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Monthly Meanderings: August 2026

2026-09-01T00:00:00Z

Another month, another edition of “What’s Chris been up to?”. Fun fact: I very nearly published this post with a “[intro]” placeholder here instead of this paragraph, despite proofreading it multiple times. “Yep, that’s where the intro will go, all good”. Now instead we have this weirdly meta introduction.

Website updates and other projects

A few website updates this month, and one of them neatly addresses the “other projects” bit too. First, I’ve added a new fitness page which has some stats and information about my cycling and running. I’ve also added some fitness-related widgets to support that page and these monthly summaries, and a new music one you can see a bit further down.

I’ve also added what I think is quite a fun new feature: a post feed builder that lets you build RSS feeds containing only posts that are semantically similar (or dissimilar) to other posts. So if you want to only hear about my fitness journey you can pin a few of those posts, or if you want to exclude posts that talk about LLMs you can exclude a few of those. It’s basically super-charged fuzzy tags, but it means I don’t have to actually tag things.

I blogged about building a family of single-user services which is where most of my coding energy went this month. Those projects were almost entirely authored by LLMs, and I’m not hating the process. The models have got a lot better at coding, and I enjoyed getting to focus on the bigger picture aspects rather than getting bogged down in details. Rest assured, all the writing on my website is still 100% me. I am the load-bearing seam, here.

Entertainment

Back in March I said ‘I can’t do “what I listened to last month” stats until next month’, and then for the next four months completely forgot about it. Well, not any more! Now I come equipped with some stats about my monthly music habits:

	Album	Artist	Unique tracks played	Total tracks played
1	Fallen	Evanescence	8	40
2	Love, Drugs & Misery	Eva Under Fire	12	32
3	NEON VOID	Sumo Cyco	6	23
4	The Strange Case of…	Halestorm	11	21
5	Coming in Hot	DIAMANTE	9	20
6	Everest	Halestorm	7	20
7	Glory Days	Little Mix	5	20
8	From Zero	Linkin Park	9	19
9	KPop Demon Hunters (Soundtrack from the Netflix Film)	KPop Demon Hunters Cast	7	19
10	No Need to Argue	The Cranberries	6	19

I suspect I won’t show this every month, as it’s probably going to be quite same-y. I, shockingly, tend to play music that I like more than that which I don’t. I’ll usually either put on my “favourites” playlist, or my “daily mix” playlist which biases higher-rated tracks over lower ones. So effectively this just becomes a noisy view over how highly I’ve rated the tracks in an album. Maybe I can control for that, but then I’m not sure what it’d actually be showing… “Here are all the albums I played this month that I don’t usually play because I don’t like them as much as the other albums I’m not showing any more”? It’s a bit wordy. Back to the drawing board with that idea, I think.

I was away for a few weeks this month, including a few days at a small LAN event. Being at a computer gaming event meant that we, naturally, played some board games. Apparently I hit an h-index of 23 from these plays. That’s 23 games I’ve played at least 23 times each. I’ve been at 22 since December last year: obviously the higher the number goes, the harder it is to reach. I also go on and off games (and the whole hobby at times), which doesn’t help on that front. Anyway, here’s ~~Wonderwall~~ the plays for this month:

6 plays
3 plays
3 plays
1 play
1 play

No films this month, but my World of Warcraft habit has picked back up with the launch of the new season. They’ve made Mistweaver Monk, my previous specialisation, a lot less fun to play, so I’m focusing on one of my many alts: a Restoration Shaman:

Level 90

Female Dwarf

Restoration Shaman

309 average item level

Hirameth-Terenas

Professions

Midnight Blacksmithing		41/100
Midnight Inscription		72/100
Midnight Fishing		35/300

Mythic+

Altar of Fangs	+10	23:10	329
Den of Nalorakk	+10	27:36	325
Kings' Rest	+12	28:57	370
Murder Row	+12	28:37	371
Ruby Life Pools	+11	24:28	340
Temple of Sethraliss	+10	30:57	321
The Blinding Vale	+10	24:38	327
Voidscar Arena	+10	22:37	329
Total M+ rating	2711

View on blizzard.com View on raider.io

I don’t quite like it as much as Mistweaver in season 1, but it’s a lot nicer than Mistweaver in season 2. You can actually make health bars move when you press your healing buttons, rather than ignoring half of them because they’re not worth using.

