Paul HittandClaude Opus 5 38e31fc5ee A story reaches this account's own devices, so reactions have somewhere to land
Posting sent the story to the audience and saved it locally. Nothing went
to this account's other devices, so a story posted on the phone did not
exist on the tablet at all.

Reactions do go to every device the author has. The other device received
all of them and had no story to attach them to, so they sat in a map
nothing reads and the person watching saw a story drawing no response. The
only way out anybody found was to stop using the second device.

Each posted story is now mirrored to this account as well, carrying the
same story key so one story stays one story across the devices. Best
effort and outside the audience count: an account with one device has
nowhere to send it and that is still a successful post.

On the way in, a story from this account is filed as this account's own,
and only from a proven sender, or an unproven envelope claiming our id
could put a stranger's story on our own strip and show us its reactions.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-09-16 13:57:30 -04:00
2026-08-21 18:22:30 -04:00
2026-09-12 16:14:56 -04:00
2026-08-21 18:22:30 -04:00
2026-08-21 18:22:30 -04:00
2026-08-21 18:22:30 -04:00
2026-08-21 18:22:30 -04:00
2026-09-09 09:30:32 -04:00
2026-09-09 16:58:55 -04:00
2026-09-09 09:30:32 -04:00

Flamenet Messenger. Android

The Android app, and the two libraries under it. The product's site is at https://flamenetmessenger.com.

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: messaging, groups, attachments, voice notes, stories, calls, sealed sender, key transparency and the encrypted vault are built and tested, and a cross-platform round trip against iOS is verified.

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_HOME is 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.
S
Description
Flamenet Messenger for Android — the Kotlin engine, held to the published protocol vectors. No app yet. MIT.
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