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Dva skutečné weby nosí vzhled, který tento engine nikdy nedodával. sh.cynicky.blog je oblečený jako Ghost — úvodní karta přes celou šířku, tečkovaný rámeček, dlaždice místo prostého seznamu. arch-linux.cz je oblečený jako téma pro Hugo, konkrétně Blowfish — kompaktní lišta, blok s profilem, karty rozložené jako úplně jiná domovská stránka. Ani jeden nevytvořil fork enginu. Ani jeden neupravil šablonu. Oba dál přijímají obyčejný git pull.

Jeden stylesheet, načtený jako poslední

site.extra_css v config/site.yml udává cestu nebo seznam cest, které se načtou po vlastních colors.css a site.css enginu. To je celý mechanismus — skin je jeden tvůj soubor, který překresluje, co už na stránce je, a engine do něj nikdy nezapisuje, takže s ním aktualizace nikdy nemůže být v konfliktu.

Jen místní cesty: každá stránka nese style-src 'self' a stylesheet z jiného hostitele by prohlížeč prostě zahodil bez jediné chyby, kterou by kdokoli uviděl — sestavení proto vzdálenou cestu odmítne nahlas, dřív než to ticho nastane.

./blog.sh 1.8 je venku — vydání na GitHubu.

Vydání o tom, co se stane, když se něco pokazí. Každá stránka, feed a index se teď zapisuje do dočasného souboru a přejmenuje na místo, takže uložení přerušené plným diskem nebo sestavení zastavené uprostřed zápisu už nezanechá stránku v poloviční délce ani příspěvek o 0 bajtech, u kterého je starý text pryč. Studené sestavení tím zdraží zhruba o pětinu; sestavení z cache ne, takže běžný den publikování stojí přesně tolik co dřív.

Dvojí doručení už neznamená, že se něco stane dvakrát: příspěvek odeslaný z telefonu dvakrát nebo jedna potvrzenka doručená ve dvou kopiích najednou je teď jeden příspěvek a opětovný import exportu vlastního enginu už z 1200 příspěvků nedělá 2400. A adrese se už nevěří jen proto, že jako adresa vypadá — ../ ve slugu, v názvu mediálního souboru nebo v cíli přesměrování zůstane uvnitř webu, lokální nasazení zůstane uvnitř svého adresáře a přesměrování z feedu nemůže poslat stahování na localhost.

Někdo postaví celý web na notebooku, naimportuje do něj desetiletí starých příspěvků, prohlédne si každou stránku — a nic z toho ještě nikam nedorazilo. V env.sh není řečeno kam a nic dalšího na to nečeká: sestavení proběhne, archiv projde kontrolou, každá stránka se vykreslí na localhost. Sestavení neví, kde má web nakonec skončit, a vědět to nepotřebuje.

Totéž sestavení může začít na notebooku, o rok později se přestěhovat na pronajatý VPS a potom skončit na instanci Cloudronu. Mezi těmito přesuny se v obsahové pipeline nemění nic. Mění se odpověď na jedinou otázku — kam mají soubory jít — a odpovědět na ni může šest věcí.

Co o tom rozhoduje

DEPLOY_BACKEND v env.sh určuje cíl; hodnoty pod ním závisejí na tom, který to je. Všechno za tímto řádkem je u všech šesti stejné. Každý backend si vede vlastní manifest — SHA-256, velikost a čas změny každého souboru, který už nahrál — takže nasazení posílá vždy jen to, co se od minulého změnilo. deploy-web.sh --dry-run tento manifest přečte, aniž by se čehokoli dotkl.

Takhle vypadá výstup, spuštěný právě teď proti vlastnímu backendu tohoto webu:

A reader changed one border colour in site.css, ran a rebuild, and waited while the build produced, byte for byte, every page that was already there. He asked why. The answer was one word in one list, and 1.7 takes it out.

What a build writes down

Since 1.6 the build keeps a record of what went into each page it wrote -- the post, the posts around it, the labels, the numbers a page counts. On the next build a page whose record has not moved is not rendered at all. Not rendered and then found identical: not rendered. The summary at the end says how many pages were left alone, the first number to look at when a build is slow.