Fitness

My running kick is still going. I’ve “officially” finished the couch-to-5k programme I was doing, and I actually hit 5k on the last day of the programme. I didn’t actually mean to do that: I was saving the 5k run for this week, but by the time I noticed I’d run “too far” it was close enough that I just kept going. I have an actual 5k race coming up this month, which is exciting. Once that’s over I’m planning to work my way up to 10k. I’ve added a few widgets to keep track of some stats:

activities

6h 5m

total time

103.6km

total distance

42.3km

longest distance

🏆️ New PB 1km 2:17 1:52
🏆️ New PB 2km 5:34 4:13
🏆️ New PB 5km 14:51 12:32
🏆️ New PB 10km 36:00 27:21
🏆️ New PB 20km 1:43:33 1:13:24
🏆️ New PB 30km no previous 1:54:25
🏆️ New PB 40km no previous 2:55:52

activities

6h 16m

total time

43.1km

total distance

5km

longest distance

🏆️ New PB 800m 5:56 6:02
🏆️ New PB 1km 7:35 7:36
🏆️ New PB 1 mile 12:28 12:16
🏆️ New PB 2km 15:35 15:16
🏆️ New PB 3km 24:32 23:05
🏆️ New PB 5km no previous 38:40

As well as the running, I did a couple of long (for me) cycle rides, clocking in at around 40 km. It’s a fun loop, but both times I did it I started flagging towards the end. The second time I made sure to eat and drink plenty along the way, and my legs still raised objections about halfway round. My next goal is 50 km which would let me get to the next town over and back but the route has a lot more elevation to go with its increased length, so it’s probably going to be quite a bit more taxing. I’m not sure when I’ll attempt that, as the weather is starting to turn. I was previously bemused when people mentioned “cycling seasons” and switching to indoor trainers. Then I wanted to go out when it was raining, and suddenly I understood. Running in the rain: surprisingly pleasant; cycling in the rain: no thank you.

Around the web

Hacker News In Uncompromised Detail

When I first read the title my gut reaction was “I know everything I need to know about Hacker News, right?”. The title is accurate though. There’s so much interesting stuff, presented really cleanly. It’s a good read.

A proposal for new Netflix content rating icons

Another dry sounding title, another fun article. It starts with a treatise on rating systems and ends with a lovely satirical list of rating ideas.

Find Git commits by commit message text

I like to think I’m relatively well versed in how to use Git. I can do an interactive rebase and everything! This tip from Ham was new to me, though, and is incredibly useful.

Novice Marathon Training Plan

Hal Higdon has a whole bunch of training plans. He literally wrote the book on marathon training. I’ll hopefully be following this plan next year, assuming I manage the 5k, 10k and half-marathon training! This would be the perfect plan for someone who’s run a half marathon a while ago, and is tempted to join me in my “marathon before I’m 40” goal…

Monthly Meanderings: March 2026

2026-04-01T00:00:00Z

Since last month’s update I’ve been unpleasantly reminded that I’m middle aged, through the medium of a dodgy knee. There’s nothing quite like not being able to stand up without groaning to underscore that you’re not young any more. The ongoing game of “will this seemingly mundane activity make my knee go funny again?” is a delight to play, too. I’m great at it.

Website updates

Two new blog posts this month: the longest way to represent a date is a short thought experiment on absurd date formats, and modern CSS is fun goes through some neat new CSS features I’ve used recently for this site.

I did some design tweaks this month: headers now have a blue background behind them¹, and a lot of components have been redesigned to have a consistent style. You can see that component in action in the new “now playing” widget I’ve added:

Black Eyed Peas — My Humps Monkey Business Scrobbled 3m ago

Instead of each component defining its own styles (which were mostly copied and pasted), there’s now a single class that handles the drop shadow, border, background colour, and the optional title. It also applies a consistent format to elements that are clickable: they use the blue accent colour for their borders, and have a glow effect shown on hover.

The now playing widget is part of a larger bit of work I did on importing some music stats. I’m pulling in the data from my Navidrome instance. A new music page shows my most listened albums and artists. Navidrome doesn’t store a complete play history, just the last play and the count, so I can’t do “what I listened to last month” stats until next month.

Other projects

Other than a minor bug-fix update to contempt, my Dockerfile templating/updating tool, I’ve not done much on my other open source projects. I’ve got a bit more work to do finish migrating all my repositories from GitHub to my private Forgejo instance. I’ve also been thinking about mirroring my public repositories to Codeberg so there’s a non-GitHub way to access them.

Entertainment

I apparently only watched a single film in March:

The Substance

2026-03-18

I really didn’t get on with this. It’s too long for what it is, and over-the-top in a way that just didn’t work for me.

Demi Moore and Margaret Qualley were great, but nothing else really was. The cinematography and sound design were too affected, the plot was pretty shallow and obvious, most of the body horror fell into the uncanny CGI valley for me.

It’s not completely without merit: there were around 40 minutes in the middle where I was really into it, but that’s not really enough given it’s closing in on a 2.5 hour runtime.

There’s something to be said for the message it’s presenting about women in Hollywood, too, but it was very heavy handed. Dennis Quaid’s character is even called Harvey; it’s not so much a subtle nod as a sledgehammer to the face.

Instead of films, I’ve been watching a bunch of TV. After devouring The Pitt last month, I struggled to find something to fill the hole it left. I settled on catching up on Chicago Fire and Chicago P.D.. They’re both mostly about getting things done without personal drama becoming the primary focus. They’re not quite as grounded as The Pitt, but at least they’ve not completely gone off the deep end like 9-1-1 where the first responders end up in space somehow?

I’ve also watched the first two episodes of SNL UK. I didn’t have very high expectations, and it gave me a pleasant surprise. Both episodes so far have some hilarious sketches, and are obviously written by British comics with the typical darker, more sardonic humour that separates us from the USA.

