Herdr GPUI

Releases · App updates · GUI scope & configuration · Performance report · Contributing

A native Rust/GPUI client for a Herdr daemon you installed yourself. It paints the daemon's terminal cells, split panes included, without running another terminal emulator or wrapping the TUI.

Unaffiliated project. Not affiliated with, endorsed by, or supported by Herdr or herdr.dev.

Install

macOS with Homebrew

Requires Homebrew and macOS 15 Sequoia or newer, on Apple Silicon or Intel. The cask installs the signed, notarized universal app.

brew install penso/tap/herdr-gpui
open -a Herdr

brew install resolves casks directly, so --cask is not required. To update it later, or to install by its short name, tap once first:

brew tap penso/tap
brew install herdr-gpui

The cask is published from the tap by the release workflow. A cask install updates itself through Homebrew: the in-app updater detects that Homebrew owns the bundle and runs brew upgrade --cask herdr-gpui for you, so Homebrew's records stay correct. If its metadata is stale, the updater runs brew update and retries once. The update panel shows progress throughout. macOS .dmg, experimental Linux packages, and experimental Windows .zips are also published on Releases.

Linux packages

Each release publishes x86_64 and ARM64 builds as a .deb, an .rpm, an Arch Linux package, and a plain tarball, all containing the same executable. They need glibc 2.39 or newer (Ubuntu 24.04, Debian 13, Fedora 40, current Arch, or later). Download the file for your architecture from Releases, then:

sudo apt install ./Herdr-VERSION-x86_64-unknown-linux-gnu.deb      # Debian, Ubuntu
sudo dnf install ./Herdr-VERSION-x86_64-unknown-linux-gnu.rpm      # Fedora
sudo pacman -U Herdr-VERSION-x86_64-unknown-linux-gnu.pkg.tar.zst  # Arch Linux

The package manager pulls in the runtime libraries, including the Vulkan loader; a Vulkan driver for your GPU must also be present. Packages are not in any distribution repository, so they never update themselves: install each new release the same way. Before a release, CI installs each package on Ubuntu 24.04, Debian 13 and Fedora 42, and the x86_64 Arch package on Arch Linux, then checks that the executable finds every library. The ARM64 Arch package targets Arch Linux ARM and is not install-tested.

On NixOS, or anywhere with Nix, build from source with the repository's flake:

nix run github:penso/herdr-gpui
# or add it to a configuration: inputs.herdr-gpui.url = "github:penso/herdr-gpui";
# then environment.systemPackages = [ inputs.herdr-gpui.packages.${system}.default ];

The flake builds with the toolchain pinned in rust-toolchain.toml on x86_64 and ARM64 Linux. Like the packages, it never updates itself.

From source

Install Rust/rustup and, on macOS, the Xcode command-line tools. The repository pins Rust 1.96.1 and GPUI 0.3.6 (the gpui-pre snapshot crate); the Rust version is declared in rust-toolchain.toml and mirrored in mise.toml, so mise install also provisions it.

git clone https://github.com/penso/herdr-gpui.git
cd herdr-gpui
just run

just run uses the optimized release build with the QA menu enabled; just run-debug is notably slower with a dense terminal on screen. Without just: cargo run --locked --release -p herdr-gpui --features qa-menu.

Install the Herdr daemon separately. The app starts an already-installed local herdr server when the target session is absent, but never installs or upgrades a daemon. Explicitly confirming session deletion stops that named session first; closing or removing the GUI leaves daemon sessions and shared Herdr configuration intact.

Linux Builds

On Ubuntu 24.04 (x86_64 or ARM64), run bash scripts/install-linux-deps.sh before building. This installs GPUI's X11/Wayland/font development dependencies and libasound2-dev for Rodio/CPAL native audio. CI and release builds use the same script. Linux binaries require the system ALSA shared library (libasound2t64 on Ubuntu 24.04), a configured default audio device, and Vulkan for rendering. Audio normally routes through the desktop's ALSA plugin configuration; no CLI audio player is required. Custom notification sounds are MP3 only. See notification sounds.

Windows

Windows is experimental, not a supported platform: CI checks formatting, lints every target and feature, and runs workspace tests with default and all features on windows-2025, including headless UI and CLI tests. The release workflow also builds and CLI-tests the optimized executable, but no native window, renderer, or live daemon has been exercised. Local connections use the named pipe the Windows daemon binds, and configuration and state follow its %APPDATA% / %LOCALAPPDATA% layout. Saved SSH hosts, in-app updates, saved GitHub credentials, and the avatar disk cache are unavailable and report that plainly; see the GUI README.

Each release publishes Herdr-VERSION-x86_64-pc-windows-msvc.zip and Herdr-VERSION-aarch64-pc-windows-msvc.zip (native ARM64), each containing herdr-gpui.exe and its license notices. They carry the same checksums, Sigstore signatures, and build provenance as the other assets, but they are not Authenticode-signed, so SmartScreen warns on first launch, and they never update themselves: download each new release manually. The executable is console-subsystem, so launching it from Explorer also opens a console window.

How it connects

flowchart LR
    subgraph app["Herdr GPUI (this repo)"]
        ui["herdr-gpui<br/>window, painting, input"]
        client["herdr-client<br/>discovery, socket worker, sessions"]
        proto["herdr-protocol<br/>framing, surface patches"]
        ui --> client --> proto
    end

    proto <-->|"bincode frames over<br/>herdr-client.sock"| daemon

    subgraph host["Your machine or a saved SSH host"]
        daemon["herdr daemon"]
        daemon --> terms["terminal processes,<br/>workspaces, agents"]
    end

Loading

The daemon owns the terminals and all session state. The GUI attaches to the binary client socket, renders the surfaces it is sent, and sends semantic input back. Closing or detaching the GUI leaves the daemon and its terminals running.

Browser tabs are the exception: Herdr has no browser panes, so web pages shown beside a workspace's terminals belong to the GUI alone. Agents in your panes open them with herdr-gpui browser open URL, which reaches the running app over a local socket of its own.

Audio Test

The QA menu is excluded from default Cargo builds, including published releases. just run enables it automatically; with Cargo, use cargo run --locked --release -p herdr-gpui --features qa-menu. To manually test native audio in that build, choose QA > Play Sound. It plays the built-in Done sound on the background Rodio worker, even without a daemon or active pane and even with notifications muted. HERDR_DISABLE_SOUND and NEXTEST still suppress playback. See notification sounds for queue limits and playback details.

Performance

just test-perf opens a daemon-free native fixture with a dense 160x50 terminal, 40 workspaces, and 40 agents. It dispatches real window-local mouse/scroll events and measures cold frames, warm hover, and both sidebar lists' scrolling. It also asserts that unchanged terminal cells need zero new text-shaping calls, validates batched background counts, and compares cached glyphs with freshly shaped ones.

On the development M4 Max, caching and background batching reduced release hover p95 from about 51 ms to 12 ms, and scrolling from 56 ms to 14 ms. The benchmark measures CPU event-to-scene construction, not GPU completion or pointer-to-screen latency. Use just test-perf 50 to set a different calibrated budget; native tests remain opt-in rather than imposing machine-dependent timings on hosted CI.

See PERFORMANCE.md for the before/after results, reference mode, workload, deterministic checks, and remaining limitations.

License

Apache-2.0. See LICENSE and NOTICE, plus the upstream protocol attribution for the vendored parts of herdr-protocol.