FindACase (FAC)

FAC is a single-file encryption app that locks your files into one standard age vault and opens it again — on Windows and Android (Linux/macOS too), fully offline, straight from a USB stick. No installation, no account, no cloud, no internet access at all. The app is one self-contained FindACase.html; the vault it produces is a plain age + tar file (an open standard), so your data stays recoverable even without this tool.

Closed-source, proprietary application. Free to use (including commercially) — not for sale, not modifiable, no reverse-engineering, no redistribution. See LICENSE and DISCLAIMER.

💛 FAC is free. If it keeps your files safe, you can support development with a donation: PayPal paypal.me/FAMarco (@FAMarco). Thank you!

Offline first, private by design

FindACase is built as an offline tool for your own files — it works with the network cable pulled, and that is not a promise but a technical property of the app itself.

• No ads. No account. No subscription. Copy one file to a stick, open it, done.
• No telemetry, no phone-home — no network, by construction: the page ships a strict Content-Security-Policy (default-src 'none', no connect-src, no eval). Everything is inlined into the single HTML file, so the app cannot open any connection, not even to its own local origin.
• Open vault format: an age v1 file (scrypt passphrase or X25519 public-key, ChaCha20-Poly1305 in STREAM mode) wrapping a standard tar archive — see Recovering a vault without FindACase.

Author / copyright: © 2026 Marco Aurelio Fattizzo (@eVersor-HN). This is the official distribution repository — get FindACase only from here: https://github.com/eVersor-HN/FindACase

---

Download & install

1. Open the Releases page and download from the latest release:
   • FindACase.html — the app itself (this is the file the checksum verifies), or
   • FindACase-<version>.zip — the full USB-stick package (app + Windows-Start.cmd and start.sh launchers + README.txt manual + LICENSE / DISCLAIMER / notices).
2. Verify it is the genuine original (see below) before using it.
3. There is nothing to install — copy the file (or the unzipped folder) onto a USB stick or anywhere else and open it. No administrator rights are ever needed.

---

Verify authenticity (SHA-256)

Every official release publishes the SHA-256 checksum of FindACase.html. Comparing the checksum of your download against the published value proves the file is the unmodified original and was not tampered with. (The same repository address and this verification hint are shown inside the app under Help → About.)

v1.0.1 — FindACase.html:

fad0b489b7cae4aed24667d8cda1970f75c3ebfe2a140242026cb5bf6102e4c7

The authoritative value for each release is in that release's notes and in its SHA256SUMS.txt asset.

Check it on Windows:

Get-FileHash .\FindACase.html -Algorithm SHA256

Check it on Linux / macOS / Android (Termux):

sha256sum FindACase.html

The printed hash must match the value above (case-insensitive). If it does not match, do not use the file — it is not the genuine FindACase build.

---

Features

• One vault, open format — all selected files and folders go into one encrypted .age file: age v1 with ChaCha20-Poly1305 in STREAM mode, wrapping a standard tar archive. Truncated or tampered vaults are rejected on extraction, and a Verify button checks a whole vault without writing any files.
• Two ways to lock a vault — a passphrase (scrypt) or a public key (X25519 age1… recipients; the vault opens only with the matching private identity, no password).
• Optional 2-factor — combine the passphrase with a key file; both are then required to open the vault.
• Selectable protection level — scrypt work factor 18 / 19 / 20 (≈ 256 MB / 512 MB / 1 GB RAM to open), so you choose the brute-force cost.
• Built-in generators — strong random passwords (selectable length, entropy shown), key files, and X25519 key pairs, all generated locally.
• Streams everything, constant memory — tar and age both stream, so multi-GB vaults work without filling RAM (verified: a 1 GB vault round-trips at ~115 MB peak RSS).
• Bilingual UI — German / English, switchable top-right; full guide, FAQ and About are built into the app (Help button).
• USB-stick launchers — Windows-Start.cmd (Windows) and start.sh (Linux/macOS) start a tiny local 127.0.0.1 server (no admin, no internet, DNS-rebinding-proof Host-header check, serves only FindACase.html) and open the app over localhost, which unlocks the File System Access API for direct disk streaming.
• Runs anywhere — any modern browser; no dependencies bundled or required for quick use.

How to run it

• Windows, full streaming (recommended for large vaults): double-click Windows-Start.cmd from the release zip. It uses the PowerShell that ships with Windows — nothing to install.
• Linux / macOS: run start.sh (prefers PowerShell 7 pwsh, falls back to Python 3). Direct disk streaming then works in Chromium browsers (Chrome, Edge, Brave); Firefox/Safari automatically fall back to the in-memory path.
• Quick use / Android: open FindACase.html directly in your browser (file://). Reading and decrypting still stream; created/extracted files go through memory, so prefer the launcher for very large vaults on desktop.

Recovering a vault without FindACase

The vault format is deliberately not proprietary. If this tool ever disappears, any vault still opens with the official open-source age CLI (or rage) plus tar — tar ships with Windows 10/11:

age -d -o vault.tar vault.age    # prompts for the passphrase
tar xf vault.tar                 # (public-key vaults: age -d -i identity.txt ...)

The __tresor_manifest__.json entry inside is just the vault's table of contents.

Important — the encryption is real: if you lose your password (or key file / private identity) there is no recovery, by anyone. Keep passwords and backups safe and separate from the vault, and only open vaults on devices you trust.

System requirements

• Any modern browser. On desktop, a Chromium-based browser (Chrome, Edge, Brave) enables direct disk streaming via the launcher; Firefox/Safari use the in-memory path.
• Windows 10 / 11 for Windows-Start.cmd (built-in PowerShell, no admin rights); Linux / macOS need pwsh or Python 3 for start.sh. Android needs no launcher.

License (summary)

FindACase is proprietary, closed-source software under the FindACase EULA (full text in LICENSE):

• Permitted: free use for any purpose, private and commercial (companies included), plus the exact copies needed to install, run, back up and deploy it internally (USB sticks, company devices, intranet).
• Not permitted: modifying or adapting it, reverse engineering / decompiling / disassembling, selling, renting, sublicensing, or redistributing it to third parties — except where applicable mandatory law provides otherwise (see LICENSE, Section 3).

It bundles open-source crypto libraries under their own licenses — typage (age-encryption, BSD-3-Clause) and the noble cryptography libraries (MIT) — in minified/obfuscated form with their copyright notices preserved. Full details and texts: THIRD-PARTY-NOTICES.txt.

No warranty — see DISCLAIMER.md.

---

© 2026 Marco Aurelio Fattizzo · FindACase · proprietary, all rights reserved