Paul HittandClaude Opus 5
e07660559c
The iOS app could not sign up against a Swift relay at all. Sign-up died on a bare "Server returned HTTP 404." with nothing pointing at the cause. The cause: the relay served its route index under BOTH `api` and a legacy prefix, while serving the actual routes only under `api`. The app settles its REST prefix by probing for that index and keeping the first prefix that answers -- so it adopted the legacy prefix, and every call 404'd. ⚠️ This was supposed to have been fixed yesterday, and was not. `f5614ab` (Aug 21, "Serve the four routes the app was calling into a 404") is what INTRODUCED the two-prefix index loop; it was the cause, not the cure. The rule got written down and the code change never landed. My own notes asserted a fix that no branch contained. Believe grep. The rule, which is more general than this bug: **serve a discovery document only where the things it describes exist.** A document listing routes a prefix does not serve is worse than no document, because it is believed. Fixed in three places, because one was not enough: - the relay serves the index only under `api`; - the client probes only `api` -- there is one prefix, and probing for others only creates ways to be wrong; - the index no longer advertises routes that are not mounted. And the purge the owner asked for: no `WordPress`, `wp-json`, `wp/v2`, `wp-admin`, `wp-login`, `wp_` or `wp-cron` anywhere in the relay, the iOS app, the Android app or the tests. `/api/wp/v2/users/me` is now `/api/flamenet/v1/messenger/me`; the user lookup moves alongside it; the dead `ajaxURL` and the two error cases only a web login form could produce are gone. ⚠️ Recorded because it cost time: the deployed relay source on the box is NOT in any branch. It carries multi-homing `envelope_id` work that exists nowhere in git, so copying local files over it broke the build. Restored from the prod tree, then patched in place. That divergence needs closing. Adds CrossPlatformUITests (iOS) and CrossPlatformTest (Android) -- each driven by arguments so the two platforms can be interleaved from a shell, because two iOS accounts in one simulator prove only that the app agrees with itself. With this, item 5 is done: a message typed in the iOS app arrived and rendered in the Android app, through relay1, end-to-end encrypted. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Flamenet Messenger — Android
Nothing here is an app yet. This is the engine, and it is deliberately first.
An Android client needs the protocol implemented a third time. That 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 comes first, it is a
plain Kotlin/JVM library with no Android in it at all, and it is held to
engine/test/vectors/protocol-v1.json — the same file the other two engines
are checked against, read from that one location rather than copied here.
./gradlew :engine:test
No Android SDK, no emulator, no device. It runs anywhere a JVM does, which is also what lets it run in CI on Linux.
What the engine covers today
| Area | Spec | State |
|---|---|---|
| Safety numbers | §7 | Done — fingerprints and conversation ordering match the published vectors |
| Key transparency verification | §19 | Done — RFC 6962 leaf/node hashing, unbalanced split, bottom-up audit paths |
| Byte helpers | — | Unsigned comparison, constant-time equality |
What it does not cover
Listed rather than left to be discovered, because a table of green ticks with the hard parts quietly missing is worse than no table:
| Area | Spec | State |
|---|---|---|
| X25519 / Ed25519 | §3 | Not started — needs a provider that works on both JVM and Android |
| X3DH key agreement | §4 | Not started |
| Double Ratchet | §6 | Not started |
| Sealed sender | §12 | Not started |
| ML-KEM-768 hybrid | §11 | Not started |
| ML-DSA-65 identities | §20 | Not started |
| Relay client | §8 | Not started |
| The app itself | — | Not started |
Until those exist, Android is honestly marked "not started" on the website, and a conversation gets the protocol's guarantees only when both ends are iOS.
Why the vectors matter more than the code
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.