Converting a Conda environment to YAML creates a portable specification file that captures all packages, versions, and channels. This YAML file can recreate the identical environment on any machine with Conda installed — essential for reproducible data science, shared development, and CI/CD deployment.
The Core Command
conda activate myenv conda env export > environment.yml
This exports the active environment to environment.yml in your current directory. The file contains the environment name, all channels in priority order, and every installed package with its exact version and build string.
Cross-Platform Export Without Build Strings
conda env export --no-builds > environment.yml
The –no-builds flag removes platform-specific build hashes, making the file usable on Mac, Linux, and Windows. Version numbers are still pinned — only the platform-specific build identifiers are removed.
Export Only Explicitly Installed Packages
conda env export --from-history > environment.yml
This exports only the packages you explicitly installed, not their auto-resolved dependencies. The result is a much shorter, more maintainable file that works across platforms. The trade-off is that exact sub-dependency versions are not pinned, so the recreated environment may have slightly different minor versions.
Export Without Activating
conda env export -n environment_name > environment.yml
Use the -n flag to export any environment by name without activating it first. This is essential in CI/CD pipelines and automated scripts where interactive activation is not possible.
Recreate From the YAML File
conda env create -f environment.yml
Conda reads the YAML file and installs all listed packages into a new environment with the name specified in the file. To update an existing environment: conda env update -f environment.yml –prune. The –prune flag removes packages not in the YAML file, keeping the environment in sync with the specification.
Best Practices for the Exported YAML
Remove the prefix: line at the bottom before committing to version control — it contains your local installation path and is machine-specific. Validate the YAML structure with Format Pilot YAML formatter if you edit the file manually. Commit the file to your repository so teammates and CI systems can recreate the environment automatically.
Frequently Asked Questions
Should I use .yml or .yaml extension for Conda?
Both work identically. The .yml extension is the Conda convention used in official documentation and most tutorials. The .yaml extension is the full YAML standard file extension. Choose either — conda env create -f accepts both extensions without any configuration change.
How do I update an environment after changing the YAML file?
Use conda env update -f environment.yml instead of creating a new environment. Add –prune to remove packages that are in the existing environment but not in the updated YAML file. This keeps the environment perfectly in sync with the specification without recreating it from scratch.