Last but not least, board games! I spent a weekend at a tabletop/LAN event with friends, so got to physically play some games for a change. I also kept up with some turn-based games on Board Game Arena, as usual.

6 plays
4 plays
4 plays
4 plays
3 plays
3 plays
3 plays
2 plays
2 plays
2 plays
2 plays
2 plays
1 play

Around the web

Warranty Void if Regenerated

Some really cool speculative fiction about a future where all software is written by LLMs, and the social effects that may have. Unfortunately the story itself is written with an LLM, and that becomes painfully obvious about a third of the way in. By that point I was already hooked, though.

My 2-step process for AI-free blogging

Speaking of LLM-generated text, this short piece by Manuel Moreale made me laugh. I’m by no means anti-LLM, but I really hate people publishing the output like it’s their own work. It breaks the social assumption that the writer put more effort in than the reader, and makes me wonder how much is hallucinated.

25 Years of Eggs

An interesting applied use of coding agents. I’m a sucker for personal statistics. I have no explicit desire to keep my receipts, or generate graphs of my egg consumption, but seeing the graphs makes me question that. The journey to get there is a great read, too.

I made a one-page notebook

The clever paper folding is interesting, but I really like some of the small touches on the page. There’s a nice little “in reply to” callout providing context at the top of the page, you can click to rotate the image further down, and there’s a details element containing a textual version of it. It has that great ‘small web’ vibe of someone who really cares about what they’re doing.

Workers who love ‘synergizing paradigms’ might be bad at their jobs

I haven’t read the full paper, but the summary given by the article is equal parts interesting and amusing. They developed a “Corporate Bullshit Receptivity Scale”, what more is there to say?

It’s meant to resemble painter’s tape, but I’m not sure quite how well it works. ↩︎

Further Adventures in Music Organisation

2025-09-21T00:00:00Z

I wrote before about how I’d dropped Spotify in favour of locally stored music, but things have advanced a bit since. I had a few issues: Tauon would occasionally manage to lose its database and along with it all my carefully constructed playlists and song ratings¹, and the experience on my phone was not very fun.

I had to manually sync the music by plugging my phone in to the computer, and sometimes it just refused to mount the right partition. I don’t think there’s really a good way to debug an Apple phone not behaving properly when connected to a Linux desktop. Then I started wanting more than one playlist synced², and trying to find a way to make that work just broke me.

I spent a while looking at different ways of hosting the music centrally. Plexamp gets lots of good reviews, and I’ve used Plex a fair bit. I set about spinning up a Plex server, and just could not get it working. The server ran fine, served the web interface, but would neither associate with my account nor run standalone. The docs were contradictory and there was very little useful logging. After a lot of frustration, I stumbled across mentions that Plex block running on Hetzner. I assume that’s the cause of my issues, although I have no way to know for sure. I use Hetzner for all my servers and other hosted services, but Plex have decided I can’t run the self-hosted software that I have a lifetime subscription for there. What the actual fuck?

I could have probably worked around the arbitrary restriction, but I didn’t want to throw more time down the drain. Instead, I set up Navidrome, an open source music server. It supports the Subsonic protocol, which means you can use a whole slew of different clients with it (or even write your own). It also means there’s a nice way to get data in and out of it programmatically, which I recall being a bit of a fight with Plex.

Syncing and organising

All my music lived on my desktop, but now I wanted it on my server. At first I just used rsync to copy everything up. I’d maintain a local “master” copy, and periodically shove the changes to the server³. That quickly got old, so I set up Syncthing to keep the two folders in sync. That worked… for a while.

Concurrently, I was looking at improving the organisation of my music. It was mostly organised by some Go programs I’d thrown together to automate the importing, with no real validation of metadata or anything else. Some albums got split up into multiple folders because the tracks had different artists (and didn’t have an album artist set); some artists ended up with multiple folders with slight spelling or case variations. It was upsetting.

I’d used MusicBrainz Picard before to fix some issues, but I didn’t really like the UI, especially when trying to do bulk actions. The main alternative is beets, which describes itself as “the music geek’s media organiser”, and is entirely command line. I was intrigued.

I started playing around with beets, and quickly noticed a problem. Every time I changed a metadata tag in a music file, Syncthing had to upload the entire file. I was frequently changing tags across the whole library as I got beets set up how I wanted, and Syncthing was handling it by uploading gigabytes of files for every minor change. I was already a bit unhappy with having the content duplicated in two places, so now I was using a command line organiser I figured I could just get rid of my local copy and move everything to the server.

I set up a Docker container for beets, and then wrote some incredibly hacky shell scripts so I could run beet locally on my desktop and it would SSH to the server over Tailscale and exec into the container, passing the arguments along. Then I did one final sync of the music library, got rid of Syncthing, double checked I had a backup and deleted all of my local music.

Bears, Beets, Battlestar Galactica

Beets is amazing. It has a vast array of plugins that can do almost anything you could want with a music library, and the command line workflow works really well for me. It’s very well documented, and all the individual parts are pleasingly simple and easy to understand.

