---
id: colcon-defaults
version: "0.2.9"
license: Apache License, Version 2.0
license_treatment: permissive
maintenance: active
---

# colcon-defaults — Extension for colcon to read defaults from a config file.

License: permissive · Maintenance: active · Downloads: 183.0K/mo

## What it is and what it does

colcon-defaults is a plugin for the colcon build system that reads default values for command-line arguments from a YAML configuration file. Instead of typing the same flags every time you run colcon build or other colcon commands, you define your defaults once in a configuration file and the plugin applies them automatically on each invocation.

The package depends on colcon-core (the plugin framework) and PyYAML (for parsing the configuration file). It targets developers working with colcon-based build systems who want to reduce repetitive typing and standardize build parameters across a team or project. The plugin integrates transparently into the colcon command pipeline.

Use it for:

- Set default build profiles, parallelism levels, or output directories once in a config file instead of repeating them on every colcon build invocation.
- Standardize build flags across a development team by committing a shared defaults.yaml to version control.
- Reduce command-line clutter in CI/CD pipelines by moving common arguments to a persistent configuration.
- Override default colcon behavior for specific workspaces without modifying shell aliases or wrapper scripts.

## Worth the install?

AI-flagged interpretation of the facts above — verify before relying.

Extends colcon to load default command-line argument values from a YAML configuration file, reducing repetitive command typing in build workflows.

Yes, if you use colcon regularly and find yourself repeating the same command-line flags. The plugin is lightweight, actively maintained, and has no security vulnerabilities. Install it as part of your colcon ecosystem if you want to streamline repetitive build commands; skip it if you rarely use colcon or prefer explicit command lines.

## Install

pip install colcon-defaults
uv add colcon-defaults
poetry add colcon-defaults

## Installing colcon-defaults

Before you install: Low friction install with only two runtime dependencies (colcon-core and PyYAML). Active maintenance with a recent commit in May 2026, though the repository has minimal stars.

License in practice: Apache License 2.0 is permissive, allowing use in commercial and private projects with minimal restrictions.

Quickstart:

pip install colcon-defaults

# Create ~/.colcon/defaults.yaml with your default arguments
# Then use colcon normally; defaults are applied automatically
colcon build

Requires colcon-core to be installed; this is a plugin extension, not a standalone tool.

Verify before relying:

- Whether the defaults.yaml format and location are documented sufficiently for new users.
- Performance impact of loading defaults on each colcon invocation.
- Compatibility with all colcon subcommands or specific limitations.

## Package facts

- License: Apache License, Version 2.0 (permissive)
- Python support: supports_current
- Install friction: low
- Maintenance: active
- Downloads: 183.0K/month (top 15,000 on PyPI)
- Known vulnerabilities: none known

## Tags

colcon defaults configuration, colcon command line defaults, colcon config file arguments, colcon yaml defaults, colcon build tool configuration, colcon-plugin, build-configuration

[View on SkillFed](https://skillfed.io/packages/colcon-defaults) · [View on PyPI](https://pypi.org/project/colcon-defaults/)