diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8b036621..5129ec3c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,7 +3,10 @@
 All notable changes to this project are documented here.
 Breaking changes are listed first in each release.
 
-## [Unreleased]
+## [0.5.0] - Unreleased
+
+Release preparation; the publication date will be recorded when 0.5.0 ships.
+See the [migration guide](README.md#upgrading-from-040) before upgrading.
 
 ### Breaking changes
 
@@ -20,10 +23,11 @@ Breaking changes are listed first in each release.
   nested models. Unknown fields and future enum values remain supported. Use
   `decode_cdp(Model, payload, strict=False)` for the previous tolerant behavior
   that logs a warning and fills missing required fields with `None`.
-- Command timeouts now cover sending and receiving. `CdpClient.default_timeout`
-  is enforced for every transport and inherited by session views. Omit the raw
-  `execute(timeout=...)` argument to inherit the default; pass `None` to disable
-  it. Set `default_timeout=None` to disable the client default entirely.
+- Command timeouts now cover sending and receiving. The
+  `CdpClient(default_timeout=...)` setting is enforced for every transport and
+  inherited by session views. Omit the raw `execute(timeout=...)` argument to
+  inherit the default; pass `None` to disable it. Set `default_timeout=None` to
+  disable the client default entirely.
 - `WebSocketTransport` no longer accepts `default_timeout`; configure it on
   `CdpClient` instead. Standalone transport calls have no deadline unless
   `execute(timeout=seconds)` is specified. Generated methods retain only CDP's
diff --git a/MANIFEST.in b/MANIFEST.in
new file mode 100644
index 00000000..935bac10
--- /dev/null
+++ b/MANIFEST.in
@@ -0,0 +1,2 @@
+include CHANGELOG.md
+include RELEASING.md
diff --git a/README.md b/README.md
index 799a6a6b..d97cb07a 100644
--- a/README.md
+++ b/README.md
@@ -11,12 +11,14 @@ without working with raw JSON messages.
 
 - [Why cdpify?](#why-cdpify)
 - [Installation](#installation)
+- [Upgrading from 0.4.0](#upgrading-from-040)
 - [Quick start](#quick-start)
 - [Supported domains](#supported-domains)
 - [Listening for events](#listening-for-events)
 - [Working with target sessions](#working-with-target-sessions)
 - [Configuration](#configuration)
 - [Development](#development)
+- [Releasing](RELEASING.md)
 - [Resources](#resources)
 
 ## Why cdpify?
@@ -61,10 +63,36 @@ Install the generator dependencies only when regenerating protocol modules:
 pip install "cdpify[generator]"
 ```
 
+## Upgrading from 0.4.0
+
+Version 0.5.0 includes breaking changes. Review these before updating:
+
+| Area | Update for 0.5.0 |
+| --- | --- |
+| Error imports | Replace `cdpify.exceptions` with `cdpify.error`, or import errors from `cdpify`. The old module is removed. |
+| Optional `Any` values | Use `UNSET` to omit a value. `None` now sends JSON `null`; ordinary optional scalar fields still omit `None`. |
+| Required response fields | Generated responses and typed events now raise `CDPDecodeError` when required fields are missing. For tolerant manual decoding, use `decode_cdp(Model, payload, strict=False)`. |
+| Command deadlines | Configure `default_timeout` on `CdpClient`, including for custom transports. The budget covers sending and receiving. `WebSocketTransport` no longer accepts `default_timeout`. |
+| Bounded event buffers | Overflow now raises `CDPEventOverflowError`. Set `overflow="drop_oldest"` to keep lossy buffering. The default buffer remains unlimited. |
+| WebSocket compression | Compression now defaults to `None`. Set `compression="deflate"` to enable it. |
+
+Generated methods accept only CDP parameters. For an individual caller deadline,
+wrap the call in `asyncio.timeout(seconds)`; a CDP parameter named `timeout`
+keeps the units and meaning defined by the protocol. The raw `execute()` method
+accepts a client timeout in seconds: omit it to inherit the client default or
+pass `None` to disable that deadline for the call.
+
+See the [0.5.0 changelog](CHANGELOG.md#050---unreleased) for the complete release
+notes, including raw event streams and performance changes.
+
 ## Quick start
 
 Start Chrome or Chromium with remote debugging enabled, then obtain a page's
-`webSocketDebuggerUrl` from `http://localhost:9222/json`.
+`webSocketDebuggerUrl` from `http://localhost:9222/json`. Launch with
+`--remote-debugging-port=9222 --user-data-dir=<dedicated-profile-directory>`
+and open a tab first. The scripts in [examples](examples) can launch Chrome
+with these options for you, for example `uv run python examples/navigate.py`
+from a development checkout.
 
