Fresco vs Hydra

Fresco is a Linux desktop app for setting video, GIF, slideshow, image, and playlist wallpapers as animated backgrounds. Slideshows can use transitions, and the app includes a catalog of curated, licensed wallpapers. Each monitor can have its own wallpaper, selected from a wallpaper’s context menu. Four widgets are available: synced lyrics, a clock, an audio visualiser, and album art on a turning record. Lyrics follow media over MPRIS, checking local .lrc files before LRCLIB. Video playback uses GPU hardware decoding through mpv with VA-API or NVDEC. Fresco supports X11 and the Wayland layer-shell compositors COSMIC, Hyprland, Sway, and KDE Plasma 6. On GNOME Wayland it displays a still frame, and widgets are unavailable because there is no live wallpaper surface. It can pause on battery or when a window goes fullscreen on a display. A daemon keeps wallpapers running after the app closes and restores them after reboot. Fresco is free forever, licensed under GPL-3.0, and made by Dibbayajyoti Roy. Distribution options include a one-line installer, a .deb release, and the deepin App Store.

Hydra is a continuous integration service for projects based on Nix. It checks out project source periodically or continuously, builds it, runs tests, and produces reports. Work is organized into jobsets whose inputs can trigger builds when they change; jobsets can also depend on one another. Flake jobsets are supported when their outputs expose a hydraJobs attribute set. Jobs can produce packages, ISO images, or tarballs, and jobset inputs can use Git checkout sources. Hydra also provides a JSON API. It is aimed at Nix and NixOS package developers, not people who only need to use NixOS. Hydra is open source under GPL-3.0 and listed at free. It is self-hosted, with no hosted option listed, and running it is currently supported only on NixOS; the repository recommends the NixOS module for production. Flake evaluation is restricted from accessing files outside the Nix store. Some state is stored in the database, so backups are needed, and the wiki reports that hydra-queue-runner can sometimes leave queued builds unscheduled.