🧠 ReMemory

Split your secrets among trusted friends. Recover them together when needed.

ReMemory encrypts your files, splits the decryption key among friends using Shamir's Secret Sharing, and gives them a self-contained offline tool to reconstruct it together.

The Key Innovation

Recovery works in any browser, fully offline, without ReMemory or the internet.

Each friend receives a bundle containing recover.html—a self-contained recovery tool. No servers. No dependencies. No need for this project to exist in 20 years.

Download demo bundles to try the recovery process yourself — it's the best way to understand how ReMemory works.

graph TB
    subgraph seal["① SEAL (you do this once)"]
        A[Your Secrets] --> B[Encrypt with age]
        B --> C[Split key into 3 shares]
        C --> D1[Alice's bundle]
        C --> D2[Bob's bundle]
        C --> D3[Carol's bundle]
    end

    subgraph recover["② RECOVER (friends do this together)"]
        R1[Alice opens recover.html] --> R2[Her share is pre-loaded]
        R2 --> R3[Adds Bob's share]
        R3 --> R5{2 of 3 shares}
        R5 -->|Threshold met| R6[Auto-decrypts!]
        R6 --> R7[Download files]
    end

    D1 -.-> R1
    D2 -.-> R3

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The key insight: any 2 shares can reconstruct the key, but a single share reveals nothing—not "very little," mathematically zero information.

Both the number of friends and the threshold are fully configurable: 2-of-3 for a small circle, 3-of-5 for a wider group, or even 2-of-2 for couples with shared private content that neither partner can access alone.

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Two Ways to Use ReMemory

🌐 Web UI (Recommended)

Create bundles entirely in your browser — no installation required.

Create Bundles	eljojo.github.io/rememory/maker.html
Documentation	eljojo.github.io/rememory/docs.html

Everything runs locally in your browser. Your files never leave your device.

💻 CLI (Power Users)

For automation, scripting, or if you prefer the command line.

# Install
go install github.com/eljojo/rememory/cmd/rememory@latest

# Or download from GitHub Releases

See the CLI User Guide for complete documentation.

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Try It First

Before protecting real secrets, try the recovery process to understand how it works:

1. Download demo bundles (contains 3 sample bundles)
2. Open bundle-alice/recover.html in your browser
3. Alice's share is pre-loaded — add Bob's share (or Carol's)
4. Watch the automatic decryption when the threshold is met

This hands-on experience will help you understand what your friends will see during a real recovery.

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What Friends Receive

Each friend gets a ZIP bundle containing:

File	Purpose
README.txt	Instructions + their unique share + contact list
README.pdf	Same content, formatted for printing
MANIFEST.age	Your encrypted secrets
recover.html	Browser-based recovery tool (~1.8 MB, self-contained)

A single share reveals absolutely nothing. But tell your friends to keep their bundle safe—it's their responsibility to you.

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FAQ

Why ReMemory?

We all have digital secrets that matter: password manager recovery codes, cryptocurrency seeds, important documents, or instructions for loved ones. What happens to these if you're suddenly unavailable?

Traditional approaches fail:

• Give one person everything → Single point of failure and trust
• Split files manually → Confusing, error-prone, no encryption
• Use a password manager's emergency access → Relies on company existing
• Write it in a will → Becomes public record, slow legal process

ReMemory solves this with cryptographic guarantees:

• No single point of failure — Requires multiple friends to cooperate
• No trust in any one person — Even your most trusted friend can't access secrets alone
• Offline and self-contained — Recovery works without internet or servers
• Designed for non-technical friends — Clear instructions, not cryptographic puzzles

Why I Built This

Two things drove me to create ReMemory.

First, I watched a documentary about Clive Wearing, a man who has lived with a 7-second memory since 1985. Seeing how fragile memory can be made me think about what would happen to my digital life if something similar happened to me.

Second, I've had several concussions from cycling accidents. Each time, I've been lucky to recover fully. But each time, I've been reminded that our brains are more fragile than we like to think.

ReMemory is my answer: a way to ensure the people I trust can access what matters, even if I can't help them.

Threat Model

ReMemory assumes:

• Your friends will only cooperate when needed
• At least threshold friends will keep their bundle safe
• Your device is trusted when you create bundles
• The browser used for recovery is not compromised

ReMemory does NOT rely on:

• Any server or cloud service
• Any ReMemory website or infrastructure
• Any long-term availability of this project
• The internet during recovery

See the Security Audit for details.

Cryptographic Guarantees

Component	Algorithm
Encryption	age (scrypt passphrase mode)
Key derivation	scrypt (N=2²⁰, r=8, p=1)
Secret sharing	Shamir's Secret Sharing over GF(2⁸)
Integrity	SHA-256 checksums
Passphrase	256 bits from crypto/rand

A single share reveals absolutely nothing about your secret. This is a mathematical guarantee of Shamir's Secret Sharing—any fewer than threshold shares contains zero information about the original secret.