 ```python
 import asyncio
@@ -72,18 +100,28 @@ import json
 from urllib.request import urlopen
 
 from cdpify import CdpClient
+from cdpify.domains.page import LoadEventFiredEvent
 
 
 def get_websocket_url() -> str:
     with urlopen("http://localhost:9222/json", timeout=5) as response:
-        return json.load(response)[0]["webSocketDebuggerUrl"]
+        return next(
+            target["webSocketDebuggerUrl"]
+            for target in json.load(response)
+            if target.get("type") == "page"
+        )
 
 
 async def main() -> None:
     ws_url = get_websocket_url()
 
     async with CdpClient(ws_url) as client:
-        await client.page.navigate(url="https://example.com")
+        await client.page.enable()
+        async with client.listen(LoadEventFiredEvent) as loaded:
+            navigation = await client.page.navigate(url="https://example.com")
+            if navigation.error_text:
+                raise RuntimeError(navigation.error_text)
+            await loaded.next(timeout=10)
 
         result = await client.runtime.evaluate(
             expression="document.title",
@@ -180,6 +218,7 @@ triggers, subscribe first and then send the command:
 from cdpify.domains.page.events import LoadEventFiredEvent
 
 
+await client.page.enable()
 async with client.listen(LoadEventFiredEvent) as events:
     await client.page.navigate(url="https://example.com")
     await events.next(timeout=10)
@@ -461,6 +500,7 @@ Install the project and its development dependencies with
 uv sync --dev
 uv run pytest
 uv run ruff check . --exclude cdpify/domains
+uv run ruff format --check . --exclude cdpify/domains
 uv run pyright
 uv run python scripts/check_generated.py
 ```
@@ -501,9 +541,13 @@ uv run python -m cdpify.generator
 Generate only selected domains by repeating `--domain`:
 
