jakstys.lt/content/log/2023/end-of-summer.md

title	date
End of Summer 2023	2023-08-27T15:37:00+03:00

Just before this summer I [laid out my roadmap]({{< ref "log/2023/roadmap-summer-2023.md" >}}) for, well, the summer. Here is a quick retrospective. Weird order, because it is somewhat chronological.

Project 2: my take on universal headers

During SYCL 2023 I was told that Johny Marler expressed explicit interest in the project. I have much higher hopes in him than myself -- at which point I decided there are better things to do and shelved universal-headers. Non-ironically, I am no longer working on compiling lots of C++ code, so this area has less ROI for the potentially invested time.

Project 1: city limits

Showing any spatial result requires a background map. In the spirit of protomaps, I looked into how to host the base maps myself. That was quite a rabbit hole with twists and turns, designed to misguide the non-initiated.

Since maps are simple pictures (PNG squares) with a bit of JavaScript to download and display them, I wanted to "keep things simple" and serve the files with a plain web server. Which meant pre-generating many tiles from the OpenStreetMap data. Turns out, this results in 5 million tiles for Lithuania:

{{<img src="_/2023/tile-calculator.png" alt="screenshot from geofabrik.com" caption="Pre-generating Lithuania to zoom level 17 would output 5 million tiles." hint="graph" >}}

Generating 5 million tiles takes at least a day on my small server (I gave up after this time having decided to seek for a different approach). To generate tiles one still needs the usual suspects — PostGIS and friends. So pre-generating Lithuania with a complex process and many dependencies and then serving them via a web server does not really save on "simplicity".

After I discarded the pre-generated tiles idea, I looked at how to serve them on the fly. This is how most of the world does it, so this is the beaten path. The usual OpenStreetMap stack consists of:

1. PostGIS with all the data, and the tools to keep it up to date.
2. mapnik, a map renderer. A library written in C++.
3. renderd: a daemon that renders map tiles using mapnik.
4. mod_tile: An Apache module that connects to renderd and spits the tiles out in HTTP.

I have no interest in maintaining Apache for just the base maps, so mod_tile would need to be replaced. go_tile is a good candidate. During my earlier pre-generation phases I found that image/webp are about half the size of PNG. As a result, mod_tile can now render image/webp and go_tile can use it.

During the middle of all this I understood how my personal stack is unfit for the purpose of ad-hoc projects like this: if I put out something for the world to see, I want it to keep working for years. Serving the base tiles is just part of the problem, but already includes many more moving parts than I would like to maintain on my crumbling servers. So I decided to shelve this mapping project and spend some attention spans to "my infrastructure".

Project 3a: home lab "infrastructure"

As alluded in the previous section, the "home infrastructure" was not in a shape I would be happy to maintain long-term. If I start a project that I can show off, it needs to work for a long time with no or minimal maintenance.

At the beginning of Summer I ran two Debian servers that needed to be upgraded. They have been configured by two thousand lines of Ansible YAMLs. I felt that writing the yamls were a necessary pain, so grinded it. It was so painful to configure stuff in Ansible that I wrote my own http server instead of using nginx; I wrote my own DNS server instead of using bind or nsd. And I was ready to write even more software from scratch, myself, just because it was so hard to configure out-of-the-box components with Ansible.

In an unrelated conversation with my ex-colleague and good friend Ken Micklas, he suggested taking a more serious look into NixOS. I spent most of the summer's "computer time" understanding and dabbing at Nix. Boy it was a great decision. Time will tell, of course, for how long it was a maintainable one, but it shines pretty bright colors now.

As of writing, I have the following on a small Odroid H2+ computer in my closet:

• This web server (jakstys.lt).
• Syncthing to synchronize documents, photos and podcasts between my laptop, phone and server.
• My code hosting instance, which is also a "single sign-on" provider. I authenticate to Headscale, Grafana and Gitea using it. I still have separate passwords for IRC and Matrix. IRC has no SSO for being IRC, and for Matrix it's "on the roadmap" for a while now.
• Home VPN for all my devices.
• Prometheus + Grafana, accessible only via the personal VPN.
• IRC bouncer, so I can visit #zig on libera.chat.
• Matrix server, so I can still visit NixOS channels. Blog post about my declining usage of Matrix is coming soon.
• Automatic updates with automatic rollbacks when upgrades fail.
• DNS server. Here is the zone config and the server config. This allows me to not use the "free" DNS providers (I have used one before, but had to move after a day-long outage). Having my own DNS server allows me to have letsencrypt certificates with DNS verification.
• All on an encrypted root file system in ZFS, with nightly backups to rsync.net. The encrypted file system allowed me the liberty to add private data on the server: family photos, chat histories, later -- host a password manager for my family.

DNS server is a reason why I run another server. The second server is an AArch64 virtual machine in Hetzner for €3.98/month which serves two purposes:

• The DNS server.
• Remote unlocking of the home machine's root partition. The servers keep trying to ping and unlock each other in case either of them reboots (hopefully not both at the same time).

Why encrypted root partition at home? Because I don't want my family photos and personal documents unencrypted.

Project 3b: home and vacation

Originally I planned to take some time off and do all those projects. But after a couple of weeks it turned out that I am unfit for such a regime: the full day goes by and I do not feel like I have achieved more than I would normally have if I were employed.

So at mid-August I started actively interviewing. It is ongoing now; I expect to have a job again sooner than I originally thought.

I will keep you posted! Next -- Matrix.