doc: update CONTRIBUTING.md

CONTRIBUTING.md

@@ -57,25 +57,44 @@ See [doc/contributors/index.md](./doc/contributors/index.md) for more informatio
 
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+## PR Standards
+
+We expect the following from pull requests (it makes things easier):
+- If you're closing an issue, please reference that issue in the PR description
+- Avoid whitespace changes
+- No regressions for "appspace" (Puter apps)
+
+<br>
+
 ## Commit Messages
 
-Use the imperative, as is the convention in the Linux kernel:
+**Note:** we will squash-merge some PRs so they follow . Large PRs should follow conventional commits also. The instructions below are outdated but suitable for most PRs.
+
+### Conventional Commits
+We use [Conventional Commits](https://www.conventionalcommits.org/en/v1.0.0/) with the following prefixes:
+- `fix:` for bug fixes
+- `dev:` instead of `refactor:`; covers more basis
+- `tweak:` for small updates
+- `sync:` when updating data from another source
+- `feat:` for a commit that first introduces a new feature
+
+Commit messages after the prefix should use the imperative (the same convention used in the repo for Linux, which Git was built for):
 
-- correct: `Improve performance of readdir`
-- incorrect: `Improved readdir`
-- incorrect: `Improving readdir`
+- correct: `dev: improve performance of readdir`
+- incorrect: `dev: improved readdir`
+- incorrect: `dev: improving readdir`
 
 We have the following exceptions to this rule:
 - If the commit message is in _past tense_, it's a shorthand for the following:
-  - `Apply changes that would be applied after one had <past tense message>`
+  - `dev: apply changes that would be applied after one had <past tense message>`
 - If the commit message is in _present tense_, it's shorthand for the following:
-  - `Apply changes that would be applied after <present-tense message>`
+  - `dev: apply changes that would be applied after <present-tense message>`
 
 For example, the following are correct:
-- `Improved readdir`
-  - interpret this as: `Apply changes that would be applied after one had improved readdir`
-- `Improving readdir`
-  - interpret this as: `Apply changes that would be applied after improving readdir`
+- `dev: improved readdir`
+  - interpret this as: `dev: apply changes that would be applied after one had improved readdir`
+- `dev: improving readdir`
+  - interpret this as: `dev: apply changes that would be applied after improving readdir`
 
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