Just Connect Here – what the app is built on
Just Connect Here itself is not an open-source project. But the parts that matter in a messenger – the protocol, the encryption, the server – are: open to inspection, reviewed by many and in use for years. We did not invent our own where the proven thing is better.
This page names those building blocks. You will find the full licence texts in the app under Settings → Open Source Licenses.
| Building block | What for | Licence |
|---|---|---|
| Matrix | The open protocol that carries the messages — not home-grown, but a standard anyone can read. | open standard |
| matrix-rust-sdk | The app’s Matrix client library, written in Rust. | Apache-2.0 |
| vodozemac | The end-to-end encryption (Olm and Megolm). | Apache-2.0 |
| Flutter | The user interface — one code base for iPhone, Android, Mac and Windows. | BSD-3-Clause |
| LiveKit | Calls and group video, on our own server. | Apache-2.0 |
| SQLCipher | The encrypted database on your device. | BSD-3-Clause |
| Building block | What for | Licence |
|---|---|---|
| Synapse | The Matrix server. | AGPL-3.0 |
| PostgreSQL | The server’s database. | PostgreSQL Licence |
| nginx | Accepts all connections and encrypts transport. | BSD-2-Clause |
| LiveKit Server | Relays calls and video. | Apache-2.0 |
| coturn | Helps calls get through routers and firewalls. | BSD-3-Clause |
| ntfy | Delivers notifications — without Google. | Apache-2.0 / GPL-2.0 |
| fail2ban | Locks out attackers. | GPL-2.0 |
The app’s direct dependencies – with the version shipped in the current release. This list is generated from the source code, not maintained by hand.
| Package | Version | Licence |
|---|---|---|
| add_2_calendar | 3.0.1 | MIT |
| app_links | 6.4.1 | Apache-2.0 |
| archive | 4.0.9 | MIT |
| cached_network_image | 3.4.1 | MIT |
| crop_your_image | 2.0.0 | Apache-2.0 |
| crypto | 3.0.7 | BSD-3-Clause |
| cupertino_icons | 1.0.8 | MIT |
| device_info_plus | 11.5.0 | BSD-3-Clause |
| emoji_picker_flutter | 4.4.0 | MIT |
| encrypt | 5.0.3 | BSD-3-Clause |
| file_picker | 8.3.7 | MIT |
| fl_chart | 0.70.2 | MIT |
| flutter_foreground_task | 10.0.0 | MIT |
| flutter_local_notifications | 18.0.1 | BSD-3-Clause |
| flutter_quill | 11.5.0 | MIT |
| flutter_secure_storage | 9.2.4 | BSD-3-Clause |
| flutter_webrtc | MIT | |
| gal | 2.3.2 | BSD-3-Clause |
| go_router | 14.8.1 | BSD-3-Clause |
| http | 1.6.0 | BSD-3-Clause |
| image | 4.8.0 | MIT |
| image_picker | 1.2.1 | Apache-2.0 |
| in_app_purchase | 3.3.0 | BSD-3-Clause |
| intl | 0.20.2 | BSD-3-Clause |
| just_audio | 0.9.46 | Apache-2.0 |
| just_audio_windows | 0.2.3 | MIT |
| livekit_client | 2.4.1 | Apache-2.0 |
| local_auth | 2.3.0 | BSD-3-Clause |
| lottie | 3.3.2 | MIT |
| mime | 2.0.0 | BSD-3-Clause |
| mobile_scanner | 7.2.0 | BSD-3-Clause |
| open_filex | 4.7.0 | BSD-3-Clause |
| package_info_plus | 9.0.0 | BSD-3-Clause |
| passkeys | 2.19.0 | BSD-3-Clause |
| path_provider | 2.1.5 | BSD-3-Clause |
| 3.12.0 | Apache-2.0 | |
| pointycastle | 3.9.1 | MIT |
| provider | 6.1.5+1 | MIT |
| qr_flutter | 4.1.0 | BSD-3-Clause |
| receive_sharing_intent | 1.8.1 | Apache-2.0 |
| record | 6.2.0 | BSD-3-Clause |
| share_plus | 10.1.4 | BSD-3-Clause |
| shared_preferences | 2.5.4 | BSD-3-Clause |
| sign_in_with_apple | 6.1.4 | MIT |
| sqflite_sqlcipher | 3.4.0 | MIT |
| super_clipboard | 0.9.1 | MIT |
| super_drag_and_drop | 0.9.1 | MIT |
| timezone | 0.9.4 | BSD-2-Clause |
| url_launcher | 6.3.2 | BSD-3-Clause |
| uuid | 4.5.3 | MIT |
| video_compress | 3.1.4 | MIT |
| video_player | 2.11.1 | BSD-3-Clause |
| wakelock_plus | 1.5.1 | BSD-3-Clause |
| webrtc_interface | 1.5.1 | MIT |
| workmanager | 0.9.0+3 | MIT |
| Package | Version | Licence |
|---|---|---|
| anyhow | 1.0.86 | MIT or Apache-2.0 |
| eyeball | 0.8.8 | MPL-2.0 |
| flutter_rust_bridge | 2.11.1 | MIT |
| futures-util | 0.3.33 | MIT or Apache-2.0 |
| matrix-sdk | 0.18.0 | Apache-2.0 |
| matrix-sdk-base | 0.18.0 | Apache-2.0 |
| matrix-sdk-crypto | 0.18.0 | Apache-2.0 |
| matrix-sdk-sqlite | 0.18.0 | Apache-2.0 |
| reqwest | 0.13.4 | MIT or Apache-2.0 |
| serde_json | 1.0.151 | MIT or Apache-2.0 |
| tokio | 1.53.1 | MIT |
| vodozemac | 0.10.0 | Apache-2.0 |
Thank you to everyone who maintains these projects.
As of: September 2026
Just