diff --git a/.github/workflows/CI.yml b/.github/workflows/CI.yml
index 72a4491..ad7ece7 100644
--- a/.github/workflows/CI.yml
+++ b/.github/workflows/CI.yml
@@ -13,6 +13,11 @@ on:
     tags:
       - "*"
   pull_request:
+    types:
+      - opened
+      - reopened
+      - synchronize
+      - ready_for_review
   workflow_dispatch:
 
 permissions:
diff --git a/.gitignore b/.gitignore
index c8f0442..80b81c0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,6 +3,8 @@
 # Byte-compiled / optimized / DLL files
 __pycache__/
 .pytest_cache/
+.mypy_cache/
+.ruff_cache/
 *.py[cod]
 
 # C extensions
diff --git a/Cargo.lock b/Cargo.lock
index e3c32c2..ba93707 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -22,7 +22,7 @@ checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
 [[package]]
 name = "fastnanoid"
-version = "0.1.1"
+version = "0.3.0"
 dependencies = [
  "pyo3",
  "rand",
diff --git a/Cargo.toml b/Cargo.toml
index ab78d72..b30f79e 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "fastnanoid"
-version = "0.2.2"
+version = "0.3.0"
 edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
diff --git a/README.md b/README.md
index 68dcbfb..6c0dc0d 100644
--- a/README.md
+++ b/README.md
@@ -11,18 +11,46 @@ It works as a drop in replacement for [py-nanoid](https://github.com/puyuan/py-n
 
 It's 2.7x faster than the original.
 
+## When not to use it
+
+If you need the same amount of entropy as uuid, you may as well use uuid and
+base64url encode it:
+
+```python
+import uuid
+from fastnanoid import urlid_to_uuid, uuid_to_urlid
+# say you have a uuid, maybe from your database:
+id_ = uuid.uuid4() # type: uuid.UUID
+# you can encoded it in base64url so it displays as a short string:
+urlid = uuid_to_urlid(id_) # type: str
+# and when you read it back in from the user, you can convert it back to a normal UUID:
+decoded_urlid = urlid_to_uuid(urlid) # type: UUID
+```
+
+This is simpler than using a nanoid which is not compliant with any existing standards.
+If you already have a generated UUID (say from a database),
+this is _much_ faster than generating a new nanoid.
+(If you don't have a UUID, generating one plus encoding it in base64url is about 50% slower than fastnanoid.)
+
+\* these are very simple helper functions, you can easily implement them
+yourself and save a dependency.
+
 ## Contributing
 
 ```sh
 # local env
 python -m venv .venv
 source .venv/bin/activate
-pip install -r requirements.txt
+pip install -r requirements-dev.txt
 # build and use
 maturin develop
 python -c 'import fastnanoid; print(fastnanoid.generate())'
 # test
 cargo test
+pytest
+mypy
+ruff check
+ruff format --check
 ```
 
 ## Credits
diff --git a/benchmarks/README.md b/benchmarks/README.md
index eb16ae5..c52056f 100644
--- a/benchmarks/README.md
+++ b/benchmarks/README.md
@@ -2,5 +2,17 @@
 
 ```sh
 maturin develop --release
-python Benchmarks/benchmarks.py
+python benchmarks/benchmark.py
+```
+
+Results:
+
+```
+$ python benchmarks/benchmark.py
+Generating 1,000,000 IDs
+- nanoid: 2.22s (2.215884291974362e-06 s/id)
+- fastnanoid: 0.86s (8.563055000267923e-07 s/id) - 2.59x faster
+- uuid (generate + base64encode): 1.28s (1.2837962500052527e-06 s/id) - 1.73x faster
+- uuid (generate only): 0.98s (9.750179999973624e-07 s/id) - 2.27x faster
+- uuid (base64encode only): 0.26s (2.631903750007041e-07 s/id) - 8.42x faster
 ```
diff --git a/benchmarks/benchmark.py b/benchmarks/benchmark.py
index b8fd086..39d6b1a 100644
--- a/benchmarks/benchmark.py
+++ b/benchmarks/benchmark.py
@@ -2,13 +2,34 @@
 