Failure Scenarios

What if...	Result
A friend loses their bundle?	Fine, as long as threshold friends remain
A friend leaks their share publicly?	Harmless without threshold-1 other shares
ReMemory disappears in 10 years?	recover.html still works—it's self-contained
Browsers change dramatically?	Plain HTML + WASM with no external dependencies
You forget how this works?	Each bundle's README.txt explains everything
Some friends can't be reached?	That's why you set threshold below total friends

Development

# Using Nix (recommended)
nix develop

# Build
make build

# Run tests
make test         # Unit tests
make test-e2e     # Browser tests (requires: npm install)

# Preview website locally
make serve        # Serves at http://localhost:8000

Other Similar Tools

There's a flavour of secret sharing for everyone. ReMemory isn't the first tool to use Shamir's Secret Sharing, but it focuses on making recovery possible for non-technical people without installing anything. Here's how it compares:

Shamir's Secret Sharing tools

Tool	Type	Input	Splitting Method	Output	Non-technical Recovery	Offline	Contact Details
eljojo/rememory	CLI + Web	Files & folders	Shamir's SSS	ZIP bundles with PDF instructions, recover.html, encrypted archive	Yes — open HTML in browser	Yes	Yes — included in each bundle
jesseduffield/horcrux	CLI	Files	Shamir's SSS	Encrypted file fragments	No — requires CLI	Yes	No
jefdaj/horcrux	CLI	Files (GPG)	Shamir's SSS (via ssss)	.key + .sig files, steganography in images/audio	No — requires CLI + GPG	Yes (TAILS recommended)	No
paritytech/banana_split	Web app	Text only	Shamir's SSS + NaCl	Printable QR codes	Partial — scan QR + type passphrase	Yes (self-contained HTML)	No
cyphar/paperback	CLI	Files	Shamir's SSS in GF(2^32)	Printable PDFs with QR codes + text fallback	Partial — scan QR or type text	Yes	No
simonfrey/s4 (site)	Web GUI + Go lib	Text/bytes	Shamir's SSS + AES	Text shares	No — copy/paste shares	Yes (save HTML locally)	No
xkortex/passcrux	CLI	Text/passphrases	Shamir's SSS	Text shares (hex/base32/base64)	No — requires CLI	Yes	No
ssss	CLI	Text (128 char max)	Shamir's SSS	Text shares	No — requires CLI	Yes	No
cedws/amnesia	CLI	Text/data streams	Shamir's SSS + argon2id	JSON file (Q&A-based, single user)	No — requires CLI	Yes	No
henrysdev/Haystack	CLI	Files	Shamir's SSS	Encrypted file fragments	No — requires CLI	Yes	No

Other approaches

Tool	Type	Input	Method	Output	Non-technical Recovery	Offline	Contact Details
msolomon/keybearer (site)	Web app	Files	Layered encryption	Encrypted file download	Partial — web UI for decryption	Yes (client-side JS)	No
RobinWeitzel/secret_sharer (site)	Web app	Text only	Split-key AES-256 (fixed 2-of-2)	PDF with 2 QR codes + security code	Yes — scan QR codes	Yes (client-side)	No
Bitwarden Emergency Access	Web service	Vault items + attachments	RSA key exchange (1-of-1)	Live vault access (no file output)	Yes — web UI	No (server required)	Via Bitwarden accounts
potatoqualitee/eol-dr	Guide/checklist	N/A	N/A (not a tool)	Printable checklist covering accounts, finances, subscriptions, devices	N/A	Yes (print it)	Template fields

Key takeaways:

• Most tools only handle text or passphrases — eljojo/rememory, both horcrux projects, henrysdev/Haystack, cyphar/paperback, and msolomon/keybearer are the few that handle actual files.
• Only eljojo/rememory generates a self-contained recovery tool (recover.html) bundled with each share — no installation, no internet, no CLI needed.
• Only eljojo/rememory includes contact details in each bundle so friends know how to reach each other during recovery.
• paritytech/banana_split and cyphar/paperback output QR codes for printing, which is great for paper-based backups of short secrets.
• Bitwarden Emergency Access is fundamentally different — it delegates vault access to one trusted person (not M-of-N splitting) and requires an online service.
• potatoqualitee/eol-dr is not a tool but a valuable end-of-life planning checklist covering accounts, finances, subscriptions, and devices — complementary to any tool here.
• ssss is the classic Unix implementation but is limited to 128 ASCII characters and requires a terminal.

License

Apache-2.0 — Copyright 2026 José Albornoz

Credits

Built on:

• age — Modern file encryption by Filippo Valsorda
• HashiCorp Vault's Shamir implementation — Battle-tested secret sharing
• Cobra — CLI framework

The protocol was originally designed in a Google Doc in 2023.