How does PageSourceSearch know what book-browser.val.run is built with?

From the site's own source code. The crawler stores the exact bytes of its pages and first-party scripts; the libraries are recognised by fingerprinting that code against known releases, the identifiers are read out of the tag snippets, and the third-party hosts are the script, iframe and stylesheet sources in the HTML and the absolute URLs inside the scripts. Nothing is inferred from headers or guessed.

How far back does the history of book-browser.val.run go?

To the first crawl the timeline lists. Every crawl records what the site looked like; when a file's content changes, its earlier version stays viewable because the stored chunks are never deleted, only mapped. A crawl that finds a file unchanged adds no copy.

Can I see an older version of a script from book-browser.val.run?

Yes. In the stored files list, every date under a file opens the version that was live at that crawl, with the same viewer as the current one. The raw bytes can be downloaded from there.

Which other websites use the same tracking IDs as book-browser.val.run?

Each identifier links to its reverse lookup, the list of every site in the index whose source carries the same id: the sites one analytics property or tag manager container is shared across.

Site profile

book-browser.val.run

Built with react, react-dom. 1 page and 8 stored files, last crawled 2026-10-03.

2 libraries 0 identifiers 4 third-party hosts 1 crawl open the site

Technologies and libraries

Recognised by fingerprinting the stored files and bundles against known releases; a version is the release the bytes match.

Library	Version	Seen
react		2026-10-03
react-dom		2026-10-03

Tracking, tag and verification IDs

No analytics property, tag manager container, pixel or site-verification token was found in the stored source.

Third-party hosts

Hosts outside book-browser.val.run that its pages load scripts, frames or stylesheets from, and that its own scripts name in absolute URLs (connect). Each links to every site loading from the same host.

Host	Loaded as	Found in
bookhive.buzz	connect	view source
cdn.twind.style	script	view source
esm.sh	connect	view source
www.w3.org	connect	view source

Stored pages and scripts

The newest stored version of each file, newest first@if (p.FilesTruncated) { (the 500 newest of 8) }. Versions are the crawls at which the file was new or its content changed; each opens the file as it was then, rebuilt from the same stored chunks.

File	Kind	Size	Collected	Versions
https://book-browser.val.run/frontend/components/Login.tsx	js	3 KB	2026-10-03	2026-10-03
https://esm.sh/react	js library	not fetched	2026-10-03	2026-10-03
https://esm.sh/react-dom/client	js library	not fetched	2026-10-03	2026-10-03
https://esm.sh/react/jsx-runtime	js library	not fetched	2026-10-03	2026-10-03
https://book-browser.val.run/shared/types.ts	js	366 B	2026-10-03	2026-10-03
https://book-browser.val.run/frontend/components/App.tsx	js	36.1 KB	2026-10-03	2026-10-03
https://book-browser.val.run/	html	512 B	2026-10-03	2026-10-03
https://book-browser.val.run/frontend/index.tsx	js	433 B	2026-10-03	2026-10-03

Timeline

One entry per crawl, newest first, with what changed since the crawl before: libraries, identifiers, third-party hosts and files. Historical versions stay viewable because the stored chunks are shared between versions, never copied.

2026-10-03 first crawl

1 page, 8 files, 40.3 KB; 2 libraries, 0 identifiers, 4 third-party hosts
2 libraries added
- react
- react-dom
4 third-party hosts added
8 files added

Questions about book-browser.val.run

How does PageSourceSearch know what book-browser.val.run is built with?: From the site's own source code. The crawler stores the exact bytes of its pages and first-party scripts; the libraries are recognised by fingerprinting that code against known releases, the identifiers are read out of the tag snippets, and the third-party hosts are the script, iframe and stylesheet sources in the HTML and the absolute URLs inside the scripts. Nothing is inferred from headers or guessed.
How far back does the history of book-browser.val.run go?: To the first crawl the timeline lists. Every crawl records what the site looked like; when a file's content changes, its earlier version stays viewable because the stored chunks are never deleted, only mapped. A crawl that finds a file unchanged adds no copy.
Can I see an older version of a script from book-browser.val.run?: Yes. In the stored files list, every date under a file opens the version that was live at that crawl, with the same viewer as the current one. The raw bytes can be downloaded from there.
Which other websites use the same tracking IDs as book-browser.val.run?: Each identifier links to its reverse lookup, the list of every site in the index whose source carries the same id: the sites one analytics property or tag manager container is shared across.

Look up another site, browse sites by tracking ID, third-party host or technology. Site owners: see the crawler page for how stored pages are removed.