Ambient CI

Spec sheet

What it does

Ambient CI builds software and runs automated tests while isolating project code in a virtual machine.Read 11 Oct 2026 · doc.liw.fi

Purpose

Ambient CI automates builds and tests while isolating project code in a virtual machine without network access.Read 11 Oct 2026 · ambient.liw.fi

Support

The project recommends its issue tracker for reporting problems and also lists a fediverse contact for its main developer.Read 11 Oct 2026 · ambient.liw.fi

License

Ambient CI is licensed under the GNU Affero General Public License version 3 or any later version.Read 11 Oct 2026 · ambient.liw.fi

Build actions

The guide documents actions for Rust formatting, linting, dependency checks, documentation, builds and tests, plus Debian package builds.Read 11 Oct 2026 · doc.liw.fi

Build phases

CI plans can have pre-plan, plan, and post-plan actions, each running in fresh ephemeral virtual machines.Read 11 Oct 2026 · doc.liw.fi

Caching and artifacts

Ambient preserves cache and artifact directories between runs, with configurable maximum sizes.Read 11 Oct 2026 · doc.liw.fi

Dependency downloads

Vetted pre-plan actions can download dependencies before the network-isolated plan runs.Read 11 Oct 2026 · doc.liw.fi

Dependency support

Documented pre-plan actions download dependencies for Rust, Debian, npm, Python, and Go projects.Read 11 Oct 2026 · doc.liw.fi

Execution

CI plans support pre-plan, plan, and post-plan actions, each run in a fresh, ephemeral virtual machine.Read 11 Oct 2026 · doc.liw.fi

Git hosting

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

How it runs

Ambient is a command line tool for running CI locally, with jobs executed in QEMU virtual machines.Read 11 Oct 2026 · ambient.liw.fi

How it works

Ambient processes source files into artifacts and can optionally deliver or deploy them.Read 11 Oct 2026 · ambient.liw.fi

Installation and configuration

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

Isolation

The build VM has no network access, and Ambient sets resource limits for the VM.Read 11 Oct 2026 · ambient.liw.fi

Logs

Ambient captures build output as a run log, which may require post-processing to be useful to developers.Read 11 Oct 2026 · ambient.liw.fi

Maintainer

The user guide is attributed to Lars Wirzenius, and the contact page identifies him as the main Ambient developer.Read 11 Oct 2026 · ambient.liw.fi

Maturity

The project describes Ambient as alpha software that is not feature complete and may change in inconvenient ways.Read 11 Oct 2026 · ambient.liw.fi

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.Read 11 Oct 2026 · doc.liw.fi

Outputs

Post-plan actions include options to publish artifacts using rsync or dput.Read 11 Oct 2026 · doc.liw.fi

Publishing integrations

Post-plan actions include rsync and dput options for delivering artifacts.Read 11 Oct 2026 · doc.liw.fi

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.Read 11 Oct 2026 · ambient.liw.fi

Secret handling

Configured secret files are copied only to the post-plan virtual machine and are not exposed to pre-plan or plan actions.Read 11 Oct 2026 · doc.liw.fi

Secrets

Configured secret files are copied only to the post-plan VM and are not exposed to pre-plan or plan actions.Read 11 Oct 2026 · doc.liw.fi

Supported build actions

Documented actions include Rust checks and builds, Debian package building, shell scripts, and custom actions.Read 11 Oct 2026 · doc.liw.fi

Where Specifiction places it

• Continuous Integration Software#31 of 587.8