Content generated by an LLM with human direction.

Security: your files stay yours

Eigendeck is careful with two things: the files on your computer (a deck can't read them behind your back) and what a deck's demos can do (they're boxed in, and they can't use the internet unless you allow it). This page covers both.

The rule

A .eigendeck is a file people email and share, like a PowerPoint or a Beamer .tex. Eigendeck treats a deck you received differently from one you made:

• A deck can always show its content. Everything a deck carries is embedded inside it, so any deck opens fully and displays everything — nothing is hidden or blocked.
• A deck can only read live files off your computer if you trust it. Linking a slide to a file on disk (so it updates when you edit that file) is a real feature — but a deck you received can't do it until you say so, and you can always see exactly which files it wants.

Decks you create are trusted. Decks you receive are not — until you decide.

Why this exists

An image you paste or insert is embedded — a copy lives in the deck. But a deck can also link to a file that stays on disk and is re-read as it changes. That convenience is also a risk: a malicious deck could link to one of your private files (an SSH key, a credentials file), get your computer to read it in, and — because the file's contents are now inside the deck — carry it out the next time you share the deck. The person you send it to is the leak.

So Eigendeck draws the line at the read: it simply won't read a file off your disk that you didn't approve. Get that right and there's nothing to leak, no matter who you send the deck to.

Two consequences you'll feel:

• If you never link external files, you'll never see any of this. Insert or paste your images (they embed) and there is nothing to watch and no prompts — ever. This is most people.
• Eigendeck can only ever watch presentation files. Images, PDFs, videos, notebooks, and demos — the things a slide is made of. A deck can never get you to watch your SSH key or a credentials file; those aren't presentation content, so they're refused outright, before you're even asked.

How it respects your data

• Your source files are never modified. Watching reads them; it never writes them. (Notebooks work the same way — see Notebooks.)
• Your content never leaves on its own. The only way your files or slides go out is you sharing the deck. (Interactive demos can use the internet — but only if you allow it and only for the sites they name; see Demos and the internet below.)
• Exported HTML has no live links. Everything is baked in as static content, so an exported deck carries no connection back to your disk.

How it respects your time

Security you have to click through constantly is security you stop reading — so Eigendeck keeps out of your way:

• No pop-ups when you open a deck. A received deck just opens and shows its content; live-watching is simply off until you choose to turn it on.
• You approve once, and it sticks. When you trust a deck you review its linked files once; after that they just work.
• Trust fades gently, not abruptly. A deck you keep using stays trusted. One you haven't opened in about a month asks you to re-confirm — a single click that restores everything, surfaced as a quiet notice, never a blocking dialog.

The Security Panel

When a deck links to external files, you manage them in the Security Panel — a window that lists, for the deck:

• every external file it links to, and where each one is used (which slide / element);
• the real file each link points to (resolved in full, so a link can't disguise where it actually goes);
• whether each is watched, awaiting your approval, or refused (not a presentation file).

There are two steps, and they're separate on purpose. First you Trust this deck — a one-time decision that unlocks watching and, by itself, reads nothing. Then you approve the files you actually want watched — one at a time, or a whole folder at once. (There's no single "trust everything" button; trusting the deck and choosing its files are deliberately two decisions.) Refused files are shown so you understand what a deck tried to reach, but they can't be approved. You can also see a single file's status right in its inspector when you select that element on the canvas.

Working with a deck someone sent you

1. Open it. It displays completely — every image, demo, and notebook. Nothing is hidden.
2. If you want its linked files to stay live (update as they change on disk), open the Security Panel, click Trust this deck, then approve the files (or whole folders) you recognise. Until then it shows the embedded copies it came with.
3. If a link points somewhere you don't expect, don't approve it — the panel shows you the real destination precisely so you can catch that.
4. Later, if it asks you to re-confirm (about a month on), that's the trust timer; one click brings it back.

If you'd rather not deal with live files at all, turn off file-watching globally in Settings — then decks are always self-contained copies and none of this appears.

Demos and the internet

Some slides carry demos — small interactive widgets like charts, simulations, and graphs. Two things to know:

• A demo can't touch your files or the rest of your computer. It runs boxed in (a sandbox), the same way a web page in your browser can't reach your files. This holds even for a deck you haven't trusted.
• A demo can use the internet — but only if you allow it, and only for the sites it names. Some demos fetch live data or load a chart library from the web. A demo has to declare which sites it uses (and why); it can reach only those, and nothing else. A demo that declares nothing stays offline.

You're in control in three places, from broad to specific:

• Everywhere — Settings → Security has a master switch to turn demo internet off for every deck.
• Per deck — a deck's Security window has an Internet tab with one switch to keep this deck's demos offline. Good for a deck from someone you don't fully trust.
• Per demo — that same Internet tab lists each demo that goes online, the exact sites it uses, and what for — so you can switch off just the one you don't like.

Turning the internet off doesn't break a demo; it just runs offline. It only means the demo can't fetch live data or "phone home" — for example, quietly recording when and where you open the deck. When something is switched off higher up, the controls below it grey out, so you can always see why a demo is offline.

Related

• Watched assets — how linking + watching works day to day.
• Sync and link — relating elements across slides (a different meaning of "link").
• Notebooks — recording and editing without touching your source.