jonjack

BTC 5 minute market Chainlink migration to TWAP 60

Overview

In August 2026, Polymarket updated the Chainlink BTC/USD price feed for the 5 minute market such that it is no longer the real-time price feed but rather a Time-weighted Average Price (TWAP) calculated from the previous 60 seconds of data. The reason was that market manipulators were able to move the real-time BTC price in the last seconds of the market in order to manipulate the Polymarket 5 minute markets. By shifting the feed to the TWAP 60 this makes it more difficult to manipulate the market because the resolution price (the market end price) is based on an average of the last 60 seconds of the market so manipulators would have to use a lot of capital to move the price over 60 seconds.

• Spot price - this is the previous Chainlink oracle BTC/USD price.
• TWAP 60 - this is the new Chainlink feed used in the 5 minut

jonjack

macOS Install NVM & Node

This guide assumes a clean install. If you have Node already uninstalled then remove it first.

Install NVM

You can install NVM with brew but it isn't fully supported so go with the official instructions for piece of mind.

curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.40.1/install.sh | bash

jonjack

Rust Guide

A summary of my Rust learnings largely guided by reading the offical Rust guides:-

The Rust Programming Language
The Rust Language Reference
Rust by Practise

jonjack

String:

                  buffer
                 /   capacity
                /   /   length
               /   /   /
            +–––+–––+–––+
stack frame │ • │ 8 │ 6 │ <- my_string: String
            +–│–+–––+–––+
              │

jonjack

By default, CloudFront distribution URLs (eg. https://d2kl2vxl3xne45.cloudfront.net) are publicly accessible. So if you are using CloudFront to serve a static website out of S3, for example, then your site shall also be accessible via the CF URL as well as any custom domain you are using. If you are using Signed URLs or Signed Cookies to restrict access to your content then this is not an issue, but if you are serving your content publicly then it might bother you.

I am not sure if CloudFront URLs are easily discoverable (probably not) but if we want to ensure that our web application cannot be accessed via the CF URL then we need to block access to it.

AWS Docs Tutorial: Create a simple function with CloudFront Functions

WAF - an alternative solution may be to use AWS WAF custom rules (assuming you are using WAF that is). You would also only probably want to explore this option if you are using WAF at the C

jonjack

Glossary

An evolving glossary of terms used in functional programming, mathematics and computing in general.

An understanding of many mathematical terms is fundamental to get an understanding of many of the principles embodied in functional programming.

A few other glossaries that may come in handy:-

Reactive Manifesto
Programming in Scala

jonjack

jonjack

#!/usr/bin/env zsh

git show-branch -a \
| grep '\*' \
| grep -v `git rev-parse --abbrev-ref HEAD` \
| head -n1 \
| sed 's/.*\[\(.*\)\].*/\1/' \
| sed 's/[\^~].*//'

jonjack

Program: Visual Studio Code
Extension: Code Runner 0.9.10 (code-runner-0.9.10)
Problem: When attempting to run a script/program, VS Code reports error: "command 'code-runner.run'"
Fix: Manually edit extension code.

Edit extension file codeManager.js
On macOS this is usually at ~/.vscode/extensions/formulahendry.code-runner-0.9.10/out/src/codeManager.js

Comment out line 12.

jonjack

cask "mysqlworkbench-8.0.22" do
  version "8.0.22"
  sha256 "4e27de82d869043cf80e803f1a57cc041a91cabddf0aa6a6c054d68af1837d48"
  url "https://downloads.mysql.com/archives/get/p/#{version.major}/file/mysql-workbench-community-#{version}-macos-x86_64.dmg"

  name "MySQL Workbench"
  desc "Visual tool to design, develop and administer MySQL servers"
  homepage "https://www.mysql.com/products/workbench/"

  app "MySQLWorkbench.app"