Here’s what it looks like when importing some new music:

Beets importing an album

If it doesn’t get a perfect match then it shows the closest matches, and summarises what’s different about them (missing tracks, different names, etc), and lets you decide what to do. Aside from the metadata matching, it’s doing a lot of things under the hood that aren’t necessarily apparent. It:

Looks up the genre from Last.fm
Analyses all the tracks and writes ReplayGain metadata to them
Fetches album art
Checks all the files to make sure they’re actually playable
Scrubs any existing metadata tags

It also maintains its own database, and you can query against it. The query language is both simple and quite powerful, like the rest of beets. As an example:

$ beet ls artist:"Linkin Park" year:2025 length:2:00..2:30 
Linkin Park - From Zero - Casualty

Almost all the other commands also let you use the query syntax, which makes the whole tool really powerful. Want to delete all country tracks that you added last month? No problem. Redownload all the album art for a certain band? Easy. You can even do smart playlists using the filters.

Actually playing music

With all this organisation, I’ve not actually mentioned one tiny detail: how I actually play music now. Navidrome has a web UI, which is perfectly usable, but I don’t really want my web browser involved as it makes balancing sound levels tricky, and getting media keys working is a pain. Thankfully there are loads of Subsonic clients. I’ve tried several, but eventually settled on Feishin on the desktop. It’s very pretty:

Feishin’s ’now playing’ screen

What attracted me to it, though, was its built-in support for Navidrome’s smart playlists. These aren’t even properly exposed in Navidrome’s web UI yet, but Feishin has a visual editor that lets you create and edit them. I ended up with an identical system to the playlists I had in Tauon: a “blacklist” playlist which are tracks I never want to play, a “favourites” playlist, and then an “everything” playlist which is the entire catalogue minus the blacklist.

On iOS I’ve settled on Arpeggi. It’s not actually on the App Store yet, but available via TestFlight. It’s one of those really nicely polished apps that are obviously a labour of love, not just out to do the minimum possible to get your money. It can cache songs offline, and automatically download entire playlists, and supports all of the standard Subsonic features like rating, reporting plays back to the server, and so on.

One unexpected benefit of using a central server is that it handles reporting plays to Last.fm and ListenBrainz instead of the clients. I don’t think I’ve ever bothered to configure my mobile clients to do that before, and now it just works automagically. I’m relying on those services more for recommendations and discovery, as that’s something you lose out on when self-hosting.

Making bad decisions about bitrates

With all the moving, copying, and organising, I started thinking about how large the collection was. The songs were all in different formats, depending on when and where I’d picked them up, and I couldn’t tell the difference between them. I did a test and transcoded an MP3 file down to 128kbps, and still couldn’t tell the difference. So armed with that sample size of 1, I transcoded the entire library and saved so much space.

I don’t remember which track I did that first test with, but it must have been a very unlucky pick. I quickly started to notice the distortions caused by the low bitrate. It was particularly bad in any song with a lot of treble, and started to really annoy me. I started a painful process of reimporting things in their original format. Beets came in clutch again, both with the import process (if you import a duplicate album, it asks if you want to replace the original, and shows the format and bitrate of them for comparison), and keeping track of what was left to fix (beet ls bitrate:..128000).

Having started paying more attention to the sound quality, I think I’ve been nibbled on by the audiophile bug. I’ve been trying to get new music in FLAC format where possible. I’m pretty sure I can’t tell the difference between a decent bitrate MP3 and a FLAC, but maybe if I got a better DAC and some nice headphones…? Someone please hide my credit card!

As for the library taking up a lot of space, I now realise it’s a price worth paying. I might need to swap out the server to one with more storage at some point in the future, but it’s generally worth upgrading every few years with rented dedicated servers anyway, as you often get more for the same amount of money. Next upgrade I’ll just make sure there’s an appropriately-sized disk instead of focusing entirely on RAM and CPU.

Writing more code

Naturally, this whole process spawned several side projects. When browsing albums in Navidrome, I was a bit upset that the album art wasn’t all a consistent size. I thought about scripting something to crop them consistently, but then I had a better idea, and jewelcase was born. It takes the album art, crops it down to a consistent size, and then renders it inside a jewel case. It applies some slight effects, like adjusting the colours, rounding the corners, and tweaking the edges so it looks a bit more real. I don’t know why⁴, but every time I see the effect it gives me a little spark of joy.

Album art, before and after jewelcase is applied

The other project is BASS, a tool that uses the Subsonic API to grab information about my music catalogue, and then generates a “Daily Mix” playlist. It uses a system of weights to select tracks semi-randomly, biasing towards favourite tracks, those that haven’t been played much, and a few other criteria. This gives me a nice balance between having my favourites on repeat, and exploring the full library at random.

All the weights in BASS are customisable, so I can tweak it to my heart’s desire, and anyone else can also run it and configure it entirely differently to me if they want to. I can’t imagine I would’ve been able to do that if I were using Plex!

