Christian Hollinger

Software Engineering, GNU/Linux, Data, ML, and other things

08 Sep 2022

Tiny Telematics: Tracking my truck's location offline with a Raspberry Pi, redis, Kafka, and Flink (Part 2)

7,094 words, ~23 min read

Tracking vehicle location offline with a Raspberry Pi, Part 2: Apache Flink, scala, Kafka, and road-testing.
29 Aug 2022

Tiny Telematics: Tracking my truck's location offline with a Raspberry Pi, redis, Kafka, and Flink (Part 1)

7,395 words, ~24 min read

Building custom Linux images, dealing with a 40 year old GPS standard, & trying to shoehorn functional programming into Python: Tracking vehicle location offline with a Raspberry Pi. (Part 1)
01 Jun 2022

Functional Programming concepts I actually like: A bit of praise for Scala (for once)

6,030 words, ~20 min read

Types, type classes, implicits, tagless-final, effects, and other things: Not everything in the world of functional programming is bleak and overly academic. A view on FP & scala concepts someone who loves to complain actually likes.
27 Feb 2022

Scala, Spark, Books, and Functional Programming: An Essay

7,451 words, ~24 min read

Reviewing 'Essential Scala' and 'Functional Programming Simplified', while explaining why Spark has nothing to do with Scala, and asking why learning Functional Programming is such a pain. A (maybe) productive rant (or an opinionated essay).
03 Dec 2021

Building a Data Lake with Spark and Iceberg at Home to over-complicate shopping for a House

12,270 words, ~40 min read

How I build what is essentially a self-service Data Lake at home to narrow down the search area for a new house, instead of using Zillow like a normal person, using Spark, Iceberg, and Python.
12 Aug 2021

Writing a Telegram Bot to control a Raspberry Pi from afar (to observe Guinea Pigs)

3,388 words, ~11 min read

A quick project to write a Telegram chat bot that can control a camera, connected to a Raspberry Pi, to take pictures of things; or: Why I refuse to trust IoT vendors and do everything myself
03 Jul 2021

Raspberry Pi Gardening: Monitoring a Vegetable Garden using a Raspberry Pi - Part 2: 3D Printing

9,110 words, ~30 min read

Part 2 of throwing Raspberry Pis at the pepper plants in my garden: On the topics of 3D printing, more bad solder jobs, I2C, SPI, Python, go, SQL, and failures in CAD.
25 Apr 2021

Raspberry Pi Gardening: Monitoring a Vegetable Garden using a Raspberry Pi - Part 1

7,051 words, ~23 min read

On how growing vegetables is more complicated than it looks, why bad soldering still works, on moving individual bits around, and what I learned about using technology where one probably does not need technology.
28 Feb 2021

Bad Data and Data Engineering: Dissecting Google Play Music Takeout Data using Beam, go, Python, and SQL

6,706 words, ~22 min read

On the joy of inheriting a rather bad dataset - dissecting ~120GB of terrible Google Takeout data to make it usable, using Dataflow/Beam, go, Python, and SQL.
21 Dec 2020

Why I use Linux

3,624 words, ~12 min read

One question I do get in earnest quite frequently is why I put up with running GNU/Linux distributions for development work. An attempt at a simple response.