diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 120000
index 0000000..41c198d
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1 @@
+docs/changelog/0.3.0.md
\ No newline at end of file
diff --git a/docs/changelog/0.3.0.md b/docs/changelog/0.3.0.md
new file mode 100644
index 0000000..1502b84
--- /dev/null
+++ b/docs/changelog/0.3.0.md
@@ -0,0 +1,6 @@
+- Refactored core models from `dataclass` to Pydantic across active entities (`Base`, `Device`, `Control`, `Capability`, topic models, and concrete control types like `Switch`, `Climate`, `Sensor`, etc.).
+- Replaced dataclass-specific field metadata (`metadata=dict(exclude=True)`, `field(...)`, `__post_init__`) with native Pydantic patterns (`Field(...)`, `model_post_init`, class inheritance from `corio.dm.Base`).
+- Updated parent/back-reference handling to follow the parent-typing pattern, including explicit in-`__init__` imports for forward references (e.g. `Device.parent: ClientHaco | None`).
+- Reworked `Base.model_dump()` to preserve discovery behavior by merging class `DATA`, defaulting to `exclude_none=True`, and excluding runtime extra attributes so dynamic callbacks do not leak into HA announce payloads.
+- Cleaned up dataclass leftovers by removing the unused `Metadata` helper from `haco/utils.py` and simplifying related imports.
+- Added packaging metadata and testing support updates: `pyproject.toml` project metadata/uv source config, `setup.py` test extras (`pytest`, `pytest-cov`), and initial `haco/tests` package scaffolding.
diff --git a/haco/meta.json b/haco/meta.json
index 9fb18e9..8ab7d3a 100644
--- a/haco/meta.json
+++ b/haco/meta.json
@@ -1,5 +1,5 @@
 {
-    "version": "0.3.0-alpha001",
+    "version": "0.3.0",
     "port": 6,
     "entrypoint": null,
     "base": "python",