Resolve from the CLI

Use conda presto to resolve package specs or environment files without creating an environment.

Resolve inline specs

Choose the channel and target platform explicitly when the result will be used outside the current machine:

conda presto \
  --channel conda-forge \
  --platform linux-64 \
  python=3.13 numpy

Without --platform, conda-presto targets the host platform. Conda combines command-line channels with non-default channels from .condarc. If that effective context has no channels or only defaults, conda-presto uses file channels, then CONDA_PRESTO_CHANNELS.

Resolve an environment file

Pass an environment YAML, requirements file, conda-lock file, or rattler-lock file selected through conda’s environment-specifier registry:

conda presto --file environment.yml --platform linux-64

Specs from repeated --file options and positional specs are combined into one solve:

conda presto \
  --file environment.yml \
  --file development.yml \
  --platform linux-64 \
  pytest

Conda’s explicit-file specifier does not expose the lockfile interface used by this adapter. Explicit files are supported as output, not as --file input.

To ignore channels from conda configuration and use only the command-line channels, pass --override-channels:

conda presto \
  --override-channels \
  --channel conda-forge \
  --file environment.yml

Resolve several platforms

Repeat --platform to solve platforms in parallel:

conda presto \
  --file environment.yml \
  --platform linux-64 \
  --platform osx-arm64 \
  --platform win-64

Native JSON contains one result per platform. A platform that cannot be solved has an error value while successful platforms retain their package records.

conda presto \
  --file environment.yml \
  --platform linux-64 \
  --platform osx-arm64 \
  > solve-result.json

Write an exporter format

Use --format to send successful environments through conda’s exporter registry:

conda presto \
  --file environment.yml \
  --platform linux-64 \
  --platform osx-arm64 \
  --format pixi-lock-v6 \
  > pixi.lock

An exporter cannot represent a partial platform failure. The command exits with an error if any requested platform fails to solve.

List the built-in and plugin-provided formats in Output format reference.

Solve from cached repodata only

Pass conda’s --offline option when the required channel metadata is already present in the local conda cache:

conda presto \
  --offline \
  --channel conda-forge \
  --platform linux-64 \
  zlib

Offline solving fails when the local repodata cache does not cover the request. The internal conda --solver=presto backend does not support offline mode.

Next steps

• Use Transcode lockfiles without solving when both the input and output are lockfiles.

• Use Call the HTTP API to make the same resolve operation over HTTP.

• Look up every option and exit code in CLI reference.

• Adjust target virtual-package defaults through Environment variable reference.