Kometka adds Letterboxd, IMDb and Rotten Tomatoes ratings to Jellyfin posters
A Jellyfin user has published Kometka, a small personal project that overlays Letterboxd, IMDb and Rotten Tomatoes ratings directly onto movie posters in a Jellyfin library. The author shared it on r/jellyfin on November 7, 2026, and describes it as a tiny, Kometa-inspired app rather than a plugin.
The mechanics are straightforward. Kometka pulls rating data from MDBList, applies the values to the poster images, and refreshes them on a schedule you configure. Original posters are backed up before anything is changed. Because the overlays are written into the images themselves rather than added by a client-side layer, they appear in any Jellyfin client without extra setup. It ships as a Docker image and is configured mainly through a small number of environment variables.
It is worth being clear about the scale here: the author says the tool is currently used by three people, including themselves. TV show support is planned, along with quality-of-life work such as letting users pick whether Letterboxd ratings keep their native 5-point scale or get converted to 10 points. The author also notes, openly, that AI was used in a limited capacity during development, as documented in the repository's authorship disclaimer.
Who this affects: anyone running Jellyfin who likes the look of rating badges on posters but does not want to run a full metadata pipeline to get them. It is also relevant to people who already use Kometa-style overlays and want something lighter.
Why it matters: poster overlays are one of those small cosmetic touches that make a library feel finished, and doing them at the image level is the pragmatic choice when you want consistent results across clients. The backup step is the detail that matters most — it means a bad run is recoverable.
Commentary for self-hosters
Treat this as an early-stage tool and plan accordingly. Three users is not a track record, so test it on a copy of your poster directory or a small library section before pointing it at everything, and keep your own backups on top of the ones the app makes. Environment-variable configuration keeps the container simple, but it also means reading the repository carefully before you deploy.
If you already run a metadata manager, check whether it can do the same job before adding another container to maintain. If you want a lighter path, a single Docker service that touches only images is easy to reason about and easy to remove. Either way, pin the image tag rather than tracking latest, and check the changelog before updating once TV support lands.
If you would rather extend Jellyfin through supported plugins, have a look at our Jellyfin plugins.
Source: Adding Kometa-style ratings to Jellyfin