 ```bash
-uv run python -m cdpify.generator --domain Page --domain Runtime
+uv run python -m cdpify.generator --domain Page --domain Runtime --output-dir build/selected-domains
 ```
 
+Generation replaces the entire output directory, including for selected domains.
+Use a separate `--output-dir` for partial generation to keep the full bundled
+client intact. Selected domains may also reference types from other domains.
+
 Use `--spec-dir` and `--output-dir` to override where downloaded specifications
 and generated modules are written.
 
@@ -516,6 +560,8 @@ once a week and opens a pull request when generated code changes.
 - [Chrome DevTools Protocol documentation](https://chromedevtools.github.io/devtools-protocol/)
 - [Chrome DevTools Protocol repository](https://github.com/ChromeDevTools/devtools-protocol)
 - [Examples](examples)
+- [Changelog and migration notes](CHANGELOG.md)
+- [Release checklist](RELEASING.md)
 
 The code-generation approach was inspired by
 [`cdp-use`](https://github.com/browser-use/cdp-use).
diff --git a/RELEASING.md b/RELEASING.md
new file mode 100644
index 00000000..5964dcd7
--- /dev/null
+++ b/RELEASING.md
@@ -0,0 +1,76 @@
+# Releasing cdpify
+
+Version 0.5.0 is prepared in `pyproject.toml` and `uv.lock`. Its
+[changelog entry](CHANGELOG.md#050---unreleased) remains marked **Unreleased**
+until publication. Release preparation does not publish a package or create a tag.
+
+## Validate the release candidate
+
+Run from the repository root with Python 3.12 or newer:
+
+```bash
+uv sync --dev --extra orjson --locked
+uv run --extra orjson pytest
+uv run ruff check . --exclude cdpify/domains
+uv run ruff format --check . --exclude cdpify/domains
+uv run --extra orjson pyright
+uv run python scripts/check_generated.py
+uv run --extra orjson pytest -m integration -v
+uv run --extra orjson python benchmarks/runtime.py --iterations 1000 --samples 3
+```
+
+The unit suite exercises both JSON backends when `orjson` is installed. The
+integration suite needs Chrome or Chromium; set `CHROME_PATH` if discovery does
+not find it. Confirm that these tests run rather than skip. They launch a
+headless browser with an isolated profile. CI additionally tests Python 3.12,
+3.13 and 3.14 on Ubuntu, Windows and macOS; require those checks to pass on the
+release commit.
+
+Use the bundled-spec drift check above for release validation. The generator
+CLI downloads the latest upstream specs and replaces its output directory;
+review any protocol refresh separately before including it in a release.
+
+Build both distributions and validate their package metadata:
+
+```bash
+uv build
+uvx twine check dist/cdpify-0.5.0-py3-none-any.whl dist/cdpify-0.5.0.tar.gz
+```
+
+Smoke-test the wheel from outside the source checkout in a clean environment.
+Verify that the core imports without extras, that `cdpify.error` and generated
+domains import, and that the wheel contains `cdpify/py.typed` and the generator's
+`templates/*.jinja2` files. Install the `websocket` extra for a real connection
+and the `generator` extra when testing generation. Check the source distribution
+too: it must include the README, changelog and this checklist, and build a wheel
+with the same version and package files.
+
+## Publish when ready
+
+1. Review the [0.4.0 migration guide](README.md#upgrading-from-040) and the
+   complete 0.5.0 changelog against the changes since `v0.4.0`.
+2. Replace `Unreleased` in the 0.5.0 changelog heading with the actual publication
+   date (`YYYY-MM-DD`), remove the release-preparation sentence, and update links
+   to that heading and the release-status paragraph in this checklist. Commit
+   the release changes and merge them into `main` after CI passes.
+3. Rebuild and validate both distributions from that exact commit. Use the
+   explicit 0.5.0 filenames so older files in `dist/` are excluded.
+4. Tag the validated commit and push the tag:
+
+   ```bash
+   git tag -a v0.5.0 -m "Release 0.5.0"
+   git push origin v0.5.0
+   ```
+
+5. Publish the artifacts using the project's PyPI credentials:
+
+   ```bash
+   uv publish dist/cdpify-0.5.0-py3-none-any.whl dist/cdpify-0.5.0.tar.gz
+   ```
+
+6. Create a GitHub release for `v0.5.0` using the changelog's 0.5.0 section as
+   release notes, with breaking changes first. Verify the installed version
+   from PyPI in a clean environment with `pip install "cdpify[websocket]==0.5.0"`.
+
+The repository currently has CI and weekly spec-update workflows; neither
+publishes to PyPI. Pushing a tag alone does not publish the package.
diff --git a/pyproject.toml b/pyproject.toml
index 17f2c82c..e75e6cb7 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [project]
 name = "cdpify"
-version = "0.4.0"
+version = "0.5.0"
 description = "A Python client for the Chrome DevTools Protocol (CDP) optimized for DX."
 readme = "README.md"
 requires-python = ">=3.12"
diff --git a/uv.lock b/uv.lock
index 2f9186f9..321fa093 100644
--- a/uv.lock
+++ b/uv.lock
@@ -13,7 +13,7 @@ wheels = [
 
 [[package]]
 name = "cdpify"
-version = "0.4.0"
+version = "0.5.0"
 source = { editable = "." }
 
 [package.optional-dependencies]