Things on a Heap

A Collection of Programming Ramblings by chjdev

Task management with my little red book


I’ve been asked what I’m scribbling in my little red book I’m carrying around and thought I’d share. Maybe someone will find it useful.

Docker overrules UFW!

Docker, by default, directly manipulates iptables in order to work its network magic. It thus completely circumvents UFW rules! In this post I show strategies to deal with this.

TLS secured Docker on Ubuntu 16.04 Quickstart


Installing a Vanilla-Docker environment on Ubuntu 16.04 was surprisingly non-straightforward for me. Turns out it would have been actually quite simple, but the docs and tutorials seem to be still assuming 14.04/non-systemd and led me in circles a bit.

HyperLogLog - Big Data™ in your Browser

In this post we’ll take a look at HyperLogLog, a probabilistic data structure that allows you to estimate the cardinality of huge data sets with minuscule memory requirements. This page is running an implementation JavaScript and uses 4kb to estimate a cardinality of up to 10,000,000 unique visitors based on 50,000,000 randomly generated visits.

The k-Means Algorithm Visualized

This quick post started as a challenge to myself: “I wonder if I can bang out a k-means implementation with visualization from memory in less than 2 game of thrones episodes…” The result is an immutable, functional implementation in ES6 including a visualization in D3.js.