---
name: "kas-container"
section: "1"
platform: "linux"
package: "kas"
version: "4.8.1-2"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/kas-container"
---

# kas-container(1)

a setup tool for bitbake based projects

## NAME

kas-container - a setup tool for bitbake based projects

## DESCRIPTION

The **kas-container** script is a wrapper to run *kas* inside a build container. It gives fine grained control over the data that is mapped into the build and decouples the build environment from the host system. For details, see *Environment Variables*. The wrapper also takes care of mounting the necessary directories and setting up the environment variables inside the container.

**NOTE:**

The **kas-container** script has limited support for Git worktrees. Regular Git operations on the checked-out repository are supported. However, executing any **git worktree ...** command inside the container is not allowed.

By default **kas-container** uses the official images provided by the kas project: **ghcr.io/siemens/kas/kas\[-isar\]:\<version\>**. To specify your own image set the **KAS\_CONTAINER\_IMAGE** environment variable. The **kas-container** script version should match the kas version inside the container. If kas detects that is was called from **kas-container** and the versions do not match, a warning is emitted. This limitation might be lessened in the future, once a stable interface between **kas-container** and kas is introduced.

As container backends, Docker and Podman are supported. To force the use of podman over docker, set **KAS\_CONTAINER\_ENGINE=podman**. For details, see *Environment Variables*.

Running under docker in *rootless mode* is partially supported. It is recommended to use a distinct **KAS\_WORK\_DIR** outside of the calling directory (repo-dir), as kas temporarily changes the ownership of the working directory during its operation. All files managed by kas (including the repos) must not be written to from the host. To completely remove all data managed by kas, use **kas-container purge**. This also restores the directory owners of the dirs passed to kas, so they can be removed from the host.

**NOTE:**

The ISAR build system is not compatible with rootless execution. By that, we fall back to the system docker or podman instance.

## SEE ALSO

**[kas(1)](/kas/1.md)**,

## KAS

Part of the **[kas(1)](/kas/1.md)** suite.

## AUTHOR

Daniel Wagner, Jan Kiszka, Claudius Heine

## COPYRIGHT

Siemens and contributors, 2017-2025