha https://github.com/nix-community/home-manager/issues/4026
	###

	# I found some good resources but they seem to do a bit too much (maybe from a time when there were more bugs).
	# So here's a minimal Gist which worked for me as an install on a new M1 Pro.

	{ config, pkgs, lib, ... }:

	{
	# This sway config is mostly based on https://nixos.wiki/wiki/Sway
	# which integrates sway with systemd in the style described here
	# https://github.com/swaywm/sway/wiki/Systemd-integration
	# and the replies in https://github.com/NixOS/nixpkgs/issues/57602
	# with some individual packages added/removed and using sddm as the display manager.
	#
	# Take care to start the correct target as described by the sway proejct wiki.

	open System
	open System.IO
	open System.Net
	open System.Text.Json
	open System.Collections.Generic
	open System.Security.Cryptography

	/// Taken from hash.cc in the nix codebase
	/// https://github.com/NixOS/nix/blob/a7540294cfae82c098e8691cd5212a9184add574/src/libutil/hash.cc
	module Base32 =