Julik Tarkhanov julik

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It's just the beginning

julik / musherator.rb

Created March 11, 2025 12:39

julik / replicate.html

Created February 22, 2025 19:50

	<!DOCTYPE html>
	<html>
	<head>
	<style>
	.outlinerounded {
	width: 1px; height: 1px; overflow: hidden; border: 1px solid gray;
	}
	</style>
	</head>
	<body>

julik / rae.rb

Created February 13, 2025 01:04

AES encryption with random access to plaintext (playground)

	require "openssl"
	require "stringio"

	class PassthruScheme
	READ_OR_WRITE_CHUNK_SIZE = 1 << 16

	def streaming_encrypt(from_plaintext_io, into_ciphertext_io)
	while (chunk = from_plaintext_io.read(READ_OR_WRITE_CHUNK_SIZE))
	into_ciphertext_io.write(chunk)
	end

julik / substreams.rb

Created February 7, 2025 16:32

AES-CFB with substream-based blocks

	# frozen_string_literal: true

	require "test_helper"

	class BlockwiseEncryptionTest < ActiveSupport::TestCase
	class NonRandomAccessible
	def initialize(encryption_key)
	@algo = "aes-256-cfb"
	@iv_and_key_length = 16 + 32
	@key_derivation_salt = "my desire"

julik / deploy.sh

Created April 30, 2024 08:31

The Deployinator™©

	#!/usr/bin/env bash

	set -e

	# This script will build a Docker image from the current state of the working tree.
	# It will tag it with the short Git sha, and then push it to Quay.io under our company
	# account. Afterwards the image can be picked up from other hosts to deploy.

	export DEPLOY_HOST=<someapp>.<my-domain>
	export REV=`git log -1 --pretty=%h`

julik / streaming_controller.rb

Created February 24, 2024 01:47

	class StreamingController < ApplicationController
	class Writer
	def initialize(&blk)
	@blk = blk
	end

	def write(stuff)
	@blk.call(stuff)
	stuff.bytesize
	end

julik / pecobox.rb

Created February 9, 2024 14:59

A circuit breaker using Pecorino leaky buckets

	# frozen_string_literal: true

	# Pecobox is a Circuitbox-like class which uses Pecorino for
	# measurement error rates. It is less resilient than Circuitbox
	# because your error stats are stored in the database, but guess what:
	# if your database is down your product is already down, so there is
	# nothing to circuit-protect. And having a shared data store for
	# the circuits allows us to track across machines and processes, so
	# we do not have to have every worker hammer at an already failing
	# resource right after start

julik / localities.sql

Created June 4, 2023 10:23

Versioned table with grouping by updated_at

	CREATE TABLE localities (
	id uuid DEFAULT gen_random_uuid() PRIMARY KEY,
	source_updated_at TIMESTAMP,
	name TEXT
	);
	INSERT INTO localities (name, source_updated_at) VALUES
	('London', '2023-04-01'),
	('London', '2023-03-15'),
	('Paris', '2023-02-11'),
	('Canberra', '2022-10-05');

julik / postgres_prorate_leaky_bucket.rb

Last active August 28, 2022 08:25

	# This offers just the leaky bucket implementation with fill control, but without the timed lock.
	# It does not raise any exceptions, it just tracks the state of a leaky bucket in Postgres.
	#
	# Leak rate is specified directly in tokens per second, instead of specifying the block period.
	# The bucket level is stored and returned as a Float which allows for finer-grained measurement,
	# but more importantly - makes testing from the outside easier.
	#
	# Note that this implementation has a peculiar property: the bucket is only "full" once it overflows.
	# Due to a leak rate just a few microseconds after that moment the bucket is no longer going to be full
	# anymore as it will have leaked some tokens by then. This means that the information about whether a

julik / mft_workbench_tabletop_calculator.rb

Last active September 16, 2021 13:40

	mft_gap_mm = 96
	offset_outer_mm = 70 # (mft_gap_mm / 2)
	# Long side needs an odd number of gaps so that the center span of the
	# workbench ends up between two rows of holes and never overlaps the holes
	1.step(22,2) do \|n_gaps_x\|
	1.upto(10) do \|n_gaps_y\|
	width_mm = (offset_outer_mm * 2) + (mft_gap_mm * n_gaps_x)
	height_mm = (offset_outer_mm * 2) + (mft_gap_mm * n_gaps_y)
	puts "#{width_mm}x#{height_mm}mm with #{n_gaps_x + 1} holes along and #{n_gaps_y + 1} holes across"
	end