Install

Download the latest release from GitHub Releases.

	Download	Needs
macOS	localhost-<version>.dmg: open it and drag localhost to Applications	macOS 15 or later, Apple silicon or Intel
Ubuntu, Debian	localhost-app_<version>_amd64.deb: sudo apt install ./localhost-app_<version>_amd64.deb	Ubuntu 22.04+, Debian 12+, x86_64
Fedora	localhost-app-<version>-1.x86_64.rpm: sudo dnf install ./localhost-app-<version>-1.x86_64.rpm	x86_64
Other Linux	localhost-app_<version>_amd64.AppImage: chmod +x it and run it	x86_64, glibc as new as Ubuntu 22.04’s
Windows	localhost_<version>_x64-setup.exe: run it. It installs for your user only, no administrator rights	Windows 10 or 11, x64; WSL 2 for Projects in WSL

Releases aren’t notarized or code-signed by a known publisher yet, so the first launch needs one extra step on macOS and Windows; see First launch. There are no Flatpak or Snap packages: their sandboxes can’t run your project’s commands.

First launch

macOS: a build that isn’t notarized

Releases aren’t notarized by Apple yet, so macOS refuses to open localhost the first time (“Apple could not verify “localhost” is free of malware…”). To open it anyway:

1. Click Done in that dialog.
2. Open System Settings → Privacy & Security and scroll to Security. It says “localhost” was blocked to protect your Mac.
3. Click Open Anyway, confirm with your password or Touch ID, then click Open Anyway once more.

macOS remembers this; each new version you download asks once again. Or, from Terminal, remove the quarantine flag the download added, only for a copy from this project’s releases:

xattr -dr com.apple.quarantine /Applications/localhost.app

Windows: SmartScreen

Unsigned releases make SmartScreen say “Windows protected your PC”. Click More info, check that the file name is what you downloaded from this project’s releases, then click Run anyway. Each new version asks once again.

Next: add your first Project.