add-apt-repository

Add a new apt repository

$ add-apt-repository [repository_spec]

$ add-apt-repository [[-r|--remove]] [repository_spec]

$ add-apt-repository --update [repository_spec]

$ add-apt-repository [[-s|--enable-source]] [repository_spec]

add-apt-repository [options] repository

-r, --remove
    Remove the specified repository

-y, --yes
    Assume yes to all queries automatically

-n, --no-update
    Do not run apt update after adding

--update
    Run apt update after adding (default)

-k KEYID
    Use specific key ID instead of auto-downloading

--list
    List all configured repositories

-m, --mass
    Mass mode for scripting multiple operations

The add-apt-repository command is a convenience script primarily used on Debian-based systems like Ubuntu to easily add Personal Package Archives (PPAs) or other third-party repositories to the APT package manager's sources. It simplifies the process by automatically handling the addition of repository entries to /etc/apt/sources.list.d/, importing required GPG keys for repository verification, and optionally updating the package cache.

When adding a PPA, specify it in the format ppa:user/ppa-name, and the command resolves it to the full deb line, fetches the signing key from Launchpad, and configures everything. For custom repositories, provide the full sources.list line. This eliminates manual editing of sources files and key management, reducing errors.

It's part of the software-properties-common package, essential for modern Ubuntu workflows. Users rely on it for accessing software not in official repos, like newer versions of apps or drivers. However, adding untrusted repos can pose security risks, so verify sources first.

After adding, run apt update to refresh indices (enabled by default unless disabled). Removal reverses the process cleanly.

Requires software-properties-common package; risky with untrusted repos as it adds keys to system trust; PPAs are Ubuntu-specific and may break on non-Ubuntu Debian; always review output before confirming.

add-apt-repository ppa:deadsnakes/ppa
Adds Python versions PPA.

add-apt-repository -r ppa:deadsnakes/ppa
Removes it.

add-apt-repository 'deb http://archive.ubuntu.com/ubuntu focal main'
Adds custom sources line.

Use ppa:namespace/ppa-name for Launchpad PPAs; command expands to full deb http://ppa.launchpad.net/... lines and imports keys.

Introduced in Ubuntu 9.10 (Karmic) as part of python-software-properties package to streamline PPA usage amid growing Launchpad adoption; evolved into software-properties-common by Ubuntu 16.04; widely used in Ubuntu derivatives but absent in pure Debian.

apt(8), apt-get(8), apt-key(8), software-properties(7)