Colophon

This page is about the site itself: where its text comes from, what its date means, and the small set of colours, type sizes and shapes that every page is built from. It fits on one screen so that you can read it instead of the stylesheet, and so that the set stays small enough to remember. A set you can remember is one you reuse rather than extend.

The values below are generated from site-css/identity.css. The description beside each colour is the comment on that token's line in the stylesheet. If this page and the stylesheet disagree, the page is wrong, and so is the check that compares them.

Where the text comes from

Prose is written by hand in a file. Tables are generated by the build. You can tell the two apart by looking, and there is no third kind of content.

A page's source file is content/ plus its route: /components/button.md is written in content/components/button.md, and /writing/voice.md in content/writing/voice.md. Every page prints the path of its own source file in the footer, whether or not that file exists yet, so a page with no guidance on it tells you where to write some.

A page exists because a file asked for it, and deleting the file removes the route. Component pages are the exception. A component can appear in appsignal-server before anyone has written about it, so those pages are stamped from one template and the source file is an optional overlay. Everywhere else, the file named in the footer holds every sentence on the page.

Every list on the site is generated from the registry of pages the build wrote, so a list cannot name a missing page or leave out an existing one. This is checked, not assumed.

Hand-written prose gets one check: every component, class and token name it mentions is verified against the product's code at build time, so a page cannot refer to something that no longer exists. That is all it catches. Nothing can tell whether advice has stopped being true, and nothing on this site dates the prose. The next section explains why.

Hand-written pages do not state values. A colour or a size typed into prose would be a second copy of a fact the generated pages already carry, and the second copy is the one that goes stale. Those pages link to the value instead.

There is no full-text index. The box in the rail is a jump-to: it matches the names of pages, components and CSS classes, and the keywords authored for each component, so typing alert reaches the Message page. It does not search the prose. The lists are complete rather than paginated so that find-in-page works on whichever page you are already reading.

The date

Every page carries the same date, and it means one thing: when we last read the product. The footer line Read from appsignal-server@… on … is identical on every page. It is not the build date, not the date anyone edited the page, and not a claim that anything is current.

What it does let you do is distrust a page precisely. Every generated value was read from the product's source at that one commit, so the page is true of that commit and of nothing later. If the product has changed since, this site keeps the old answer until someone moves the pin and rebuilds. When the product and a page here disagree, trust the product. The commit is how you show the page is behind.

Whether the product has moved since is not knowable from here. The build reads a pinned commit and has no network access, so the date says when we looked and nothing about what has happened in the meantime.

Hand-written pages carry no date of their own. They used to: a last_modified: field typed by hand and printed as "last curated …", meant to warn that hand-maintained text goes stale. It was itself hand-maintained and unchecked, and nine of the twenty-one pages that carried it printed "an unrecorded date". It was removed on 2026-09-11 rather than automated. A date derived from git records the last commit that touched the file, and a mechanical pass over frontmatter would re-date every page without a word of prose changing, which would make the text look fresher than it is. No date is better than a meaningless one.

A page's edit history is one click away. The footer links to the file the page is written in, and the repository holds the commits.

What this site publishes about our own repositories

Deep links into our own repositories, and the paths they carry, are allowed. This was settled on 2026-09-11. The audience is internal, so a redaction costs the reader it was meant to protect.

The pipeline has not caught up. Paths read from the product's source are still stripped on the way in by a redactor written under the earlier, stricter rule, so a page naming a stylesheet gives you the filename but not the directory. That is a leftover, not a policy, and removing it is outstanding work.

What stays out regardless: code that is not already in the published Storybook, and anything that looks like a credential.

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