Licences and third-party notices
Last updated 30 August 2026.
Tessera is proprietary software. It is built on components that are not, and several of their licences require that this page exists. The complete licence texts are installed alongside the application; this page is the public copy.
Tessera
© 2026 Studio Heino. All rights reserved. Your rights to use it are set out in the Terms of Use.
Qt
Tessera is built with the Qt framework and is distributed under a commercial Qt licence. Because the commercial licence rather than the LGPL is used, the obligations that would otherwise attach to LGPL distribution — the written offer of object code for relinking, in particular — do not apply to the Qt modules themselves.
Qt is a trademark of The Qt Company Ltd. Modules used include Qt Quick, Qt Quick Controls, Qt Quick 3D, Qt Multimedia, Qt SVG, Qt WebSockets and Qt WebEngine.
FFmpeg
Video and audio playback uses FFmpeg, which is licensed under the GNU Lesser General Public License version 2.1 or later. FFmpeg is linked dynamically and is shipped as separate library files, which is what permits its use in a proprietary application under that licence.
In accordance with the LGPL:
- the full text of the LGPL v2.1 is included with the installed application;
- the FFmpeg libraries are not modified from their upstream builds;
- you are entitled to obtain the corresponding source code for the version shipped, and to relink the application against a modified version of the library. Write to hello@studioheino.com and it will be provided. Because the libraries are shipped as separate dynamic libraries, relinking requires only replacing those files.
FFmpeg is a trademark of Fabrice Bellard, originator of the FFmpeg project. State the exact FFmpeg version shipped, and keep it in step with the build — the LGPL source offer is for the version you actually distributed.
Media format patents
Some media formats are covered by patents that are licensed separately from the software that implements them. A licence to the software is not a licence to the patents.
| Recommended — royalty-free | Patent-encumbered |
|---|---|
| Video: VP8, VP9 (WebM), AV1, Theora | Video: H.264/AVC, H.265/HEVC |
| Audio: Opus, Vorbis, FLAC, MP3, PCM/WAV | Audio: AAC |
Tessera's file pickers list the royalty-free formats first, and those are the formats officially supported. Playback of other formats is best-effort and is not a representation that any patent licence is granted. If you need to use a patent-encumbered format in a commercial setting, obtaining the necessary licence from the relevant pool is your responsibility, as stated in section 9 of the Terms of Use.
The collaboration server
The reference tessera/1 server is a separate program. It is written in Go and uses:
| Component | Licence |
|---|---|
The Go standard library and golang.org/x packages | BSD 3-Clause |
github.com/go-chi/chi | MIT |
github.com/coder/websocket | ISC |
github.com/golang-jwt/jwt | MIT |
github.com/google/uuid | BSD 3-Clause |
github.com/jackc/pgx | MIT |
github.com/redis/go-redis | BSD 2-Clause |
| PostgreSQL | PostgreSQL Licence |
Decide and state the licence the reference server itself is published under. If it is intended to be self-hosted by users, an open-source licence is the option that makes that a right rather than a permission — and the protocol specification is published separately in any case.
This website
The site is a Go program using only the standard library. It serves no third-party code and embeds no third-party assets. The icons are drawn in the page rather than imported from an icon set.
Trademarks
Windows, PowerShell and SmartScreen are trademarks of Microsoft Corporation. Docker is a trademark of Docker, Inc. Cloudflare is a trademark of Cloudflare, Inc. Their use here is descriptive and implies no affiliation or endorsement.