Conda License Lint: Anaconda defaults channel
Six paid Anaconda channel lines in one environment.yml, found and fixed in the editor. For Python and data teams at organisations with 200 or more people, every defaults, anaconda, repo.anaconda.com or pkgs/main:: line in a conda file pulls packages from Anaconda's licensed repository.
Full rule reference: https://getreadystack.com/tools/conda-channel-license-lint
Yardstick: Anaconda Business is listed at $50 per user per month; conda-forge is free for everyone.
What it checks (8 rules)
| Rule |
Severity |
What it catches |
defaults-channel |
error |
- defaults in channels: — short-hand for repo.anaconda.com/pkgs/main and pkgs/r (plus pkgs/msys2 on Windows) |
anaconda-channel |
error |
- anaconda — the anaconda.org mirror of defaults, under the same terms |
repo-anaconda-url |
error |
any https://repo.anaconda.com/... channel URL |
pkgs-channel-name |
error |
pkgs/main, pkgs/r, pkgs/msys2 short names |
channel-pinned-dependency |
error |
defaults::pandas, pkgs/main::numpy=1.26 — a pin that bypasses a clean channel list |
condarc-default-channels |
error |
.condarc default_channels: entries pointing at repo.anaconda.com |
implicit-defaults |
warn |
a channel list without - nodefaults, so conda still adds the channels from your conda configuration |
mixed-with-conda-forge |
warn |
conda-forge listed next to an Anaconda channel |
Why a clean-looking file still fails
Anaconda's Terms of Service require a paid licence for organisations with 200 or more people that use the defaults channel. The anaconda channel on anaconda.org is a mirror of defaults and carries the same terms. conda-forge, bioconda and other community channels are free.
Three traps a quick read misses:
- Channel pins.
defaults::pandas in dependencies: downloads from Anaconda even if channels: only lists conda-forge.
- Implicit defaults.
conda env create adds the channels from your conda configuration after the file's own list. Miniconda and Anaconda installers configure defaults there. Only - nodefaults stops it.
- CI prompts. Anaconda Distribution 2025.06-0 and later ship the conda-anaconda-tos plugin: the channels repo.anaconda.com/pkgs/main, pkgs/r and pkgs/msys2 need
conda tos accept (or CONDA_PLUGINS_AUTO_ACCEPT_TOS) before a non-interactive build can use them.
Worked example
_fixtures/dirty.yml (a churn-model environment) gives 6 findings:
L3 defaults-channel - defaults
L4 anaconda-channel - anaconda
L5 repo-anaconda-url - https://repo.anaconda.com/pkgs/r
L6 pkgs-channel-name - pkgs/msys2
L9 channel-pinned-dependency - pkgs/main::numpy=1.26
L10 channel-pinned-dependency - defaults::pandas
The fixed file lists - conda-forge and - nodefaults, pins conda-forge::pandas, and gives 0 findings.
Files
It runs on environment*.yml, environment*.yaml, .condarc and condarc. Findings show in the Problems panel with the line number, the reason and the conda-forge fix. Nothing leaves your machine.
Free and full version
Free: every finding for the open file, no key. Full version: one scan of every environment file and .condarc in the workspace, exported as a licence-audit report you keep. A web version of the same engine runs at the hub link above.
Not legal advice: whether your organisation is licensed is between you and Anaconda. This tool shows which lines reach Anaconda's repository.
