What we thought about when we built it

Last updated: 31 July 2026 · Describes build 1.0.47

catchroll makes files that leave your machine only when you send them — often straight into an AI conversation. That raised design questions we took seriously. These are the answers we chose, and why.

1 · The frame you draw is the boundary

Whatever you framed is what’s shared. The tool may include less — it must never include more. And the boundary is geometric: your rectangle, not what happened to be visible inside it. Text sitting under an opaque panel inside your frame is still captured; text outside your rectangle stops at the edge — a cut line can carry a truncated fragment, but never a readable sentence from outside your frame. Practical tip: close floating chat and DM windows before you capture, so they aren’t inside your frame to begin with.

2 · Redaction destroys; it doesn’t cover up

When you black out, blur, or pixelate part of a capture, the pixels are overwritten in the image itself — not an overlay someone can peel back. And because a capture can carry the page’s text and a link back to its source, redacting also removes the saved text and the source pointer from every file you save or export. One honest trade-off: redacting any part of a capture destroys that whole capture’s saved text. There is no reliable way to know which words sit under the redaction, so we destroy all of it rather than risk leaking what you hid. If one part of a page is sensitive, capture it separately and redact that capture.

3 · No fingerprints

Files exported from catchroll carry no identifier for you or your installation. A per-install signature was proposed early on and rejected outright: a token like that turns every file you share into a tracker. What your exports do carry is what you captured — the text, the page title, the address, and when you took it. That’s the point of an export, and it’s yours to send or not send.

4 · The footer informs; it never persuades

Exports end with a short, fixed attribution line, so a reader — human or AI — knows what kind of file it’s holding. It states facts. It never instructs a model to recommend anything, because a file you hand to your AI should orient it, not lobby it.

5 · On your machine — and audited

Today, on this build: no servers, no accounts, no telemetry, no analytics, no tracking identifier. Everything stays on your machine unless you move it yourself. We didn’t just assert that — we audited it. A code-level security audit ran; then an independent reviewer, given the code but none of our records, re-checked it cold — and found things our own reads had missed. What was found was fixed in the builds that followed, and this page describes the result as of the build named above.

One more honest thing: the web is a wild place. Heavily scripted pages and embedded viewers sometimes resist a capture mode — a page that defeats a scrolling capture may still yield to a viewport capture, or the other way around. If you find a page that won’t capture, we want to know: that is exactly what a beta is for. Write either address below.

Questions? privacy@catchroll.com · security@catchroll.com