I was running a version from git as the stable release had fun dependency issues on Arch, so it’s possible this wouldn’t be an issue in normal use. I also started backing up the database, but it’s still annoying to have to restore it. ↩︎
A “favourites” playlist for me, and a more “family friendly” playlist for when I’m playing music out loud that has a bit less screaming/swearing/etc. ↩︎
One of the reasons for starting this was being annoyed by the periodic sync to my phone, obviously it makes perfect sense to introduce a new, different periodic sync. ↩︎
Nostalgia? A little bit of OCD? Both? ↩︎

Escaping Spotify the hard way

2025-07-25T00:00:00Z

I realised my media consumption was too close to this for comfort.

For the longest time I used Spotify for all my music needs. And I listen to a lot of music: sometimes actively, but mostly passively as background noise. I cancelled my premium subscription last December, and stopped using the service entirely. Why? There’s a bunch of reasons.

Let’s talk about the money first. Spotify launched at £9.99/month, and stayed that way for over a decade. Then in 2023 it went up to £10.99/month. That’s probably fair: the economy was in the toilet, and they haven’t changed their price in so long. Then in 2024 they upped it again to £11.99/month. Hmm. The service they were providing me didn’t improve in that time. I didn’t want audiobooks in my music player, I didn’t want an AI DJ that spouted inane comments at me. Paying them more money to do things I didn’t want seemed silly, and the money that actually goes to the artists is both so small and gets split in such a convoluted way that it’s not worth even thinking about.

My bigger concern was how uninvolved I became in choosing what to listen to. I leaned hard on their algorithmic playlists like “Discover Weekly” instead of manually curating playlists. But they ended up developing this weird feedback loop where it kept playing a country band¹ that I didn’t particularly like, but also didn’t dislike enough to skip. That acted as positive reinforcement, and they kept coming up everywhere. There were definitely ways to solve that by changing how I used Spotify, but the realisation that I was basically just consuming whatever was fed to me made me want to try something completely different. So I decided to go back to buying music instead. Which is where things got… complicated.

Getting some MP3s will be easy, right?

I figured with the money I was no longer giving to Spotify, I could just buy an album or two a month and slowly build up a nice music collection. I already had some music kicking around from before the streaming era, so there would at least be some variety in my listening while I got started. Where to buy music from, though?

Amazon used to do DRM-free music, but as far as I can tell it all got folded up into their own streaming service. Some smaller bands are on Bandcamp, but you won’t be able to grab Taylor Swift’s latest album from there. Qobuz have a good catalogue, but some of the stuff is pricey². It’d be cheaper to buy CDs and rip them like it was 1998 again.

I finally stumbled across an unlikely answer: the iTunes store³. This is still somehow separate from the behemoth of Apple Music, and if you fire up the iTunes software you can indeed buy reasonably priced, DRM free music. For comparison, 1989 (Taylor’s Version)⁴ is £12.89 (plus delivery) on CD from Taylor’s official website, £16.79 in CD quality from Qobuz, and £12.99 from iTunes.

Now, I use Linux, so using iTunes isn’t exactly easy. I ended up running a virtual machine with Windows on it. Every time I wanted to buy an album, I’d boot the VM, open iTunes, search for the album, press the buy button, enter my password, wait for it to download, copy all the files to a shared drive, and then back on Linux copy those files into my music directory. Smooth, right? But it worked. Earlier in the year I switched computers, though, and didn’t want to bother with the VM rigamarole. Spoiler alert: I didn’t make things any simpler.

Do you guys not have phones?

I tried a lot of things to avoid setting up a Windows VM again. I’m pretty sure I went through most of the 7 stages of grief in the process. I tried to get Apple Music to work, because that was obviously where all their development was focused, but you can’t actually buy music there (at least not on any version I could run on Linux). I tried running iTunes under Wine, but it just wouldn’t work. I looked into third-party clients, but unsurprisingly they didn’t go anywhere near payment flows.

I eventually realised that I have an Apple device in my pocket. After a bit of searching, it turns out there is actually still an iTunes app for iOS⁵. I bought an album⁶ to see if I could exfiltrate it. I connected my phone to the computer, paired it with idevicepair and then mounted the storage using ifuse⁷. Looking around, I could see a bunch of m4a files, and I could play them. Success!

Except… the file names were random hex strings, and they had no metadata. Yuck. I grabbed a copy of MusicBrainz Picard and had it sort out the mess. I stuck with this process for a while, but matching albums in Picard was sometimes a pain. MusicBrainz does a great job of figuring out what the tracks are, but it struggles to tie those back to a single edition of an album. I wasn’t aware how many subtly different versions of albums there were until I had to manually find the one iTunes had given me. Not fun. Eventually I got so fed up with this that I did something about it.

Plists all the way down

Armed with an instance of Claude Code, I set out to see if I could write some Go code to import the files properly. There were plists in the directory with the m4a files, and I know enough to know that they’re where all the juicy metadata lives on iOS. Maybe we can parse them and do something useful?

