MERKI.A fresh keyfor every move.
MERKI is a post-quantum smart wallet for Robinhood Chain. Same address. Fresh keys. Post-quantum signatures. Every operation is signed by a one-time key built from hash chains, and that key is spent the moment the chain accepts it.
Contract address coming soon- Hash-based one-time keys
- ERC-4337 EntryPoint v0.7
- No admin key in the contracts
Layout sample · not your account
The wallet runs in practice mode until the keyhold contracts are deployed: real phrase, real keys, real signatures, no funds moved.
01Built for holdings you keep
Keep the long-term stash apart. Guard it with hashes.
Most people already have a wallet for trading. MERKI is the other one: an account for the coins and stock tokens you plan to hold for years, authorised by a signature that does not rely on elliptic curves.
- 01
Your phrase never leaves the device
Your browser makes the 24-word phrase itself and keeps it there, locked with a password you pick. The site's server never receives it, and neither does the wallet you connect to pay gas. Lose the browser, and the phrase is how you get the keys back.
- 02
One address, a moving key
Your keyhold address is fixed by its first two keys and is known before anything is deployed. Every accepted operation swaps the stored key for the next one in your line, so people can keep paying the same address while the key behind it keeps changing.
- 03
Hash chains, not curves
Each key is 67 short chains of Keccak-256. Signing reveals a point on every chain; checking means hashing forward to the end. No elliptic-curve math is involved in authorising your account, and that is the part a quantum computer is expected to break.
02The key moves, the address stays
Sign once. Then step forward.
A one-time key may sign exactly one message. So every signature also names the key that comes after it, and the keyhold stores that next key while it accepts the current one. Try it on the right: the demo runs the same signer the wallet uses and the same check the contract runs.
Inside the signature- Chains per key
- 67
- Signature
- 2,209 B
- Verifier gas
- ~106k
Derive, sign, verify, retire
Press the button: this tab makes a throwaway secret, derives key #0, signs a random operation, checks the signature the way the keyhold contract does and moves on to key #1.
03Later, beside every tab
The web wallet first. A side panel next.
Today the keyhold lives in the web wallet on this site. A browser extension that keeps it beside any page, with readable approvals for each transaction, is planned and not released. The preview below is a design, not a download.
What the extension will doA site asks for a transfer
The panel shows the full recipient, the amount and which key will sign. Nothing moves until you approve it there.
Approve operation
- Site
- example.app
- To
- 0x9a…41c7 (full address shown)
- Amount
- 0.05 ETH
- Signs with
- main key #12
- Then stores
- key #13
Design preview of a planned extension · example values, not account data
Read before you approve
Every request will show the full recipient, the amount and the key that signs it.
Transactions only
A one-time key cannot safely sign off-chain messages, so site logins and permit signatures are out.
One signer per phrase
Use either the web wallet or the extension for a phrase, never both at once.
04Plain about the limits
What it protects. What it leaves alone.
Post-quantum, in MERKI, describes one thing: how your keyhold decides that an operation really comes from you. The chain, your device, the submitting wallet and your activity get no such protection, and nothing becomes private. This is a prototype; keep amounts you can afford to lose.
Covered by the keyhold
- Account authorisation
- Hash-based one-time signatures checked by your keyhold contract through the ERC-4337 EntryPoint v0.7.
- Key reuse
- A key that has signed is retired in the same step that accepts its signature, even when the operation's calls revert.
- Replays
- The EntryPoint nonce stops resubmission; a copied signature fails on any other operation.
Not covered
- Robinhood Chain itself
- Consensus and the chain's own infrastructure still use classical cryptography.
- The submitting wallet
- Its ordinary signature pays the gas. It could delay your operation, but it cannot change or forge it.
- Your device and connection
- Malware on an unlocked browser can read the phrase. RPC and TLS sit outside this project.
- Privacy
- Operations are public transactions: amounts, recipients and timing are visible to everyone.
Measured cost
182,501 gas for an ETH transfer inside the EntryPoint in our Foundry tests, 312,652 when the same operation also deploys the keyhold.
How it was measuredCompatibility
On-chain transactions of any kind: transfers, swaps, contract calls. Off-chain signatures (logins, permits, ERC-1271) are refused by design.
Network
Robinhood Chain mainnet, chain id 4663, using the standard EntryPoint v0.7 already deployed there. Keys are bound to the chain id, so a phrase gives other keys elsewhere.
05For the people who check
Small enough to read in an evening.
Three Solidity contracts, one browser signer, one deployment check. The verifier and the signer are tested against each other byte for byte, and the keyhold is tested against the real EntryPoint on a fork of Robinhood Chain.
01What is MERKI?
MERKI is an experimental smart wallet on Robinhood Chain, and only you hold its keys. Your account is a small contract, a keyhold, that accepts hash-based one-time signatures instead of the usual elliptic-curve signature. It is meant as a long-term vault next to the wallet you trade with every day.
02How does MERKI work?
Your recovery phrase stays in your browser and produces an endless line of one-time keys. Every operation carries a signature from the key whose turn it is, and that signature names its successor. The keyhold checks the signature, retires the key that signed and stores the next key, all in the same step. The address stays put while the signing key keeps moving.
03What does post-quantum mean here?
Only this: the signature that authorises your account is built from Keccak-256 hash chains, not from the elliptic-curve math a big enough quantum machine might break. The chain's own consensus, the wallet that submits your transaction, your device, your internet connection and your privacy are outside that claim.
04Will my address move when a key is retired?
No. The address is fixed by your first two keys and is known before the keyhold exists, so you can receive funds first. Every accepted operation replaces the stored key, and the address stays the same.
05Which network is MERKI on?
Robinhood Chain mainnet, chain id 4663. The keyhold uses the standard ERC-4337 EntryPoint v0.7 that is already deployed there; the site checks its code before any operation.
06How do I buy $MERKI?
The $MERKI contract address is published on this site and on X @merki at launch. Until it appears here, there is nothing official to buy; a token that uses the name before then is not ours. You never need the token to use the wallet.
07What if an operation gets stuck?
Signing it again would use the same one-time key twice, which is exactly what must never happen. Instead a key from a separate rescue line authorises one substitute that reuses the stuck nonce. Only one of the two can ever be included, and afterwards the keyhold advances both lines.
08Are my transactions private?
No. Every keyhold operation is a normal public transaction on Robinhood Chain: amounts, recipients and timing are visible to anyone. MERKI changes how your account is authorised, not what the chain shows.
Same address. A different key on every send.
Make a phrase, look at your first keys, sign a practice operation and watch the key move on. It takes about a minute and moves no funds.