When I say "universal", I mean it downloads binaries from GitHub releases.

When I say "binary", I mean it handles single-file executables like those created by most Go and Rust projects.

When I say "installer", I mean it plops the binary wherever you tell it to.

And finally, when I say "UBI", I don't mean "universal basic income", but that'd be nice too.

You can install it by hand by downloading the latest release from the releases page.

There are also bootstrap install scripts that provide a half-assed implementation of ubi:

curl --silent --location \
    https://raw.githubusercontent.com/houseabsolute/ubi/master/bootstrap/bootstrap-ubi.sh |
    sh

If you run this as a non-root user, it will install ubi into $HOME/bin. If run as root it installs it into /usr/local/bin.

To install ubi into an arbitrary location, set the $TARGET env var:

curl --silent --location \
    https://raw.githubusercontent.com/houseabsolute/ubi/master/bootstrap/bootstrap-ubi.sh |
    TARGET=~/local/bin sh

If the GITHUB_TOKEN env var is set, then the bootstrap script will use this when it hits the GitHub API. This is only necessary if you are hitting the GitHub anonymous API usage limits. This is unlikely to happen unless you're running the bootstrap script repeatedly for testing.

To install a specific version of ubi, set the TAG env var:

curl --silent --location \
    https://raw.githubusercontent.com/houseabsolute/ubi/master/bootstrap/bootstrap-ubi.sh |
    TAG=~v0.0.15 sh

powershell -exec bypass -c "Invoke-WebRequest -URI 'https://raw.githubusercontent.com/houseabsolute/ubi/master/bootstrap/bootstrap-ubi.ps1' -UseBasicParsing | Invoke-Expression"

You can run this from a command or Powershell command line. This will install ubi.exe into the directory where you run this.

USAGE:
    ubi [OPTIONS]

OPTIONS:
    -d, --debug                  Enable debugging output
    -e, --exe <exe>              The name of this project's executable. By default this is the same
                                 as the project name, so for houseabsolute/precious we look for
                                 precious or precious.exe. When running on Windows the ".exe" suffix
                                 will be added as needed.
    -h, --help                   Print help information
    -i, --in <in>                The directory in which the binary should be placed. Defaults to
                                 ./bin.
    -m, --matching <matching>    A string that will be matched against the release filename when
                                 there are multiple files for your OS/arch, i.e. "gnu" or "musl".
                                 Note that this will be ignored if there is only used when there is
                                 only one matching release filename for your OS/arch
    -p, --project <project>      The project you want to install, like houseabsolute/precious or
                                 https://github.com/houseabsolute/precious.
    -q, --quiet                  Suppresses most output
        --self-upgrade           Use ubi to upgrade to the latest version of ubi. The --exe, --in,
                                 --project, --tag, and --url args will be ignored.
    -t, --tag <tag>              The tag to download. Defaults to the latest release.
    -u, --url <url>              The url of the file to download. This can be provided instead of a
                                 project or tag. This will not use the GitHub API, so you will never
                                 hit the GitHub API limits. This means you do not need to set a
                                 GITHUB_TOKEN env var except for private repos.
    -v, --verbose                Enable verbose output
    -V, --version                Print version information

If the GITHUB_TOKEN environment variable is set, then this will be used for all API calls. This is required to download releases for a private project. If you are running ubi in a CI environment that runs jobs frequently, you may also need this, as GitHub has a very low rate limit for anonymous API requests.

However, you can also use the --url option to bypass the GitHub API by providing the download link directly.

You can run ubi --self-upgrade to upgrade ubi using ubi. Note that you must have write permissions to the directory containing ubi for this to work.

This does not work on Windows. See GH #21.

There are a few things you'll want to consider when using ubi in CI.

First, there are the GitHub API rate limits. These can be as low as 60 requests per hour per IP when not providing a GITHUB_TOKEN, so you will almost certainly want to provide this. When running in GitHub Actions you can use the ${{ secrets.GITHUB_TOKEN }} syntax to set this env var, and in that case the rate limits are per repository.

- name: Install UBI
  shell: bash
  run: |
    curl --silent --location \
        https://raw.githubusercontent.com/houseabsolute/ubi/master/bootstrap/bootstrap-ubi.sh |
        sh
  env:
    GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

If you only run ubi on one platform, you can avoid hitting the GitHub API entirely by using the --url parameter. But if you run on multiple platforms this can be tedious to maintain and it largely defeats the purpose of using ubi.

If you are downloading executables from repos you don't control and you don't use the --url parameter, then you should use the --tag parameter to specify the release version you want to install. Otherwise ubi will always download the latest version, which can lead to surprise breakage in CI.

With the rise of Go and Rust, it has become increasingly common for very useful tools like ripgrep to publish releases in the form of a tarball or zip file containing a single executable. Having a single tool capable of downloading the right binary for your platform is quite handy.

Yes, this can be done in half a dozen lines of shell on Unix systems, but do you know how to do the equivalent in Powershell?

Once you have ubi installed, you can use it to install any of these single-binary tools available on GitHub, on Linux, macOS, and Windows.

I think so. While you can of course use go or cargo to install these tools, that requires an entire language toolchain. Then you have to actually compile the tool, which may require downloading and compiling many dependencies. This is going to be a lot slower and more error prone than installing a binary.

That's debatable. The big advantage of using ubi is that you can use the exact same tool on Linux, macOS, and Windows. The big disadvantage is that you don't get a full package that contains metadata (like a license file) or extras like shell completion files, nor can you easily uninstall it using a package manager.