There’s a nice plist parser written in Go already, so I got Claude to write a program to dump the contents of one of the many plist files in the directory. Inside was all the metadata for one of the tracks. Yay! Just one small problem: there’s no way to link the plist file to the audio file. There’s one plist file that has a real name, though: StorePurchasesInfo.plist. I had Claude translate it to JSON and found that it contained a data field with a bunch of binary data. Huh.

I thought this was probably a dead end, but stuck the base64’d data into CyberChef and fiddled around a bit to get a hexdump of the binary. Six characters jumped out at me: bplist. I went back to Claude and suggested this might be a plist-in-a-plist scenario. Claude then got very confused because it couldn’t understand where the base64 was coming from⁸. After some LLM-induced suffering, I eventually got the contents of the inner-plist, and for each track it had a list of the audio file, the metadata, and the album art. Yay!

With the data figured out, it was fairly simple to get Claude to write code to parse everything and link them together, and after that move the files into their correct place in my library. I also had it take the metadata from the track’s plist file and write it into tags on the m4a so my media player didn’t have to understand Apple nonsense. I looked around for a Go library to do this, but couldn’t find one supporting m4a files, so ended up just shelling out to exiftool.

As a bonus, I made the tool automatically make a temporary directory and use ifuse to mount the phone, then unmount it when it’s finished. So now all I have to do is plug my phone in, and run import-music on the command line⁹. It’s a very nice quality-of-life upgrade that I probably wouldn’t have bothered with if I didn’t have Claude Code to speed the process up¹⁰.

Sometimes I actually play music too

With all this talk about buying and sorting music, I almost forgot about the most important bit: listening! I use Tauon, and it looks like this:

Tauon, showing off a wide range of different music in my library.

I tried a bunch of different music players, but Tauon hits the sweet spot of being simple enough to use but capable enough in the right places. I particularly like the playlist generators. My “Music” playlist just auto-imports all music in my “Music” folder, then I have a “Classical” playlist with a generator of s"Music" g"classical" auto. That makes it use the “Music” playlist as a source, filter on tracks that have “classical” in their genre, and automatically update when the base playlist changes¹¹. The “Disliked” playlist does the same but filters on rating: s"Music" a rat=0.5 auto. That takes all tracks (a) from the Music playlist, then filters it down to only those that have a rating of 0.5 out of 5¹². Finally, the “Normal” playlist imports everything from “Music” that’s not in one of the others. It sounds a bit clunky, but it works well in practice and I like the way it works.

Tauon in general just seems to work the way I’d expect it to, which is refreshing. You can just start typing anywhere to search for a track, hit enter, and it starts playing. It has keyboard shortcuts for other operations, and standard features like reporting to last.fm and other sites.

Tauon also supports transcoding and copying tracks to a music player or a phone. I use this to sync my main playlist to my phone. I’ll give you a minute to just bask in the glory of the rube goldberg machine I’ve created to move music from my phone, to my computer, and ultimately back to my phone. This does actually serve a purpose, though: it lets me control which tracks are on my phone. I don’t have to deal with excluding genres or tracks I dislike on the phone in addition to the computer. In the future I might opt to just sync a subset of my tracks to keep the storage size down. I’m telling you it makes sense! Stop looking at me like that!

Paying Attention Pays Off

I mentioned one of my aims for getting away from Spotify was to feel less like I was just consuming whatever’s in front of me. The corollary to that is how do you discover new music without an algorithm to feed it to you? I’ve ended up subscribing to a few blogs, paying more attention to music-related news, and being more aware of songs on the radio and from other sources.

When I find a song I like these days, I tend to listen to a few other tracks on the album (via YouTube, normally, as it’s the least friction) and decide if I want to buy it. When I do, I sit down and listen to the whole thing in order. It’s a radically different experience to just hearing a song now and then. There are themes and connections between tracks that you just miss if you listen to songs at random. Of course, you could do that on Spotify, but I don’t think it really lent itself to it.

My favourite example of this is my rediscovery of Linkin Park¹³. I’m of the age where they were around as I was growing up. I knew a couple of their big hits but younger-me wasn’t that into rock¹⁴, so I didn’t pay them much attention. Then I caught Up From the Bottom on the radio, and from there ended up buying and listening to all of From Zero. It’s an amazing album. The Emptiness Machine has become my favourite song: not only is it a great tune, performed well, it’s also a fantastic introduction to a new era for the band and to Emily Armstrong as the new vocalist. The rest of the album then builds on it to show off what they can do.

I’ve since gone back and reconnected with a lot of Linkin Park’s older albums, too. And from there discovered a lot of other rock bands I really like. Could this have happened with Spotify? Maybe, but it seems unlikely. It had me in a country-band-I-can’t-remember filter bubble, it seems pretty unlikely it’d drop some Linkin Park on me out of nowhere. And the passivity that came along with it would have meant that I probably wouldn’t have paid enough attention when I heard it from elsewhere.

