diff --git a/CODE_OF_CONDUCT.md b/CODE_OF_CONDUCT.md
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+# Repopack Contributor Covenant Code of Conduct
+
+## Our Pledge
+
+In the interest of fostering an open and welcoming environment, we as
+contributors and maintainers pledge to making participation in our project and
+our community a harassment-free experience for everyone, regardless of age, body
+size, disability, ethnicity, sex characteristics, gender identity and expression,
+level of experience, education, socio-economic status, nationality, personal
+appearance, race, religion, or sexual identity and orientation.
+
+## Our Standards
+
+Examples of behavior that contributes to creating a positive environment
+include:
+
+* Using welcoming and inclusive language
+* Being respectful of differing viewpoints and experiences
+* Gracefully accepting constructive criticism
+* Focusing on what is best for the community
+* Showing empathy towards other community members
+
+Examples of unacceptable behavior by participants include:
+
+* The use of sexualized language or imagery and unwelcome sexual attention or
+ advances
+* Trolling, insulting/derogatory comments, and personal or political attacks
+* Public or private harassment
+* Publishing others' private information, such as a physical or electronic
+ address, without explicit permission
+* Other conduct which could reasonably be considered inappropriate in a
+ professional setting
+
+## Our Responsibilities
+
+Project maintainers are responsible for clarifying the standards of acceptable
+behavior and are expected to take appropriate and fair corrective action in
+response to any instances of unacceptable behavior.
+
+Project maintainers have the right and responsibility to remove, edit, or
+reject comments, commits, code, wiki edits, issues, and other contributions
+that are not aligned to this Code of Conduct, or to ban temporarily or
+permanently any contributor for other behaviors that they deem inappropriate,
+threatening, offensive, or harmful.
+
+## Scope
+
+This Code of Conduct applies both within project spaces and in public spaces
+when an individual is representing the project or its community. Examples of
+representing a project or community include using an official project e-mail
+address, posting via an official social media account, or acting as an appointed
+representative at an online or offline event. Representation of a project may be
+further defined and clarified by project maintainers.
+
+## Enforcement
+
+Instances of abusive, harassing, or otherwise unacceptable behavior may be
+reported by contacting the project team at [koukun0120@gmail.com](mailto:koukun0120@gmail.com). All
+complaints will be reviewed and investigated and will result in a response that
+is deemed necessary and appropriate to the circumstances. The project team is
+obligated to maintain confidentiality with regard to the reporter of an incident.
+Further details of specific enforcement policies may be posted separately.
+
+Project maintainers who do not follow or enforce the Code of Conduct in good
+faith may face temporary or permanent repercussions as determined by other
+members of the project's leadership.
+
+## Attribution
+
+This Code of Conduct is adapted from the [Contributor Covenant][homepage], version 1.4,
+available at [https://www.contributor-covenant.org/version/1/4/code-of-conduct.html](https://www.contributor-covenant.org/version/1/4/code-of-conduct.html)
+
+[homepage]: https://www.contributor-covenant.org
+
+For answers to common questions about this code of conduct, see
+[https://www.contributor-covenant.org/faq](https://www.contributor-covenant.org/faq)
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
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+# Contribution Guide
+
+Contributions are welcome! We appreciate your help in making repopack better.
+You can contribute in the following ways:
+
+- Create an Issue - Propose a new feature or report a bug.
+- Pull Request - Fix a bug, add a feature, or improve documentation.
+- Share - Share your thoughts about repopack on blogs, social media, or in tech communities.
+- Use repopack in your projects - Practical usage often leads to valuable feedback and improvements.
+
+Note:
+repopack is maintained by Yamadashy ([@yamadashy](https://github.com/yamadashy)). While we welcome contributions, please understand that not all suggestions may be accepted, especially if they don't align with the project's goals or coding style.
+
+## Installing dependencies
+
+The `yamadashy/repopack` project uses [npm](https://www.npmjs.com/) as its package manager. Developers should have Node.js and npm installed.
+
+After that, please install the dependencies:
+
+```bash
+npm install
+```
+
+## Pull Requests
+
+Before submitting a Pull Request, please ensure:
+
+1. Your code passes all tests: Run `npm run test`
+2. Your code adheres to our linting standards: Run `npm run lint`
+3. You have updated relevant documentation (especially README.md) if you've added or changed functionality.
+
+## Local Development
+
+To set up Repopack for local development:
+
+```bash
+git clone https://github.com/yamadashy/repopack.git
+cd repopack
+npm install
+```
+
+To run Repopack locally:
+
+```bash
+npm run cli-run
+```
+
+## Coding Style
+
+We use [Biome](https://biomejs.dev/) for linting and formatting. Please make sure your code follows the style guide by running:
+
+```bash
+npm run lint
+```
+
+## Testing
+
+We use [Vitest](https://vitest.dev/) for testing. To run the tests:
+
+```bash
+npm run test
+```
+
+For test coverage:
+
+```bash
+npm run test-coverage
+```
+
+## Documentation
+
+When adding new features or making changes, please update the relevant documentation in the README.md file.
+
+## Releasing
+
+Releasing new versions is handled by the project maintainer. If you believe a new release is needed, please open an issue to discuss it.
+
+Thank you for contributing to Repopack!
diff --git a/README.md b/README.md
index 61743705b..5f7e2c044 100644
--- a/README.md
+++ b/README.md
@@ -489,5 +489,11 @@ By default, Repopack's security check feature is enabled. You can disable it by
 
 
 
+## Contribution
+
+See [Contributing Guide](CONTRIBUTING.md).
+
+
+
 ## 📜 License
 MIT