ROS2 Jazzy vs Humble: What Actually Changed for Real Robots
Andy ChenThe Short Answer
If you're starting a new robot project in July 2026, use ROS2 Jazzy, not Humble. Jazzy is the current LTS with support through May 2029, has meaningfully better Nav2 behavior-tree defaults, and is what new hardware vendors (Jetson, most LIDAR SDKs) ship drivers for first now. Stay on Humble only if you have an existing fleet you can't migrate yet.
Why This Matters
Picking a ROS2 distro isn't a one-time decision — it determines which driver packages, which Nav2 defaults, and which Gazebo version you're locked into for the multi-year life of a robot project. Migrating distros later on a robot that's already in the field is expensive, so it's worth getting right at the start rather than defaulting to whatever a five-year-old tutorial says.
Step-by-Step
1. Check hardware driver support first
Before picking a distro, check whether your LIDAR/IMU/motor controller vendor ships a Jazzy binary or only a Humble one. As of mid-2026 this gap has mostly closed, but it's still worth five minutes of checking before committing.
2. Compare what actually changed
- Nav2: Jazzy ships improved default behavior-tree recovery behaviors and better costmap performance on resource-constrained boards like the Jetson Orin Nano.
- rclpy: Jazzy's Python client library has meaningfully faster message (de)serialization for high-frequency topics (IMU, joint states).
- Gazebo: Jazzy pairs with Gazebo Harmonic by default, Humble with Gazebo Classic (now end-of-life) or Fortress.
3. Migrate incrementally if you have existing Humble code
Most user-space ROS2 node code ports with no changes — the breaking changes are almost entirely in build tooling (colcon defaults) and a handful of renamed Nav2 parameters. Budget a day for a small package, not a rewrite.
Common Errors & Fixes
| Error | Cause | Fix | Verified on |
|---|---|---|---|
| Nav2 param file fails to load after migrating from Humble | Renamed behavior-tree plugin parameters | Diff against the Jazzy Nav2 default params file, not Humble's | ROS2 Jazzy, Nav2, July 2026 |
| Gazebo Classic world files don't load | Jazzy defaults to Gazebo Harmonic, different SDF version | Convert worlds with gz sdf --convert or pin Gazebo Fortress explicitly |
ROS2 Jazzy, July 2026 |
Summary
- New projects: use Jazzy. Existing fleets: migrate when the next hardware refresh happens, not urgently.
- The real differences are in Nav2 defaults and Gazebo version, not the core ROS2 middleware.
- Check vendor driver support before committing, but as of 2026 this is rarely the blocker it was in 2024.