Would I recommend that everyone runs out and cancels their Spotify subscriptions? Eh, probably not. If it works for you, that’s fine. Discovering recursive plists is fun for me, but I appreciate it’s not everyone’s cup of tea. What I would recommend is being a bit more deliberate in your choice of music. Don’t just tune in to a random playlist, or let the ‘DJ’ decide what to play. Find something, and actually listen to it. Then recommend it to me. I want more music!

I can’t even remember the name of the band, that’s how much I was into them. ↩︎
And they’re annoyingly deceptive about it. All the prices are “From £x”, where x is the discounted price you’d get if you paid them £15/month. ↩︎
I’d link to it, but… there isn’t a website. That’s not how things were done in the 1990s, silly. ↩︎
I don’t know why I’m so hung up on Taylor Swift in this post. ↩︎
Again, unrelated to the Apple Music app. ↩︎
It probably wasn’t a Taylor Swift album. Maybe. ↩︎
The Arch wiki has a useful page on this (of course). ↩︎
We were translating the plists to JSON, and if you serialise a byte array to JSON in Go it ends up as a base64-encoded string. Claude was then adamant it needed to base64 decode the binary plist. It did not. ↩︎
I just had the sudden realisation that I can probably automate running the import-music tool whenever I plug my phone in using systemd… ↩︎
I feel like I say that a lot lately. ↩︎
I like classical music, but it’s a mood, and I’m often not in that mood. ↩︎
I basically use this to filter out those introduction/bridge tracks on albums that are just talking and not singing. ↩︎
Surprise! My library isn’t actually just Taylor Swift songs. ↩︎
Younger-me was a dumbass, in some ways. ↩︎

Home Automation Without the Megacorps

2025-05-21T00:00:00Z

I first experimented with home automation in 2016, by picking up a Samsung “SmartThings” hub. It was terrible. The UI to configure things was slow and clunky, firmware updates were applied whether you wanted them or not, and everything stopped working if their cloud services stopped. You were also locked into whatever integrations they deigned to support, of course. After that broke for the umpteenth time I scaled back and for years the closest I got to home automation was a couple of Hue bulbs.

Recently I’ve been building it out again, though. This time using off-the-shelf components that interop using Zigbee, open-source software, and some code I wrote myself. It’s great; it runs entirely locally and has had basically zero downtime. The Zigbee ecosystem lets me integrate all sorts of things without having to spend lots of money on “smart” alternatives. I think I’ve spent less on this incarnation than I did on the original SmartThings hub all those years ago (even without adjusting for inflation!).

My current setup

I run everything on a Raspberry Pi 4, with a Sonoff USB Zigbee adapter based on the CC2652P chipset¹. Interfacing with the Zigbee stack is handled by zigbee2mqtt (z2m for short), an open-source project that basically bridges your devices to an MQTT broker². When a device reports some data, it will send a new message over MQTT; when you want to make a device do something you just post a message back. It’s incredibly lightweight, but supports a huge array of devices out of the box. And as it’s just using MQTT, it’s trivial to integrate with other software or build on top of.

I know a lot of people building out this kind of home automation use Home Assistant, but I don’t get on with it terribly well. It felt incredibly sluggish, and the entire project is just a bit… much. I want a binary or package or docker image I can just run, not an entire operating system. That’s not how computers are meant to work! In contrast, z2m is simple to set up, super light weight and responsive.

Anyway. z2m exposes Zigbee devices over MQTT, so I wrote some code in Go to connect to the MQTT broker, and listen to the messages. It’s grown a bit beyond this now, and I’m skipping some boring bits like error handling and JSON parsing, but at first I had something like:

for {
    message, topic, err := c.ReadSlices()
    
    if string(topic) == "zigbee2mqtt/desk-button" {
        if strings.Contains(message, "single") {
            c.Publish(nil, []byte("{\"state\": \"TOGGLE\"}"), "zigbee2mqtt/room-lights/set")
        }
    }
}

I think I actually made this harder to read by trying to simplify it here, but hopefully you can follow that it was relatively straight forward to listen for a particular action to happen (in this case me “single”-pressing on the device called “desk-button”) and then make another device do something in response (toggling the state of the “room-lights” device).

So what actually are these devices? At present in z2m I have the following:

Some generic buttons
An air quality sensor (USB powered), and a separate temperature sensor (battery powered)
A light switch
Some 240V relay modules, that I use to turn non-smart devices on and off
Some USB relay modules, for the same purpose
Some “smart” plugs that I mostly use to monitor power usage
A motorised blind roller

I think all of these are either Tuya or Moes branded, and were all sourced from AliExpress. You can get the same things from Amazon or elsewhere, but they tend to be 3-4x more expensive for the same product.

One of the cool things about Zigbee devices is that the powered ones work together to create a mesh network, so you don’t have to worry about network repeaters or signal strength like you do with Wi-Fi networks. z2m even makes a map showing the connections:

The network map produced by z2m. You can see how all the powered devices form a mesh that the lower power ones can connect to.

Some interesting automations

A Zigbee relay spliced into the power cable for the fan

So what do I actually do with all of this? Some of it is just what I’ll call “laziness automation”: I want to be able to turn on the lights without getting up and walking to the light switch. So there’s a Zigbee button on my desk that does it. Then there are some less manual automations: my blinds are automatically closed at sunset³, for example. It feels a bit trivial, but it’s surprisingly nice just not to have to think about that at all.

