Šepot — end-to-end encrypted messenger

Initial public release. Anonymous on-device identity (no phone number,
e-mail, or password), Signal-protocol cryptography (X3DH + PQXDH, Double
Ratchet, sealed sender) via libsignal, a metadata-minimizing relay,
group chats, disappearing messages, encrypted local storage, optional
Tor transport, and a UI localized into Czech, English, German, Russian,
and Italian.

Monorepo: Flutter client (app/), Rust relay + wire types (rust/),
protobuf definitions (proto/), self-host deploy (deploy/).

Licensed under AGPL-3.0 with an app-store distribution exception (§7).

THIRD-PARTY-NOTICES.md

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+# Third-party components & license notices
+
+Šepot links third-party components. This file documents their licenses and,
+where relevant, their status with respect to app-store distribution.
+
+The cryptographic core is not implemented by Šepot; it is provided by Signal's
+`libsignal` through a third-party Dart binding. Both are AGPL-3.0, which is why
+their app-store status is documented in detail below.
+
+## Signal `libsignal` (AGPL-3.0)
+
+- **Component:** Signal's Rust `libsignal`, used via FFI behind the
+  `SepotCrypto` facade through the `libsignal` Dart binding on pub.dev.
+- **Copyright:** Signal Messenger, LLC.
+- **License:** GNU Affero General Public License, version 3 (AGPL-3.0).
+  Upstream: <https://github.com/signalapp/libsignal>
+- **App-store distribution status:** The current AGPL Rust `libsignal` does
+  **not** ship with an explicit "app store" additional permission in its
+  LICENSE file. However, Signal has publicly stated that it has no objection
+  to GPL-compliant open-source applications distributing its libraries through
+  the Apple App Store, and it previously added an explicit app-store
+  additional permission to the earlier `libsignal-protocol-c`
+  (<https://signal.org/blog/license-update/>). Precedent: several
+  Signal-derived, GPL/AGPL-licensed messengers (e.g. Session) are distributed
+  on the Apple App Store on this basis.
+
+  Šepot relies on that stated position and, as an AGPL work, keeps its
+  complete corresponding source available under the AGPL through channels
+  without app-store restrictions (this public repository, F-Droid, direct
+  APK). A written clarification for the current Rust `libsignal` has been
+  requested from Signal (tracking: <https://github.com/signalapp/libsignal/issues/684>).
+
+## `libsignal` Dart binding (AGPL-3.0)
+
+- **Component:** the `libsignal` Dart package on pub.dev, which wraps Signal's
+  Rust `libsignal` and ships the precompiled native binaries.
+- **License:** AGPL-3.0.
+- **App-store distribution status:** in a public issue on the binding's
+  repository, its maintainer indicated an intent to add an explicit AGPL §7
+  app-store additional permission covering the binding layer and its
+  `libsignal_frb` crate, conditioned on the application's complete source being
+  publicly available under the AGPL — which this repository provides. That
+  permission, once added, would cover only the binding's own code, not Signal's
+  upstream `libsignal`.
+
+## Šepot's own App Store exception
+
+Šepot's own code carries an additional permission under AGPL section 7 that
+permits app-store distribution (see `LICENSE`). That permission covers only
+the parts whose copyright is held by the Šepot contributors; it does not, and
+cannot, grant permissions on behalf of Signal Messenger, LLC for `libsignal`.