The record holds only while the engine that wrote it is the same engine, so it hangs off a fingerprint of what the engine is made of -- the files under templates/, lib/, build/, locales/ and config/, hashed by contents rather than by timestamp. Change any of it and the record is discarded entire, because any of it can change every page.

Why the colour cost the archive

Someone opens a post with a video in it and presses play. The connection is fine. The video is not large. Nothing happens for a while, and then the video starts all at once, as if it had been waiting for permission.

It had been waiting for the index.

Why it sits at the end

An MP4 is a handful of boxes laid end to end. One of them, mdat, is the picture and the sound. Another, moov, is the index: which frame is at which byte, how long the thing runs, what codec to hand it to. A player needs moov before it can show a single frame.

The example configuration this engine ships carries a bicycle: a tag called kolo, and under it an <svg> written out by hand. It is there because there was nothing else to put there. tag_icons took the name of an icon the engine ships or a drawing of your own, and the ones it shipped were the eight content types — text, image, video, link, audio, quote, document, chat. A tag about cycling could wear the glyph for "audio", or somebody could spend an evening with a coordinate grid.

1.7 puts fifty-five drawings in between, and gives each of them a name.

Fifty-five nouns

Counted in lib/icons.rb: the eight content types, fifty-five more, sixty-three names a tag may ask for. Grouped by what a blog turns out to be about.

Somebody sends you an article. You read it, and you have two hundred words to say about it -- not a review, the thing you noticed and one sentence about why. The post is mostly the other page, and the address it is about has to live somewhere.

Until this release the honest answer was: in a paragraph, like any other link. The card such a post opens with existed as a block -- the importers make them, out of Tumblr and out of Bluesky -- but nothing anybody could type produced one. The writer that turns a post back into markdown had no syntax for it, so edit on a link post offered to drop the card, and add <file> could not make one at all. This project's own release posts stopped being link posts after 1.3 for that reason. The tool had changed; the intent had not.

Three lines in the header

Five parts of a series written over a spring, and the third went out without its series: line. The site did what it was told. Part three sat at its date and nowhere else: off the series listing, out of the links from one part to the next, and out of the count the other four wear: part four's page called itself part 3 of 4, standing in the slot the missing post should have had. The fix was one word.

Getting to that word meant opening the article.

That is what edit does. It reads the post out of its file, writes the whole thing back out as markdown, opens it in an editor, and parses what comes back. For a post that is paragraphs and photographs the round trip is faithful and nothing is at stake. For a post carrying something markdown has no form for, it is not.

Seven rows

props <slug> gains [e] -- on a draft, on a scheduled post and on a published one alike.

The post is written on the tram: a title, four paragraphs, two photographs with their descriptions. The switch above Send says Draft, which is what it says unless it is moved. Send, and the answer card comes back with the preview address. Then it sits. Putting a draft out was a command, and a command wants a terminal, and the tram has none.

1.6 asked for that decision at the wrong end: publish at the moment of sending, before the blog has rendered anything, or see the blog's own page and then find a keyboard. 1.7 closes that, and then closes the road the answer takes back.

One file, down the same connection

The answer card for a draft now carries a Publish button. Pressing it sends one file, called publish.txt, holding the slug and nothing else -- through the same share sheet, the same two shortcuts, the same SSH connection the post itself took.

Five posts have covered the things 1.6 is about. This one is the rest, in the order an operator meets them.

A way out of the trash and the versions

Both stores had a way back — restore, and the version picker in the post's properties — and no way out, so both grew for years and nothing said by how much. empty trash and empty versions each print what they are about to remove, in items and in megabytes, and require that count typed back before anything goes. empty versions keeps each post's newest version, because versions exist to answer "give me back what I just overwrote". doctor now notes a trash with posts in it, as a note rather than a fault: on the installation this engine was built around, the only way to see it was du on the server.

A photograph stored once

public.nosync/ used to hold a second copy of every picture. It holds a hardlink now, so the pictures take half of what they did — 1.8 GB on this project's installation. It saves nothing in a backup, and that was measured rather than assumed: 200 files under two names, 101 MB on disk, 201 MB in the backup. Nothing to do; the first build after the upgrade makes the links.