FEAT: Contributing

- added CONTRIBUTING.md

Signed-off-by: Aternus <kiril@atern.us>

CONTRIBUTING.md

@@ -1,7 +1,75 @@
 # Welcome
 
-Welcome to the `csv-to-xlsx` project. Please read the chapters below carefully to understand how contributing to this project works.
+Welcome to the `csv-to-xlsx` project.
 
-# How CI/CD Works
+Please read the chapters below carefully to understand how contributing to this
+project works.
+
+# Contributing Code
+
+This is a practical guide on how to contribute code (features/bugfixes) to this
+project.
+
+For more indepth explanations about each step feel free to search online.
+
+1. Clone the repo to your computer:
+   `git clone git@github.com:Aternus/csv-to-xlsx.git`
+2. If you're using JetBrain's IntelliJ series of IDE, the setup of your IDE
+   should be automatic.
+
+   If not, set your IDE so that you run Prettier and ESLint on each save.
+
+   Husky should take care of running unit tests after each commit.
+
+   These steps are enforced by the PR so please don't waste time (and resources)
+   ignoring git hooks.
+
+3. Create a new branch: `git checkout -b feat-third-eye`
+4. Contribute code, make sure you've added the description of your work to
+   `CHANGELOG.md`. We use `semver`.
+
+   If there is no new version tag in that file (e.g. the npmjs version is 1.0.0
+   and the changelog last version is 1.0.0), create a new tag (i.e. 1.0.1 if
+   your changes are patch, 1.1.0 if minor, 2.0.0 if major).
+
+5. `git commit`, `git push`
+6. Create PR. If you're not ready for a review yet, mark it as `Draft`
+7. When you're ready for review, assign a reviewer (e.g. `aternus`) and un-draft
+   the PR.
+8. If your PR doesn't pass the automatic checks it will be ignored.
+9. After a successful review, merge the PR.
 
 # Creating a Release
+
+Once the content for the release has been finalized (i.e. all PRs merged,
+`CHANGELOG.md` has the next release version and release notes) it's time to
+create a release for `npmjs.com` and generate binaries.
+
+1. Go to Releases
+2. Press on "Draft a new Release"
+3. Specify a new tag that corresponds to the tag present in the `CHANGELOG.md`
+   and release notes.
+4. The release's title should include the version as the first thing followed by
+   a colon and the major change in this release (e.g.
+   `v1.1.0: Added Support for the Third Eye`)
+5. In most cases it's not necessary to write any additional notes as you'll get
+   the diff which includes the release notes from `CHANGELOG.md`
+6. Make sure "set as the latest release" is selected.
+7. Press on "Publish Release"
+
+# How CI/CD Works
+
+## Validate
+
+1. A new PR triggers the `validate` workflow which lints the code and runs tests
+   on all platforms we should support.
+2. If validation fails, you won't be able to merge the PR.
+3. If integration (merge to `master`) fails, the "validation badge" will be
+   marked red on the main page of the project.
+
+   👀 Keep an eye for it to ensure your PR merge didn't break the project.
+
+## Release
+
+1. A publishing of a Release triggers the `release` workflow which creates
+   binaries and publishes the package to `npmjs.com`