Ambient CI

What it does

Build actions

The guide documents actions for Rust formatting, linting, dependency checks, documentation, builds and tests, plus Debian package builds.checked 11 Oct 2026

Build phases

CI plans can have pre-plan, plan, and post-plan actions, each running in fresh ephemeral virtual machines.checked 11 Oct 2026

Caching and artifacts

Ambient preserves cache and artifact directories between runs, with configurable maximum sizes.checked 11 Oct 2026

Dependency downloads

Vetted pre-plan actions can download dependencies before the network-isolated plan runs.checked 11 Oct 2026

Dependency support

Documented pre-plan actions download dependencies for Rust, Debian, npm, Python, and Go projects.checked 11 Oct 2026

Execution

CI plans support pre-plan, plan, and post-plan actions, each run in a fresh, ephemeral virtual machine.checked 11 Oct 2026

Git hosting

Integration with major Git hosting platforms such as GitHub and GitLab is listed as a project want, rather than a current feature.checked 11 Oct 2026

How it runs

Ambient is a command line tool for running CI locally, with jobs executed in QEMU virtual machines.checked 11 Oct 2026

How it works

Ambient processes source files into artifacts and can optionally deliver or deploy them.checked 11 Oct 2026

Installation and configuration

The user guide directs users to the source tree's INSTALL.md for installation and documents YAML project and configuration files.checked 11 Oct 2026

Isolation

The build VM has no network access, and Ambient sets resource limits for the VM.checked 11 Oct 2026

License

Ambient CI is licensed under the GNU Affero General Public License version 3 or any later version.checked 11 Oct 2026

Logs

Ambient captures build output as a run log, which may require post-processing to be useful to developers.checked 11 Oct 2026

Maintainer

The user guide is attributed to Lars Wirzenius, and the contact page identifies him as the main Ambient developer.checked 11 Oct 2026

Maturity

The project describes Ambient as alpha software that is not feature complete and may change in inconvenient ways.checked 11 Oct 2026

Network isolation

The actual build plan runs in a virtual machine with no network access; pre-plan and post-plan actions can access the network.checked 11 Oct 2026

Outputs

Post-plan actions include options to publish artifacts using rsync or dput.checked 11 Oct 2026

Publishing integrations

Post-plan actions include rsync and dput options for delivering artifacts.checked 11 Oct 2026

Purpose

Ambient CI automates builds and tests while isolating project code in a virtual machine without network access.checked 11 Oct 2026

Resource limits

Users can configure virtual machine CPU and memory, cache and artifact size limits, and the security page describes limits on disk, CPU, memory, runtime, and output.checked 11 Oct 2026

Secret handling

Configured secret files are copied only to the post-plan virtual machine and are not exposed to pre-plan or plan actions.checked 11 Oct 2026

Secrets

Configured secret files are copied only to the post-plan VM and are not exposed to pre-plan or plan actions.checked 11 Oct 2026

Support

The project recommends its issue tracker for reporting problems and also lists a fediverse contact for its main developer.checked 11 Oct 2026

Supported build actions

Documented actions include Rust checks and builds, Debian package building, shell scripts, and custom actions.checked 11 Oct 2026