diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index e0a8c79..70c85a0 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -10,13 +10,13 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Release
-        uses: patrick-kidger/action_update_python_project@v7
+        uses: patrick-kidger/action_update_python_project@v8
         with:
             python-version: "3.11"
             test-script: |
                 cp -r ${{ github.workspace }}/tests ./tests
                 cp ${{ github.workspace }}/pyproject.toml ./pyproject.toml
-                uv sync --extra dev --no-install-project --inexact
+                uv sync --extra tests --no-install-project --inexact
                 uv run --no-sync pytest
             pypi-token: ${{ secrets.pypi_token }}
             github-user: patrick-kidger
diff --git a/.github/workflows/run_tests.yml b/.github/workflows/run_tests.yml
index 318f30a..9d44003 100644
--- a/.github/workflows/run_tests.yml
+++ b/.github/workflows/run_tests.yml
@@ -7,7 +7,7 @@ jobs:
   run-test:
     strategy:
       matrix:
-        python-version: [ "3.11" ]
+        python-version: [ "3.11", "3.13" ]
         os: [ ubuntu-latest ]
       fail-fast: false
     runs-on: ${{ matrix.os }}
@@ -23,11 +23,12 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip
-          python -m pip install '.[dev]'
+          python -m pip install '.[dev,tests]'
 
       - name: Checks with pre-commit
-        uses: pre-commit/action@v3.0.1
+        run: |
+          pre-commit run --all-files
 
       - name: Test with pytest
         run: |
-          python -m pytest
+          pytest
diff --git a/.gitignore b/.gitignore
index 24c78af..080be7a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -14,3 +14,4 @@ examples/multipart_serialised.eqx
 .python-version
 .DS_Store
 .venv
+uv.lock
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 37a665f..34bc32d 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -8,7 +8,7 @@ repos:
         files: ^pyproject\.toml$
         additional_dependencies: ["toml-sort==0.23.1"]
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.6.4
+    rev: v0.13.0
     hooks:
       - id: ruff-format # formatter
         types_or: [python, pyi, jupyter, toml]
@@ -16,7 +16,8 @@ repos:
         types_or: [python, pyi, jupyter, toml]
         args: [--fix]
   - repo: https://github.com/RobertCraigie/pyright-python
-    rev: v1.1.379
+    rev: v1.1.405
     hooks:
       - id: pyright
-        additional_dependencies: [numpy, pytest]
+        additional_dependencies:
+          [pytest]
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
new file mode 100644
index 0000000..9398d7d
--- /dev/null
+++ b/CONTRIBUTING.md
@@ -0,0 +1,40 @@
+# Contributing
+
+Contributions (pull requests) are very welcome! Here's how to get started.
+
+---
+
+**Getting started**
+
+First fork the library on GitHub.
+
+Then clone and install the library:
+
+```bash
+git clone https://github.com/your-username-here/tinyio.git
+cd tinyio
+pip install -e '.[dev]'
+pre-commit install  # `pre-commit` is installed by `pip` on the previous line
+```
+
+---
+
+**If you're making changes to the code:**
+
+Now make your changes. Make sure to include additional tests if necessary.
+
+Next verify the tests all pass:
+
+```bash
+pip install -e '.[tests]'
+pytest  # `pytest` is installed by `pip` on the previous line.
+```
+
+Then push your changes back to your fork of the repository:
+
+```bash
+git push
+```
+
+Finally, open a pull request on GitHub!
+
diff --git a/pyproject.toml b/pyproject.toml
index 60db1cb..e238a4e 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -23,10 +23,14 @@ urls = {repository = "https://github.com/patrick-kidger/tinyio"}
 version = "0.2.0"
 
 [project.optional-dependencies]
-dev = ["pre-commit", "pytest"]
+dev = ["pre-commit"]
+tests = ["pytest"]
 
 [tool.hatch.build]
 include = ["tinyio/*"]
+reportFunctionMemberAccess = false
+reportIncompatibleMethodOverride = true
+reportIncompatibleVariableOverride = false
 
 [tool.pyright]
 include = ["tinyio", "tests"]
@@ -48,5 +52,6 @@ select = ["E", "F", "I001", "UP"]
 
 [tool.ruff.lint.isort]
 combine-as-imports = true
+extra-standard-library = ["typing_extensions"]
 lines-after-imports = 2
 order-by-type = true
diff --git a/tinyio/_core.py b/tinyio/_core.py
index 0d10a87..b08ac6e 100644
--- a/tinyio/_core.py
+++ b/tinyio/_core.py
@@ -167,7 +167,7 @@ def _step(
                     for out_i in out:
                         if isinstance(out_i, Generator):
                             if out_i not in self._results.keys() and out_i not in waiting_on.keys():
-                                if out_i.gi_frame is None:
+                                if out_i.gi_frame is None:  # pyright: ignore[reportAttributeAccessIssue]
                                     todo.coro.throw(_already_finished(out_i))
                                 queue.appendleft(_Todo(out_i, None))
                                 waiting_on[out_i] = []
@@ -184,7 +184,7 @@ def _step(
                             elif out_i in waiting_on.keys():
                                 waiting_on[out_i].append(waiting_for)
                             else:
-                                if out_i.gi_frame is None:
+                                if out_i.gi_frame is None:  # pyright: ignore[reportAttributeAccessIssue]
                                     todo.coro.throw(_already_finished(out_i))
                                 queue.appendleft(_Todo(out_i, None))
                                 waiting_on[out_i] = [waiting_for]