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_posts/2026-09-08-Robotics-with-Conan-consuming-ROS.markdown

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+---
+layout: post
+comments: false
+title: "Robotics with Conan: consuming ROS as a regular package"
+description: "We have been experimenting with recipes that build ROS, the framework most robotics applications are built on, from source and expose it as a regular Conan package. These are experimental recipes, not ready for production or Conan Center. We would like to show you how it works and get your feedback about it."
+meta_title: "Robotics with Conan: consuming ROS as a regular package - Conan Blog"
+keywords: "conan, C++, ROS, ROS 2, ROS Kilted, robotics, ros-kilted, rclcpp, CMake, dependency management"
+categories: [cpp, conan, ros, ros2, robotics]
+---
+
+We know that many of you use Conan for C++ development in robotics, and that some of
+you have probably considered adding [ROS](https://docs.ros.org/) support to those projects at some point.
+**That is usually where Conan and ROS stop fitting together.** Your control, perception or planning
+code is written in C++ and managed with Conan, while ROS is a layer
+on top of it that has to be dealt with separately, installed system-wide with `apt`, `rosdep`,
+`brew` or `choco` on every developer machine and every CI agent.
+
+If you have not worked with it, ROS (Robot Operating System) is a framework for building
+robotics applications: a large set of C++ and Python libraries and tools, together with the
+conventions that let components written by different teams work with each other. Your
+components run as processes that exchange data through a publish/subscribe layer built on top
+of DDS, using standard message types for sensor data, geometry and coordinate transforms. **That
+universality is where its power comes from**: once your code speaks those interfaces, it can be
+combined with the drivers, algorithms, robot models and tools that the rest of the ecosystem
+already publishes, or with those of the partners you work with.
+
+For some months now we have been **experimenting** with [conan-io/ros-conan](https://github.com/conan-io/ros-conan),
+a set of recipes that build the [Kilted ROS distribution](https://docs.ros.org/en/kilted/Releases/Release-Kilted-Kaiju.html)
+from source and expose it as a regular Conan package for Linux, macOS and Windows. The idea we wanted to explore is whether
+**adding ROS support to a C++ project already using Conan could be one more `requires`**, instead of a separate
+installation with its own workflow. A `conan install` puts the ROS installation in your cache, and from
+there you require and consume it like any other package. It is the other direction from the
+[colcon integration we described in 2024](https://blog.conan.io/2024/11/28/Enhancing-ros-builds-with-Conan.html),
+where Conan packages are consumed transparently inside a ROS workspace: here ROS itself
+enters the usual C++ and Conan flow.
+
+> We would like to emphasize that this is **an experiment rather than a finished feature**.
+> The recipes are not finished, there are no prebuilt binaries for them and they are not
+> even included in Conan Center. This is exploratory work to propose a new approach to developing
+> robotic applications with ROS.
+
+<figure class="centered">
+    <video controls playsinline preload="metadata" width="100%"
+           poster="{{ site.baseurl }}/assets/post_images/2026-09-08/pose-estimation-ros-kilted-rviz2.jpg">
+        <source src="{{ site.baseurl }}/assets/post_images/2026-09-08/ros-conan-screencast.mp4" type="video/mp4">
+        <a href="{{ site.baseurl }}/assets/post_images/2026-09-08/ros-conan-screencast.mp4">Download the video</a>
+    </video>
+    <figcaption style="text-align: center; font-size: 0.9em;">
+        The <a href="https://github.com/conan-io/ros-conan/tree/main/examples/pose_estimation">pose_estimation</a>
+        example: a ROS node that tracks human pose from an image input, with
+        <code>ros-kilted</code>, <code>opencv</code> and <code>tensorflow-lite</code>
+        resolved in a single dependency graph
+    </figcaption>
+</figure>
+
+## What consuming it looks like
+
+By exploring the folder of the example shown above:
+
+```bash
+cd ros-conan/examples/pose_estimation
+tree
+.
+├── assets
+│   ├── dancing.mp4
+│   ├── dancing.png
+│   ├── lite-model_movenet_singlepose_lightning_tflite_float16_4.tflite
+│   └── output.gif
+├── ci_test_example.py
+├── CMakeLists.txt
+├── conanfile.txt
+├── readme.md
+└── src
+    └── pose-estimation.cpp
+```
+
+You can check that ROS shows up as one more `requires`:
+
+**`conanfile.txt`**
+
+```ini
+[requires]
+ros-kilted/2026.06.17
+tensorflow-lite/2.15.0
+opencv/4.12.0
+
+[generators]
+CMakeToolchain
+CMakeDeps
+
+[layout]
+cmake_layout
+```
+
+On the CMake side, ROS packages are located with their usual
+`find_package()` calls. The recipe puts the ROS installation on
+`CMAKE_PREFIX_PATH`, so the config files that ROS itself installs are the
+ones being used:
+
+**`CMakeLists.txt`**
+
+```cmake
+find_package(rclcpp REQUIRED)
+find_package(geometry_msgs REQUIRED)
+find_package(visualization_msgs REQUIRED)
+find_package(tensorflowlite REQUIRED)
+find_package(OpenCV REQUIRED)
+
+add_executable(pose-estimation src/pose-estimation.cpp)
+target_link_libraries(pose-estimation PRIVATE rclcpp::rclcpp
+                                              ${geometry_msgs_TARGETS}
+                                              ${visualization_msgs_TARGETS}
+                                              tensorflow::tensorflowlite
+                                              opencv::opencv)
+```
+
+**`ros-kilted` is more than the C++ client library.** The recipe packages the distribution, so besides
+`rclcpp` you get the standard message packages such as `geometry_msgs` or `sensor_msgs` and,
+depending on the variant you pick, coordinate transforms with `tf2` or the visualization tools.
