Thoughts, stories and ideas

Plex on Docker with IPvlan

Fri, 27 Mar 2026 00:00:00 +0000

Giving Plex one real LAN IP so discovery stops sending clients to dead addresses

Home Assistant blueprint for Logic Group ZDB5100 (and ZBA7140)

Fri, 23 Jan 2026 00:00:00 +0000

A Z-Wave JS blueprint that exposes all 20 scene combinations across the four keys, with placeholders for your automations.

S3 GFS Retention

Mon, 12 Jan 2026 00:00:00 +0000

Keeping S3 backups under control with a GFS retention policy and a tiny Lambda.

One Metric to Rule Them All: Making a Dumb Stove Fan Smart with Only Watts

Fri, 11 Jul 2025 00:00:00 +0000

Using just power usage readings, this Home Assistant automation figures out what your stove fan is doing-and shuts it down when you forget.

Updating ESPHome Devices Sequentially with Home Assistant Scripts

Mon, 12 May 2025 00:00:00 +0000

Avoid overloading your build host by flashing ESPHome devices one‑by‑one, using a pure Home Assistant script that shows progress and waits for running updates to finish.

Smart Refresh Schedule for Sensors in Home Assistant

Fri, 09 May 2025 00:00:00 +0000

Reduce unnecessary sensor refreshes while keeping your local data fresh.

Using dmsetup to Salvage Disks with Bad Blocks

Mon, 07 Apr 2025 00:00:00 +0000

A guide to rescuing disks with bad blocks using dmsetup, avoiding the need for costly replacements.

WLED Backup script

Fri, 28 Mar 2025 00:00:00 +0000

A backup script that discovers WLED instances and backs their configs up

Entity Framework Core: Querying views, but manipulating tables

Thu, 08 Jun 2023 16:43:12 +0000

Exploring techniques for querying from views while inserting/updating through tables in EF Core.

EntityFramework Core – Composite key filtering

Thu, 03 Jun 2021 00:00:00 +0000

Using expression trees to dynamically filter on composite keys in EF Core.

Introducing Elephant Projects - Cross-repository refactoring

Mon, 05 Apr 2021 19:53:27 +0000

A local development tool for switching between NuGet and project references across multiple repositories.

GH Mass-administration: Content

Sun, 28 Mar 2021 17:28:34 +0000

Automating repository content and workflows using JSON metadata and a .NET tool.

GH Mass-administration: Terraform

Sun, 28 Mar 2021 17:28:06 +0000

Using Terraform to configure GitHub repository settings, secrets, and policies at scale.

Consuming NuGet packages from my GitHub

Sun, 28 Mar 2021 10:55:53 +0000

A short guide for consuming GitHub-hosted NuGet packages, using access tokens and CLI.

Mass-administration of GitHub repositories

Sat, 27 Mar 2021 23:10:59 +0000

Overview of templating and managing multiple GitHub repositories with shared configuration and content.

Renaming an index in Elastic (slight hacks)

Fri, 05 Mar 2021 23:27:14 +0000

How to rename an Elasticsearch index via manual state file edits (not recommended in production).

Move WSL to different drive

Wed, 17 Feb 2021 17:42:17 +0000

How to relocate a WSL container to another drive using the export and import commands.

Space Engineers 01.172 - API Documentation

Sat, 05 Aug 2017 12:08:40 +0000

API reference for SE 01.172 with focus on Sandbox.ModAPI scripting interfaces.

Space Engineers, figuring out the API

Sat, 05 Aug 2017 12:06:11 +0000

Tips for exploring and reverse-engineering the Space Engineers scripting API using tools like DotPeek.

Deserializing different types based on properties, with Newtonsoft.Json

Wed, 10 Aug 2016 00:00:00 +0000

Handling polymorphic JSON deserialization with custom JsonConverter in Newtonsoft.Json.

Detecting mismatched objects with Newtonsoft.Json

Wed, 10 Aug 2016 00:00:00 +0000

Catch missing or unexpected JSON fields during deserialization with a custom JsonSerializer setup.

Lets Encrypt organized for reverse nginx proxy

Thu, 07 Jul 2016 10:33:41 +0000

Automating TLS certificate setup and renewal for reverse NGINX proxies using Let's Encrypt.

Bencoding Library–Part two

Fri, 13 Aug 2010 00:00:00 +0000

Previously, I described a Bencoding Library I made to simplify working with the Bencoding structure in .NET. I also published it on Codeplex. However, I discovered a flaw—if a string contains a null-byte (as most .torrent files do), it will fail. So I made a fix, which has been uploaded to Codeplex as changeset 1102.

As can be seen in the changeset, a few files have been changed. Ignoring all the test files, the changes were made to:

LINQ vs. Foreach

Tue, 10 Aug 2010 00:00:00 +0000

I asked around while trying to learn how to use LINQ. LINQ is essentially SQL for .NET—it allows you to query objects directly in memory. For example:

List<int> test = new List<int> { 1, 3, 5 };
List<int> testnew = (from a in test where a == 5 select a).ToList();

Someone claimed LINQ was faster than using foreach for selecting items. So, I tested it.

