landingdiff

Which of a set of landing pages is the odd one out, by counting what each page puts in the shared design system. Repository → Latest tag: v0.2.0; this page is written from its README at that tag. The README at that tag gives no install line; one was added on main on 2026-10-26, after checking that it builds:

go install github.com/go-fleettools/landingdiff@latest

landingdiff ../landing-go-*/layouts/index.html

                               go-authn go-fileshare  go-pkgx go-pdfkit   spread
headline line 1, characters          14           10       19        23   10..23
items in the trust band               3            3        3         4   3..4  <- go-pdfkit
buttons in the hero                   2            2        2         2
...
go-pdfkit is alone on 2 measure(s)

(An excerpt of the README’s example.)

Why counting, and not diffing

The landings share one styles.html, so “aligned” cannot be checked by diffing the design system. What drifts is what each page puts in it: a band with one more item than fits on a line, a navigation with twice as many links as its neighbours.

What it will not tell you

• A page is named only when the others agree and it does not: one value held by everybody else, one page holding something different. It deliberately does not flag “furthest from the rest”, which would name the smallest and the largest every time.
• It is blind to layout. A headline too long for its column is a fact about rendering, found by screenshotting the pages; use both, because neither finds the other’s.
• Read the comment on the line before you “fix” an outlier: an outlier the history explains is not drift.

To add a measure, add one entry in measures: a name and a function from the page’s HTML to a count, returning -1, not 0, when the part is not there at all.