diff --git a/.codecov.yml b/.codecov.yml
new file mode 100644
index 0000000..0fe8f6a
--- /dev/null
+++ b/.codecov.yml
@@ -0,0 +1,33 @@
+coverage:
+  status:
+    project:
+      default:
+        target: auto
+        threshold: 1%
+        informational: true
+    patch:
+      default:
+        target: auto
+        threshold: 1%
+        informational: true
+
+  # Report coverage for all files, even if not touched in PR
+  report:
+    exclude_labels:
+      - "skip-coverage"
+
+comment:
+  layout: "reach,diff,flags,tree"
+  behavior: default
+  require_changes: false
+
+# Files to ignore in coverage
+ignore:
+  - "tests/*"
+  - "**/__pycache__/*"
+  - "**/htmlcov/*"
+  - "setup.py"
+
+# GitHub Checks integration
+github_checks:
+  annotations: true
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index c3a0428..23e5526 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -39,15 +39,14 @@ jobs:
 
       - name: Run tests
         run: |
-          pytest -v --cov=tzst --cov-report=xml
+          pytest --cov=tzst --cov-branch --cov-report=xml
 
       - name: Upload coverage to Codecov
         if: matrix.os == 'ubuntu-latest' && matrix.python-version == '3.12'
         uses: codecov/codecov-action@v5
         with:
-          file: ./coverage.xml
-          flags: unittests
-          name: codecov-umbrella
+          token: ${{ secrets.CODECOV_TOKEN }}
+          slug: xixu-me/tzst
 
   build:
     needs: test
diff --git a/README.md b/README.md
index 68a638a..b784aca 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,6 @@
 # tzst
 
+[![codecov](https://codecov.io/gh/xixu-me/tzst/graph/badge.svg?token=2AIN1559WU)](https://codecov.io/gh/xixu-me/tzst)
 [![CodeQL](https://github.com/xixu-me/tzst/actions/workflows/github-code-scanning/codeql/badge.svg)](https://github.com/xixu-me/tzst/actions/workflows/github-code-scanning/codeql)
 [![CI/CD](https://github.com/xixu-me/tzst/actions/workflows/ci.yml/badge.svg)](https://github.com/xixu-me/tzst/actions/workflows/ci.yml)
 [![PyPI - Version](https://img.shields.io/pypi/v/tzst)](https://pypi.org/project/tzst/)
diff --git a/pyproject.toml b/pyproject.toml
index b013282..1a28810 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -56,7 +56,7 @@ testpaths = ["tests"]
 python_files = ["test_*.py"]
 python_classes = ["Test*"]
 python_functions = ["test_*"]
-addopts = "--cov=tzst --cov-report=term-missing --cov-report=html"
+addopts = "--cov --cov-report=term-missing --cov-report=html"
 markers = ["integration: marks tests as integration tests"]
 
 [tool.ruff]