Another nice quality of life automation is the light I have above my monitor. It’s USB powered, and I now have it going through a Zigbee USB relay that lets it be toggled on and off. Then I have a small agent running on my desktop that turns the light on when the computer is unlocked, and off when it locks or shuts down. I keep meaning to make a “film mode” that detects when I’m watching a film, and turning all the lights and blinds down, but I haven’t got around to it yet.

The most complex automation is probably for a window fan. It’s not smart in any way, so I cut the power cable and inserted a Zigbee relay. The whole thing is housed in a little project box to keep it secure. The relay basically acts as a switch: the live wire leading to the fan runs to the “normally open”⁴ contact, while the upstream power goes to “common”. When the relay is told to turn the fan on, the two get connected and the fan gets power. Oh, it’s also not actually a window fan, but I designed and 3D printed some adapters so that it sits right in the window.

So now we have a window fan that can be turned off and on automatically. But I don’t want to have to press a button to do that. I’m lazy, remember? Instead, I made it so that the Go code constantly monitors the temperature reported by the air quality sensor, and queries the free OpenWeatherMap API to get the rough temperature outside. It can then turn the fan on if the room is too hot, and outside is cool enough to make a difference (there’s no point in blowing hotter air in!).

A graph of room temperature, showing the effect of the fan being turned on and off

I don’t want it to do that all the time though. The room doesn’t need to be cooled if I’m not around. There are various Zigbee presence sensors you can get, but the cheaper ones seem to be of dubious quality. Instead, I wrote some code to guess whether I’m present. It uses the state of the monitor light as a proxy for “is the computer in use”, and then makes some guesses based on the last time the computer was used and the current time (if I turn the computer off at midnight it probably means I’m going to sleep; if I turn it off at 2pm it probably means I’m going out somewhere).

You can see in the graph that the fan has a decent impact on temperature. I coded it to cool the room to 19 degrees, but then not turn on again until it was above 20. This prevents it flip-flopping on and off constantly. You can clearly see the pattern in the graph, as it actively cools and then slowly the room warms back up. This arrangement is much better than being woken up at 5am because it’s painfully cold. Trust me.

Bonuses: metrics and 3D printer

One of the things my custom Go code does is collate all the various stats reported by the Zigbee devices, and inserts them into a VictoriaMetrics database. I originally hosted this on the Pi itself, and it performed fine, but I’ve since moved it onto a server so that I can use it for some other things as well.

I set up Grafana to point to VM, and can create dashboards showing power usage, what devices are turned on when, and a bunch of environmental conditions. This also makes it easy to spot how good the data coming from the devices are. For example, the air quality sensor reports a figure for the amount of Carbon Dioxide in the air, as well as the amount of Volatile Organic Compounds (VOCs). The graphs are basically identical, but on a different scale. It turns out this particular device has no actual way of detecting CO₂, so it just “calculates” it from the VOCs figure. Useful to know if you want to actually use that data.

Recently I came across a go library for interacting with Bambu Lab printers, so I’ve also hooked that into my automation. It exports metrics about the printer, so I now have a way of seeing what’s going on when I’m not physically present⁵. I even added a HTTP endpoint (exposed over Tailscale) that shows pictures from the built-in camera.

On the automation front, I’ve made it automatically turn off the printer’s light when it finishes a print, and also added push notifications via PushOver whenever the state changes. No longer will I be sat in another room blissfully unaware it ran out of filament seconds after I walked out the door!

Was it worth it?

These days you could probably just buy some kind of ‘smart home’ hub that works well enough, and do most of what I’ve done with a lot less effort and no coding. I’m still of the opinion that for something so essentially local, it should itself be managed entirely locally. I don’t trust companies like Google or Amazon not to kill their products, or change or remove an API I rely on.

Obviously the “Not Invented Here” approach of coding everything yourself doesn’t suit everyone, but as someone who enjoys coding and enjoys having things work just so it works very well for me.

It turns out the chipset is important. I initially used a similar Sonoff dongle that used a CC2531 chipset, and its performance wasn’t great. It often failed to pair with new devices, and dropped links to existing ones. The zigbee2mqtt docs do explicitly advise against the CC2531 chips for that reason. At the time they recommended CC2652Ps, so that’s what I went with. If you’re starting new I’d go with whatever their latest recommendation was. ↩︎
MQTT is basically a network protocol for publishing and subscribing to arbitrary messages. A broker is the thing that sits in the middle and routes the messages. I use Mosquitto but any will do. ↩︎
They originally also re-opened at sunrise but that was a terrible mistake. Who knew the sun rose so early?! ↩︎
“open” meaning “there’s a gap so it doesn’t work” not “open for business”. This confusion in terminology also extends to drawbridges. ↩︎
I use the printer in LAN mode, which means there’s no way to monitor it from a phone, even if you’re connected to the same network still. ↩︎