The Benchmark

static List<int> testlist = new List<int>();

static void Main(string[] args)
{
    DateTime b, a;
    List<double> regularTimes = new List<double>();
    List<double> LINQTimes = new List<double>();

    for (int x = 0; x < 1000000; x++)
        testlist.Add(x * 5);

    // Foreach loop test
    for (int x = 0; x < 1000; x++)
    {
        b = DateTime.Now;
        TestRegular();
        a = DateTime.Now;
        regularTimes.Add((a - b).TotalMilliseconds);
    }
    Console.WriteLine("Regular Avg.: {0}", regularTimes.Average());

    // LINQ test
    for (int x = 0; x < 1000; x++)
    {
        b = DateTime.Now;
        TestLINQ();
        a = DateTime.Now;
        LINQTimes.Add((a - b).TotalMilliseconds);
    }
    Console.WriteLine("LINQ    Avg.: {0}", LINQTimes.Average());

    Console.ReadLine();
}

private static void TestRegular()
{
    List<int> newlist = new List<int>();
    foreach (int item in testlist)
        if (item % 2000 == 0) newlist.Add(item);
}

private static void TestLINQ()
{
    var newlist = (from a in testlist where a % 2000 == 0 select a).ToList();
}

This runs each selection method 1000 times on a list of 1,000,000 items.

PDF Search Site

Tue, 10 Aug 2010 00:00:00 +0000

An Introduction

So, I’m moving into an apartment in the near future. Following that, I will have to learn how to manage my documents and ensure I can find them back in time. I’ve thought of a few solutions, one of them being what I do now – where I simply have a folder with PDFs of my documents (I digitalize everything). This works fine now… (I have like … 20 documents)… But it may not work in 2 years when I have a hundred documents spread over many different corporations and years.

Bencoding – A C# Library

Mon, 09 Aug 2010 00:00:00 +0000

I’ve long wanted to write a Bencoding library. Bencoding is an encoding format for encoding objects like text, lists, dictionaries, etc., into a single piece of text. It’s often used for transporting configuration files.

Bencoding is most famous for its use in the Bittorrent protocol—it forms the basis for .torrent files. I wanted to create a C# library to support all known Bencoding object types. You can read more about the encoding here.

Wardriving – The triangulation algorithm

Sat, 07 Aug 2010 00:00:00 +0000

Introduction

For my previous post, where I find the signal strength of WiFi spots, I also needed an algorithm to actually locate the spot. I decided to use triangulation, which is commonly used in wireless communications to locate devices based on signal strength from known positions.

As my system uses GPS, I had to consider the Earth’s curvature. Calculating the geographic midpoint on a sphere isn’t trivial, but GeoMidpoint provides a great explanation (Method A).

C# Wifi Scanner

Thu, 05 Aug 2010 00:00:00 +0000

Introduction

I’ve long wanted to build a WiFi-based application—ideally one that also records GPS location data for wardriving. I searched for manageable C# solutions integrated with .NET.

First Attempts

I explored many WMI tutorials, but on Windows 7, I lacked the needed namespaces like MSNdis_80211_ServiceSetIdentifier.

Eventually, I discovered the WLan API (available since Windows XP SP3), usable via P/Invoke. Fortunately, someone made a ManagedWifi wrapper for it—perfect!

The Scanner

I wrote a small utility that scans for SSIDs across all interfaces and retrieves their MAC addresses.

Danish CPR Numbers

Tue, 03 Aug 2010 00:00:00 +0000

I was reading several articles about the new NemID system in Denmark, and concerns around how organized groups might generate valid CPR numbers and brute-force passwords. This could lead to account lockouts—potentially paralyzing major parts of the country’s digital infrastructure.

To test this, I created code to generate valid CPR numbers based on known rules.

The Rules

The original rules were based on a textbook I no longer have, but I found newer ones via this blog post, official article, and PDF document from the CPR register.

Mobifinance – Loaning organized

Sun, 01 Aug 2010 00:00:00 +0000

Idea

While on a trip to Jutland, I had a splendid idea: a system to track loans—who I loaned money to and whether I ever got it back. It had to work on mobile devices and as a web app, so I built it as a small webpage.

I used an MSSQL database (hosted by addnet.dk) and wrote the app in C#.

Database

I built a single main table, Finances, for all loans and edits. Each finance can have a parent—NULL indicates a root loan. This allows loan tracking and later edits. A root loan of +10 DKK, followed by a -10 DKK update, resolves to 0 (paid).

Linux incremental hardlink backup system

Thu, 29 Jul 2010 00:00:00 +0000

Introduction

While reviewing my old college’s IT class backup system (due to running low on disk space), I discovered a major flaw: a weekly 1:1 backup of every user’s files—about 40 GB per week. Many of these files never change. Ever.

Solution: Incremental backups.

I challenged myself to code an incremental backup system using only Python and the Linux extfs filesystem.

The Scenario

At my former college, students ran the IT department. They set up a system with a 2 TB drive (two 1 TB disks) that made weekly full backups of every user, including alumni.

SMS System

Thu, 29 Jul 2010 00:00:00 +0000

Introduction

As part of the OEP platform at my previous college, we designed an SMS subsystem for messaging Danish mobile phones. It was intended for alerts like account lockouts or password resets. I coded it in Python.

The Scenario

We used LDAP as a central user database. The script needed to accept either a phone number or username, then look up the mobile number via LDAP (mobile attribute). I used python-ldap for this, available via Ubuntu’s package system.