Install ROS 2 Lyrical Luth on Ubuntu from Debian packages and verify with the talker/listener demo

Documented steps

1. Check the platform first: ROS 2 Lyrical Luth (released May 2026, LTS supported until May 2031) targets Ubuntu Resolute 26.04 as Tier 1 on amd64/arm64 with Debian packages. Ubuntu Noble 24.04 is only Tier 3 for Lyrical and must be built from source. RHEL 10 is Tier 2; Windows 11 (VS2022) is Tier 1 by archive.
2. Set a UTF-8 locale: `locale`; `sudo apt update && sudo apt install locales`; `sudo locale-gen en_US en_US.UTF-8`; `sudo update-locale LC_ALL=en_US.UTF-8 LANG=en_US.UTF-8`; `export LANG=en_US.UTF-8`.
3. Enable the Universe repository: `sudo apt install software-properties-common` then `sudo add-apt-repository universe`.
4. Install curl, then bootstrap the ROS apt repo with the ros2-apt-source package (this replaces the older manual key + sources.list.d procedure): `sudo apt update && sudo apt install curl -y`; `export ROS_APT_SOURCE_VERSION=$(curl -s https://api.github.com/repos/ros-infrastructure/ros-apt-source/releases/latest | grep -F "tag_name" | awk -F'"' '{print $4}')`.
5. Download and install it: `curl -L -o /tmp/ros2-apt-source.deb "https://github.com/ros-infrastructure/ros-apt-source/releases/download/${ROS_APT_SOURCE_VERSION}/ros2-apt-source_${ROS_APT_SOURCE_VERSION}.$(. /etc/os-release && echo ${UBUNTU_CODENAME:-${VERSION_CODENAME}})_all.deb"` then `sudo dpkg -i /tmp/ros2-apt-source.deb`.
6. Optional development tooling: `sudo apt update && sudo apt install ros-dev-tools`.
7. Refresh and upgrade: `sudo apt update && sudo apt upgrade`.
8. Install ROS 2: desktop (RViz, demos, tutorials) `sudo apt install ros-lyrical-desktop`, or headless `sudo apt install ros-lyrical-ros-base`.
9. Source the environment in every new terminal: `source /opt/ros/lyrical/setup.bash` (setup.sh / setup.zsh for other shells).
10. Verify: terminal 1 `source /opt/ros/lyrical/setup.bash && ros2 run demo_nodes_cpp talker`; terminal 2 `source /opt/ros/lyrical/setup.bash && ros2 run demo_nodes_py listener`. The listener should echo the talker's messages.
11. To uninstall: `sudo apt remove '~nros-lyrical-*' && sudo apt autoremove`, and optionally `sudo apt remove ros2-apt-source`.
12. Official doc: https://docs.ros.org/en/lyrical/Installation/Ubuntu-Install-Debs.html