chris-belcher

Design for a CoinSwap Implementation for Massively Improving Bitcoin Privacy and Fungibility

25/5/2020

Abstract

Imagine a future where a user Alice has bitcoins and wants to send them with maximal privacy, so she creates a special kind of transaction. For anyone looking at the blockchain her transaction appears completely normal with her coins seemingly going from address A to address B. But in reality her coins end up in address Z which is entirely unconnected to either A or B.

Now imagine another user, Carol, who isn't too bothered by privacy and sends her bitcoin using a regular wallet which exists today. But because Carol's transaction looks exactly the same as Alice's, anybody analyzing the blockchain must now deal with the possibility that Carol's transaction actually sent her coins to a totally unconnected address. So Carol's privacy is improved even though she didn't change her behaviour, and perhaps had never even heard of this software.

bradwestfall

S3 Static Sites

⚠ This post is fairly old. I don't keep it up to date. Be sure to see comments where some people have posted updates

What this will cover

• Host a static website at S3
• Redirect www.website.com to website.com
• Website can be an SPA (requiring all requests to return index.html)
• Free AWS SSL certs
• Deployment with CDN invalidation

kennethreitz

#!/usr/bin/env python
# -*- coding: utf-8 -*-

import urllib2

gh_url = 'https://api.github.com'

req = urllib2.Request(gh_url)

password_manager = urllib2.HTTPPasswordMgrWithDefaultRealm()

sbarratt

import argparse
import requests

def get_allocation(address, blockchain):
    id = {
      "sol": 1,
      "eth": 2,
      "sui": 21,
      "aptos": 22,
      "inj": 19,

hofmannsven

Raspberry Pi

• Related tutorial: http://raspberrypiguide.de/
• Command Line Cheatsheet: https://gist.github.com/hofmannsven/8392477

Setup

Find all available devices arp -a

Locate Raspberry (b8:27:eb) in Network: Pi Finder

SSH

skuttruf

"""
Python code for fractional differencing of pandas time series
illustrating the concepts of the article "Preserving Memory in Stationary Time Series" 
by Simon Kuttruf

While this code is dedicated to the public domain for use without permission, the author disclaims any liability in connection with the use of this code.
"""

import numpy as np 
import pandas as pd

yutelin

import Foundation
import CryptoSwift

extension String {
 
    func aesEncrypt(key: String, iv: String) throws -> String{
        let data = self.dataUsingEncoding(NSUTF8StringEncoding)
        let enc = try AES(key: key, iv: iv, blockMode:.CBC).encrypt(data!.arrayOfBytes(), padding: PKCS7())
        let encData = NSData(bytes: enc, length: Int(enc.count))
        let base64String: String = encData.base64EncodedStringWithOptions(NSDataBase64EncodingOptions(rawValue: 0));

dschep

Installing Python 3.6 on Raspbian

As of January 2018, Raspbian does not yet include the latest Python release, Python 3.6. This means we will have to build it ourselves, and here is how to do it. There is also an ansible role attached that automates it all for you.

1. Install the required build-tools (some might already be installed on your system).

timrijckaert

Firebase Topic Counter

This little script will output the amount of tokens subscribed to a topic.
You will need to replace the variables with your personal ones in order for it to work.

We used this function in a Lambda which sends the results to a monitoring dashboard.

How to get the variables

Screenshots in the comments.

• Go to the Firebase Console.

mayoff

#import <UIKit/UIKit.h>
#import <ImageIO/ImageIO.h>
#import <MobileCoreServices/MobileCoreServices.h>

static UIImage *frameImage(CGSize size, CGFloat radians) {
    UIGraphicsBeginImageContextWithOptions(size, YES, 1); {
        [[UIColor whiteColor] setFill];
        UIRectFill(CGRectInfinite);
        CGContextRef gc = UIGraphicsGetCurrentContext();
        CGContextTranslateCTM(gc, size.width / 2, size.height / 2);