`poll` was at 0%. The tests that cover it — the Live* suites — are opt-in via FN_LIVE_FLEET and skip in an ordinary run, so the single most important path in the client contributed nothing to a normal build. That is worse than having no test, because the file listing says otherwise. Nothing here is stubbed below the transport: the peer is a real DeviceIdentity, the envelopes are real ciphertext from a real ratchet, and only the relay's HTTP is a mock. A decrypt that succeeds here succeeded for the same reason it does in the field. The three-chain rule gets the test its comment asks for. This used to be `existingSession(fromDevice) ?: respond(...)`, which reads as a fallback and is not one: with a stored session it was the only thing tried, decrypt threw for a peer on a different chain, and the catch swallowed it. That happens whenever both sides run X3DH before either has processed the other's prekey — two people opening the same chat at once, which is ordinary — so the test stores one chain and then has the peer start a fresh one. The C1 receive-side gate is asserted from both sides: a handshake offering an unpinned key while claiming a pinned contact is dropped, and the same handshake from the pinned key is accepted. Without the gate, anyone could hand us a session with their own key and every later message would render as that contact. Also that one unreadable envelope does not discard the rest of the page AND that the watermark still passes it, or a single corrupt message is retried for ever and the inbox never drains; and that a failed poll surfaces rather than being reported as an empty inbox, since "no new messages" and "we could not ask" are different states. ⚠️ One test needed two distinct user ids: two identities claiming one user is exactly what C1 refuses, so writing it with the default sender makes the second message vanish — correctly, and confusingly. Conversations 25.4% -> 43.0%, client 63.2% -> 68.9% lines. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Flamenet Messenger — Android
The Android app, and the two libraries under it.
engine/ the protocol: X3DH, Double Ratchet, sealed sender, safety numbers,
key transparency. Plain Kotlin/JVM — no Android in it at all.
client/ the relay transport: HTTP, auth, the §8 routes.
app/ the Compose app.
interop/ the cross-engine driver; not shipped.
engine and client are deliberately plain JVM libraries. The protocol has
nothing to do with Android, and keeping it off the platform means their tests
run anywhere a JVM does — no SDK, no emulator, no device, which is also what
lets them gate in CI on Linux:
./gradlew :engine:test :client:test
The app's own unit tests need the Android SDK but still no emulator (Robolectric):
./gradlew :app:testDebugUnitTest
Where it stands
PARITY.md is the definition of done for this app — read that, not this. Every row there names the iOS file it came from so it can be re-checked rather than trusted. Headlines as of 2026-08-28: messaging, groups, attachments, voice notes, stories, calls, sealed sender, key transparency and the encrypted vault are built and tested; a cross-platform round trip against iOS was verified on 2026-08-26.
⚠️ This file said "Nothing here is an app yet" until 2026-08-28, above a tree containing the finished app — the README described the repository as it was when the engine landed and nothing updated it as the app grew around it. If a claim here ever disagrees with PARITY.md or with the tree, believe those, and fix this.
Why the engine came first, and is held to the vectors
An Android client needs the protocol implemented a third time, and the third
implementation is the one that finds the places where the specification says
less than the two existing engines quietly agreed on — but only if it is
written against the spec and the published vectors rather than against a
reading of our own Swift and JavaScript. So the engine is held to
test/vectors/protocol-v1.json in
flamenet-e2e — the same file the
other two engines are checked against, read from that repository rather than
copied here, because a copied vector file drifts and a drifting vector file
stops being a check. PublishedVectorsTest looks for it beside this checkout
and fails loudly if it cannot find it; FLAMENET_VECTORS overrides the search.
Two implementations that agree may both be wrong in the same way, especially when one was written while reading the other. The audit-path ordering in §19 is the worked example: a top-down reading of a bottom-up path produces the correct root for every left-spine index, so it passes any test that only checks index 0. The vector file pins a right-descending index for that reason, and the Kotlin tests assert both that the published path verifies and that the same path reversed does not.
If this engine ever disagrees with the file, the interesting question is which of the three is wrong — not this one by default.
Contributing and security
- CONTRIBUTING.md — building (JDK 21,
JAVA_HOMEis not optional on a Mac), the test gate, and the platform traps that cost an hour each. - PARITY.md — what iOS does, what this does, and what is left. It is the definition of done for this app.
- SECURITY.md — threat model and where to send a vulnerability report. Not an issue tracker matter: security@flamenetmessenger.com.