The apps

Mac	macOS 26 or later, on Apple silicon
iPhone and iPad	iOS or iPadOS 26 or later, and AltStore or SideStore to install
Android	Android 15 or later, on 64-bit ARM
Android TV	Android TV or Google TV 11 or later, on 32-bit or 64-bit ARM
Windows	Windows 10 version 2004 or later, on x64 or Arm64
Linux	x86-64 or ARM64 with glibc 2.41 or newer: Ubuntu 25.04 or later (including 26.04 LTS), Fedora 42 or later, Debian 13. Not Ubuntu 24.04

The apps have mpv built in and need nothing else installed. See installation for the first start on each.

The terminal app

A prebuilt install needs only mpv and ffmpeg. The .deb pulls both in. Elsewhere, install them with brew install mpv ffmpeg, winget install shinchiro.mpv Gyan.FFmpeg, or your distro’s packages.

The Linux builds need glibc 2.28 or newer, which Debian 10, Ubuntu 20.04, RHEL 8 and every later release have. They do not run on musl distros such as Alpine.

mpv does all playback, over JSON IPC. Kaeri brings its own controls, thumbnails and shaders, so a stock mpv is enough. The player interface, with the skip button, Up Next, menus and thumbnails, needs mpv 0.36 or newer. Older versions play with mpv’s own controls; Ubuntu 24.04 ships 0.37 and Debian 12 ships 0.35.

ffmpeg remuxes downloads and handles their subtitles.

Building from source

Building also needs Rust, cmake and a C toolchain, and NASM on Windows:

macOS

brew install mpv ffmpeg cmake      # cmake builds the torrent engine's aws-lc
rustup toolchain install 1.99.1    # pinned by rust-toolchain.toml

Linux

sudo apt install mpv ffmpeg cmake build-essential pkg-config   # Debian / Ubuntu
sudo dnf install mpv ffmpeg cmake gcc-c++                      # Fedora
sudo pacman -S mpv ffmpeg cmake base-devel                     # Arch

Windows

winget install --id Rustlang.Rustup
winget install --id Kitware.CMake
winget install --id NASM.NASM
winget install --id Gyan.FFmpeg
winget install --id shinchiro.mpv
winget install --id Microsoft.VisualStudio.2022.BuildTools

NASM and the MSVC build tools are extra on Windows because the torrent stack compiles C and assembles its own crypto primitives. See installation for the full walkthrough.

cmake builds aws-lc, the crypto library under the torrent engine. Rust 1.99.1 is pinned by rust-toolchain.toml, so rustup picks it up inside the repo. To build plugins, also run rustup target add wasm32-wasip2.

Terminal emulators

Cover art looks best in a terminal with a graphics protocol, such as Ghostty, Kitty, iTerm2 or WezTerm. It renders as images over the Kitty, Sixel or iTerm2 protocols, and falls back to Unicode halfblocks elsewhere. On Windows, WezTerm is one of them.

kaeri --doctor reports what your terminal supports, which mpv you have and which config it reads, and, once torrent playback is on, where torrent traffic goes and whether the proxy check passes.