diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 1bd1d1c..6a9d085 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -1,6 +1,6 @@
 name: CI
 
-on: [push]
+on: [push, pull_request]
 
 jobs:
   lint:
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 22ddefc..a283d17 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Changed
+- Updated contribution guidelines.
+- Updated CI workflow to run on Pull Request.
+
 ## [2.0.1] - 2024-07-16
 
 ### Changed
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index d356b13..19b4191 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -36,3 +36,8 @@ Pull requests should be used to propose changes to the codebase. When creating a
 - **All pull requests** should be tagged with the appropriate labels. If you are unsure about which labels to use, please use the `help wanted` label.
 - **All pull requests** should (but are not strictly required to) be accompanied by a description of the alternatives considered when making the changes in the pull request.
 
+All changes must be summarized in [CHANGELOG.md](CHANGELOG.md).
+
+Furthermore, new contributors can add themselves to the list of contributors, present at [CONTRIBUTORS](CONTRIBUTORS).
+
+