Offline and Air-Gapped Installs#

cx supports two offline deployment styles:

  • cxz: one binary with the locked package archives embedded.

  • cx plus a bundle directory: one small binary and a separate directory of .conda or .tar.bz2 archives.

Use cxz when you want the transfer artifact to be a single file. Use a bundle directory when an installer system, container build, or enterprise software distribution process already manages package files separately.

conda-express publishes the online cx runtime and the embedded cxz runtime. It does not currently publish conda-ship external layout release assets such as cx.bundle.tar.zst. The CX_BUNDLE control below is for deployment systems that provide a bundle directory next to cx. For custom external-bundle artifacts, use conda-ship’s external artifact layout.

Use cxz#

Download the cxz file for the target platform from the release page, make it executable on Unix, then run a conda command with offline mode enabled:

chmod +x cxz-x86_64-unknown-linux-gnu
CX_PREFIX=/opt/cx CX_OFFLINE=1 ./cxz-x86_64-unknown-linux-gnu info

The first command bootstraps the prefix from the embedded bundle, then runs conda info. The embedded bundle is detected automatically, so you do not need CX_BUNDLE. CX_OFFLINE=1 makes the runtime refuse network access if anything is missing.

Use a Bundle Directory#

When package archives are stored separately by your installer, image build, or software distribution process, point cx at the bundle directory and use offline mode:

CX_PREFIX=/opt/cx \
CX_BUNDLE=/path/to/packages \
CX_OFFLINE=1 \
cx info

The same settings are available as environment variables for installer scripts and CI jobs:

CX_PREFIX=/opt/cx CX_BUNDLE=/path/to/packages CX_OFFLINE=1 cx info

Use the installer script#

The shell and PowerShell installers pass CX_BUNDLE and CX_OFFLINE to the first conda command that triggers automatic bootstrap:

curl -fsSL https://jezdez.github.io/conda-express/get-cx.sh \
  | env CX_BUNDLE=/path/to/packages CX_OFFLINE=1 sh

On Windows:

$Env:CX_BUNDLE = "C:\packages"
$Env:CX_OFFLINE = "1"
irm https://jezdez.github.io/conda-express/get-cx.ps1 | iex

Verify artifacts before use#

Each GitHub Release artifact has a matching checksum and GitHub Artifact Attestation. For example:

gh attestation verify ./cx-x86_64-unknown-linux-gnu \
  -R jezdez/conda-express \
  --signer-workflow jezdez/conda-express/.github/workflows/release.yml

For disconnected environments, perform verification before transferring the binary or bundle directory across the boundary. See Verify Release Artifacts for the full checklist.