diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yaml
similarity index 100%
rename from .github/workflows/ci.yml
rename to .github/workflows/ci.yaml
diff --git a/AGENTS.md b/AGENTS.md
index 6927705..d6d6eae 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -80,6 +80,8 @@ pyproject.toml       (Dependencies & tool config)
   `pyproject.toml`, structure, or core logic changes.
 - **Pre-commit Config:** Keep `.pre-commit-config.yaml`
   in sync with CI workflow when test requirements change.
+- **YAML Files:** Use `.yaml` extension for all YAML files
+  (e.g., `.github/workflows/ci.yaml` instead of `.yml`).
 
 ## Workflow Commands
 
diff --git a/AGENTS_MANUAL_CHECKS.md b/AGENTS_MANUAL_CHECKS.md
index aff7c5c..9034417 100644
--- a/AGENTS_MANUAL_CHECKS.md
+++ b/AGENTS_MANUAL_CHECKS.md
@@ -78,6 +78,8 @@ pyproject.toml       (Dependencies & tool config)
 - **Keep Instructions Current:** Update "Tech Stack,"
   "Project Structure," and "Workflow Commands" if
   `pyproject.toml`, structure, or core logic changes.
+- **YAML Files:** Use `.yaml` extension for all YAML files
+  (e.g., `.github/workflows/ci.yaml` instead of `.yml`).
 
 ## Workflow Commands
 
diff --git a/CHANGELOG.md b/CHANGELOG.md
index b1bdcc6..05cc845 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,13 @@ in this file.
 The format is based on
 [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
 
+## [0.1.2] - 2026-07-27 - #12 "Standardize to .yaml"
+
+### Changed
+
+- Renamed CI workflow from `.yml` to `.yaml` for
+- consistent YAML extension usage.
+
 ## [0.1.1] - 2026-07-10 - #11 "Add python prek hooks for git pre-commit"
 
 ### Added
diff --git a/pyproject.toml b/pyproject.toml
index d815bc1..55fa3bc 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [project]
 name = "python-package-template"
-version = "0.1.1"
+version = "0.1.2"
 description = "A simple package using pydantic"
 readme = "README.md"
 requires-python = ">=3.10"
diff --git a/uv.lock b/uv.lock
index 2a5fff2..1414326 100644
--- a/uv.lock
+++ b/uv.lock
@@ -1203,7 +1203,7 @@ wheels = [
 
 [[package]]
 name = "python-package-template"
-version = "0.1.1"
+version = "0.1.2"
 source = { editable = "." }
 dependencies = [
     { name = "pydantic" },