e5 (ensure)

Crude package installation manager. Define your tools in requirements.toml,
run e5 sync.

Overview

What e5 isn't:

A package/dependency manager
A build tool

What it is:

A simple utility for installing necessary tools in development and CI
environments. It's supposed to streamline bare GitHub actions provisioning, and
make it easier for new developers to get started with building their projects.

Usage

e5 sync                  # Install all packages from requirements.toml
e5 list                  # Show status of required packages
e5 list --available      # List all packages in repository
e5 search <query>        # Search for packages
e5 show <package>        # Show package details

Custom Repository

By default, e5 fetches recipes from this repository. You can use a custom
repository via --repo-url flag or E5_REPO_URL environment variable:

# Remote repository
e5 --repo-url "https://example.com/my-repo" sync

# Local folder (file:// schema)
e5 --repo-url "file:///path/to/local/repo" sync

# Via environment variable
E5_REPO_URL="file:///home/user/my-repo" e5 sync

A repository must contain an index.toml and recipe files. See the repo/
folder for the expected structure.

requirements.toml

packages = [
  "hurl",
  "taplo@0.9.3",      # pin specific version
  "protobuf-compiler",
]

Version Pinning

You can pin packages to specific versions using the package@version syntax.
However, version pinning support varies by backend:

Backend	Version Support	Notes
apt	Yes	Uses `apt-get install package=version` syntax
script	Yes	Version passed as `VERSION` environment variable
homebrew	No	Use versioned formula names instead (e.g., `node@18`)
pacman	No	Use script backend with Arch Linux Archive for specific versions

When a version is specified but the backend doesn't support it, a warning is
displayed and the latest version is installed.

Installation Fallback

e5 automatically tries multiple installation methods if one fails. The fallback
order is:

Native package manager (apt, pacman) - highest priority
Homebrew - cross-platform fallback
Script - universal fallback

For example, if a package has both apt and script installation methods
defined and apt fails (e.g., version not available), e5 will automatically try
the script method.

Use e5 show <package> to see the fallback chain for a specific package.

Security

e5 is designed to be as crude as possible. It will eval some commands on your
system, which can lead to eg.: secret exfiltration. It's also designed to be ran
in a privileged environment. One may guess what kind of attacks this may lead
to.

If you are using it, create your own package repository to ensure you control
the scripts that are executed.

luke-biel/e5