Phase 6 of docs/frost-batch-signing.md. 361 jvmTest and 227 testDebugUnitTest pass. ## Inbound path (SignedGroupKeyStateTest) Both drive the manager with a hand-built inner event rather than one the other device queued, which is the only way to be a faulty or dishonest member in this harness. - A one-value nonce offered for a three-item batch does not count towards the threshold: the coordinator never reaches a signer set. The length check is all that stands between a batch and a signer whose contribution lines up against the wrong messages, so truncating or padding would produce partial signatures aggregated against events nobody agreed to. The test then pumps the real nonce and the batch completes -- it is a stall, not damage, which is FrostSignerMessage's composite key doing its job. - A second proposal under the session's own id changes neither its event ids nor its seeds. Every seed is already committed to its item's message; a different batch under the same id would have those seeds produce a second partial signature over a second message, which is how a share is extracted. ## Real FROST, no database (FrostSigningRoundTest) - A k=3 batch from one signer set, all three verifying against the room's key -- the manager's shape with the database taken out of the way. - Item 0's signature does not verify against item 1. Signing three events in lockstep must not make any of them interchangeable. - Both halves of the no-shared-nonce property, because either alone is enough to be relied on by accident: SecretNonce.generate mixes the message in, so one seed under two messages already gives two nonces -- and the manager mints distinct seeds regardless. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
mantra docs
Notes on the parts of this app whose behaviour is not recoverable by reading the code alone — where the reasoning lives in a protocol, a failure mode that is silent, or a decision that looked arbitrary and was not.
| document | covers |
|---|---|
| shared-key-ceremony.md | ChillDKG over NIP-17: the rounds, the approval gates, the chat transcript, participant ordering |
| shared-key-derivation.md | deriving further keys from the group's threshold key with FROST tweaks — why not BIP32, why no chain code, and the one rule that must not be broken |
| frost-batch-signing.md | signing several events in one ceremony — why one nonce can never cover two messages, and the phased schema, wire and UI work that follows from it |
| marmot-membership.md | how members join an MLS group, and the epoch race that makes a missing member look like a successful invite |
| marmot-direct-messages.md | a one-to-one message inside a group as a stock NIP-59 gift wrap — what its MIP-03 carve-out costs, why the sender cannot read their own, and the one query that would broadcast it |
| mls-skipped-keys.md | why a group event that arrives a moment late is dropped for good, which flows trigger it, the quartz fix, and the partial mitigation in this app |
| long-running-sync.md | the chat subscriptions that stay open instead of pulling once per screen — why the request queue could not simply hold one, and how the group filter follows the room list |
| dead-code.md | code in the sync and relay stack that nothing calls, why each piece is still there, and which of it is a bug rather than a leftover |
| jvm-target.md | what desktop support cost, phased — why the native chain was already done, why an empty source set in our phoenix fork was the real blocker, and why DAO tests need none of it |
Start with the ceremony if you are new to this area; the Marmot notes all assume it. Read the skipped-keys note before debugging any "the other device never got it" report — it is silent, and it looks like every other kind of delivery failure. The sync note stands alone, and the dead-code inventory reads as a follow-up to it. The batch-signing note is a plan rather than a description of what is there: read it after the derivation note, whose one rule is the same one it is built around. The jvm-target note is unrelated to all of them: it is a build and packaging story.