 import fastnanoid
 import nanoid
+import uuid
 
 
 if __name__ == "__main__":
     n = 1_000_000
     print(f"Generating {n:,} IDs")
+
+    print("- nanoid: ", end="", flush=True)
     nanotime = timeit(nanoid.generate, number=n)
+    print(f"{nanotime:.2f}s ({nanotime/n} s/id)")
+
+    print("- fastnanoid: ", end="", flush=True)
     fastnanotime = timeit(fastnanoid.generate, number=n)
-    print(f"nanoid: {nanotime:.2f}s ({nanotime/n} s/id)")
-    print(f"fastnanoid: {fastnanotime:.2f}s ({fastnanotime/n} s/id)")
-    print(f"{nanotime/fastnanotime:.2f}x faster")
+    print(
+        f"{fastnanotime:.2f}s ({fastnanotime/n} s/id) - {nanotime/fastnanotime:.2f}x faster"
+    )
+
+    print("- uuid (generate + base64encode): ", end="", flush=True)
+    uuidb64time = timeit(lambda: fastnanoid.uuid_to_urlid(uuid.uuid4()), number=n)
+    print(
+        f"{uuidb64time:.2f}s ({uuidb64time/n} s/id) - {nanotime/uuidb64time:.2f}x faster"
+    )
+
+    print("- uuid (generate only): ", end="", flush=True)
+    uuidtime = timeit(uuid.uuid4, number=n)
+    print(f"{uuidtime:.2f}s ({uuidtime/n} s/id) - {nanotime/uuidtime:.2f}x faster")
+
+    print("- uuid (base64encode only): ", end="", flush=True)
+    _u = uuid.uuid4()
+    uuidtime = timeit(lambda: fastnanoid.uuid_to_urlid(_u), number=n)
+    print(f"{uuidtime:.2f}s ({uuidtime/n} s/id) - {nanotime/uuidtime:.2f}x faster")
diff --git a/pyproject.toml b/pyproject.toml
index 54263c6..c7d07e4 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -7,13 +7,11 @@ name = "fastnanoid"
 description = "A tiny, secure URL-friendly, and fast unique string ID generator for Python, written in Rust."
 readme = "README.md"
 authors = [
-  {name = "Oliver Lambson", email = "oliverlambson@gmail.com"},
-  {name = "Ochir Erkhembayar"},
+    { name = "Oliver Lambson", email = "oliverlambson@gmail.com" },
+    { name = "Ochir Erkhembayar" },
 ]
-maintainers = [
-  {name = "Oliver Lambson", email = "oliverlambson@gmail.com"},
-]
-license = {file = "LICENSE"}
+maintainers = [{ name = "Oliver Lambson", email = "oliverlambson@gmail.com" }]
+license = { file = "LICENSE" }
 requires-python = ">=3.8"
 keywords = ["nanoid"]
 classifiers = [
@@ -43,3 +41,18 @@ Issues = "https://github.com/oliverlambson/fastnanoid/issues"
 features = ["pyo3/extension-module"]
 python-source = "python"
 module-name = "fastnanoid.fastnanoid"
+
+[tool.pytest.ini_options]
+addopts = "--doctest-modules"
+testpaths = ["python", "benchmarks", "tests"]
+
+[tool.mypy]
+files = ["python/**/*.py", "benchmarks/**/*.py", "tests/**/*.py"]
+
+[tool.ruff]
+include = [
+    "pyproject.toml",
+    "python/**/*.py",
+    "benchmarks/**/*.py",
+    "tests/**/*.py",
+]
diff --git a/python/fastnanoid/__init__.py b/python/fastnanoid/__init__.py
index c615fcc..9260bc3 100644
--- a/python/fastnanoid/__init__.py
+++ b/python/fastnanoid/__init__.py
@@ -1,3 +1,4 @@
 from fastnanoid.fastnanoid import generate
+from fastnanoid.uuid import urlid_to_uuid, uuid_to_urlid
 
-__all__ = ["generate"]
+__all__ = ["generate", "urlid_to_uuid", "uuid_to_urlid"]
diff --git a/python/fastnanoid/uuid.py b/python/fastnanoid/uuid.py
new file mode 100644
index 0000000..4bf8da4
--- /dev/null
+++ b/python/fastnanoid/uuid.py
@@ -0,0 +1,28 @@
+import base64
+import uuid
+
+
+def uuid_to_urlid(uuid_: uuid.UUID) -> str:
+    """Convert a UUID to a short URL-safe string.
+
+    >>> import base64
+    >>> import uuid
+    >>> id_ = uuid.UUID('5d98d578-2731-4a4d-b666-70ca16f10aa2')
+    >>> url_id = uuid_to_urlid(id_)
+    >>> print(url_id)
+    XZjVeCcxSk22ZnDKFvEKog
+    """
+    return base64.urlsafe_b64encode(uuid_.bytes).rstrip(b"=").decode("utf-8")
+
+
+def urlid_to_uuid(url: str) -> uuid.UUID:
+    """Convert a base64url encoded UUID string to a UUID.
+
+    >>> import base64
+    >>> import uuid
+    >>> url_id = 'XZjVeCcxSk22ZnDKFvEKog'
+    >>> id_ = urlid_to_uuid(url_id)
+    >>> print(id_)
+    5d98d578-2731-4a4d-b666-70ca16f10aa2
+    """
+    return uuid.UUID(bytes=base64.urlsafe_b64decode(url + "=" * (len(url) % 4)))
diff --git a/requirements-dev.txt b/requirements-dev.txt
index 007a2cd..cc407a9 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -1,3 +1,7 @@
 -e .
 maturin
 nanoid==2.0.0
+pytest
+mypy
+ruff
+types-nanoid
diff --git a/tests/test_fastnanoid.py b/tests/test_fastnanoid.py
new file mode 100644
index 0000000..d721d94
--- /dev/null
+++ b/tests/test_fastnanoid.py
@@ -0,0 +1,6 @@
+from fastnanoid import generate
+
+
+def test_generate():
+    assert len(generate()) == 21
+    assert len(generate(size=10)) == 10