01
.lockbox container
A binary file format that wraps any payload in AES-256-GCM with a wrap key the operator can destroy. Spec is open. Reference encoder / decoder ships in TypeScript.
Product · Capsule
A sealed file with a kill switch.
Capsule is the standalone file-level wrapper. Drop any document and it becomes a .lockbox: encrypted on disk, openable only with a live key, controlled by a kill switch you hold. The same Capsule technology powers Continuum, but Capsule itself is free, public and built for the file you have in your hand right now.
Inside Capsule
Four pieces. One sealed file.
02
In-browser viewer
A PWA viewer that decrypts on the recipient device, renders PDF / Excel / Word / PowerPoint / images, and wipes plaintext when the heartbeat returns burned. No install. iOS Safari and Android Chrome supported.
03
Recipient self-claim
Before the key is released, the recipient states who they are: name, email, optional phone. The claim is signed into the chain and woven into every render as a forensic watermark.
04
Public chain verifier
A no-auth web page that drag-and-drops any evidence pack and verifies the Ed25519 signature against /api/chain/pubkey. Five lines of code in any language.
Lifecycle
The four moments of every Capsule.
- 01Issue. Drop a file into the operator screen. Server seals AES-256-GCM, generates a .lockbox blob and a separate consent URL. Two artefacts, one chain root.
- 02Claim. Recipient taps the consent URL. States their name. The claim is signed in. Their stated identity becomes part of every future render.
- 03Open.Plaintext lives in process memory only. The recipient's name is woven diagonally across every preview, including screenshots.
- 04Burn. Operator clicks Burn. The wrap key is destroyed. Every encrypted copy on every device on Earth becomes mathematically indistinguishable from random data.
Capsule and Continuum
Same wrapper. Two control planes.
Capsule is the file. Continuum is the org. Capsule on its own is enough for one freelancer protecting one attachment. Continuum is what you upgrade to when you have 50 senders, multiple tenants, AIP labels, an SSO requirement and a regulator on the other end of an audit. The chain is the same. The wrapper is the same. The control plane around them changes.
Capsule sits inside Continuum
Every Continuum tenant's files are Capsules. Every Capsule's chain is verifiable in the same public ledger.
Continuum · for the org
Capsule · for the file
Ed25519 chain · for everyone
Try it now
Open one .lockbox. See the chain build.
The viewer runs in any modern browser. No install, no account, no contract. The receipt you generate is verifiable by anyone with a 32-byte public key.