+The `variant` recipe option ranges from `core` (default) to `desktop` and decides how much of ROS gets built.
+
+The recipes are not in Conan Center, so `ros-kilted` is resolved by cloning the repository next
+to your project and adding it as a
+[local-recipes-index](https://docs.conan.io/2/devops/devops_local_recipes_index.html) remote. That
+clone is also where the `profiles/ros` profile comes from. The two commands for that are in the
+[README](https://github.com/conan-io/ros-conan#quick-start):
+
+```bash
+git clone https://github.com/conan-io/ros-conan.git
+conan remote add ros-conan ./ros-conan --type=local-recipes-index
+```
+
+Then the usual install and build sequence of any Conan project:
+
+```bash
+conan install --profile=ros-conan/profiles/ros --build=missing
+cmake --preset conan-release
+cmake --build --preset conan-release
+```
+
+> **Note**: on Windows, building ROS produces deep directory trees that exceed the default
+> 260-character path limit. Enable
+> [long paths](https://learn.microsoft.com/en-us/windows/win32/fileio/maximum-file-path-limitation?tabs=registry#enable-long-paths-in-windows-10-version-1607-and-later)
+> before running `conan install`.
+
+One good thing about this approach is that there is no need to bring all the usual ROS
+tooling and workspace conventions into your C++ project. **The application stays a plain
+CMake project that happens to require ROS.** For a codebase where ROS is one layer of a
+larger C++ product, we think that is a reasonable place to be, but we would like to hear
+whether it holds up in a real project.
+
+## What this brings
+
+These are the advantages we see in the approach, and the reason we consider this work worth
+sharing:
+
+- **One dependency graph.** ROS is resolved together with the rest of your requirements, so
+  Conan can detect version conflicts between the robotics libraries and everything else.
+- **No system-wide install.** ROS lives in the Conan cache, so different versions can coexist on
+  the same machine and each project activates the one it needs.
+- **The same tooling as the rest of your dependencies.** Profiles, options, lockfiles, remotes
+  and CI pipelines apply to ROS as they do to any other package, with the same commands on the
+  three platforms.
+- **Composable with Conan Center.** Robotics applications often need
+  [opencv](https://conan.io/center/recipes/opencv), [eigen](https://conan.io/center/recipes/eigen)
+  or [tensorflow-lite](https://conan.io/center/recipes/tensorflow-lite) among others, and those come from the
+  same graph, with no glue in between.
+
+## The ROS tools still work as usual
+
+If you are already familiar with ROS, the `ros-kilted` recipe brings a couple of conveniences:
+the whole installation arrives with a single `conan install`, and the `ros2` commands can be run
+without sourcing anything by hand. Everything else behaves as the
+[official tutorials](https://docs.ros.org/en/kilted/Tutorials.html) describe. Here is `turtlesim`,
+the small simulator used to introduce ROS, launched straight from the installation Conan provides.
+It is part of the `desktop` variant, so that is the one to select.
+
+Using a **`conanfile.txt`**, you can declare the `desktop` variant:
+
+```ini
+[requires]
+ros-kilted/2026.06.17
+
+[options]
+ros-kilted/*:variant=desktop
+```
+
+And then execute `ros2` directly from the `conan run`:
+
+```bash
+conan run "ros2 run turtlesim turtlesim_node" --profile=ros-conan/profiles/ros --build=missing
+```
+
+<figure class="centered">
+    <img src="{{ site.baseurl }}/assets/post_images/2026-09-08/ros-kilted-turtlesim.jpg"
+         style="display: block; margin-left: auto; margin-right: auto;"
+         alt="turtlesim window launched from a Conan-provided ROS installation"/>
+    <figcaption style="text-align: center; font-size: 0.9em;">
+        turtlesim launched from a Conan-provided ROS installation
+    </figcaption>
+</figure>
+
+## We would like to know what you think
+
+Now that we have introduced this way of installing ROS with Conan, we would like to know if this approach makes sense to you.
+We encourage you to try the examples in the [conan-io/ros-conan](https://github.com/conan-io/ros-conan) repository (if you have not already) and tell us what you think by [opening an issue on GitHub](https://github.com/conan-io/ros-conan/issues).
+Any feedback is greatly appreciated!
+
+**We will also be at ROSCon Global 2026 in Toronto**. If you are attending, we would
+be happy to talk about this in person.
+
+Hope to see you there!