diff --git a/.github/workflows/Bench.yml b/.github/workflows/Bench.yml
index 376305c..ec4cae4 100644
--- a/.github/workflows/Bench.yml
+++ b/.github/workflows/Bench.yml
@@ -37,4 +37,4 @@ jobs:
             --token "${{ secrets.BENCHER_API_TOKEN }}" \
             --adapter python_pytest \
             --err \
-            "pytest --benchmark-json results.json tests/test_bench.py"
+            "pytest --benchmark-json results.json --benchmark-warmup=on --benchmark-warmup-iterations=100 tests/test_bench.py"
diff --git a/.github/workflows/CodSpeed.yml b/.github/workflows/CodSpeed.yml
index 5795eb8..a54d5fe 100644
--- a/.github/workflows/CodSpeed.yml
+++ b/.github/workflows/CodSpeed.yml
@@ -33,7 +33,7 @@ jobs:
       - name: Run benchmarks
         uses: CodSpeedHQ/action@v3
         with:
-          run: uv run pytest tests/ --codspeed
+          run: uv run pytest --benchmark-warmup=on --benchmark-warmup-iterations=100 --codspeed tests/test_bench.py
 
       - name: Minimize uv cache
         run: uv cache prune --ci
diff --git a/README.md b/README.md
index e4f96cb..bf3df17 100644
--- a/README.md
+++ b/README.md
@@ -17,7 +17,7 @@
 >    borders.
 > 2. Rust use lazy init, so first calling will be a little slow.
 > 3. Use about 40MB memory.
-> 4. It's tested under Python 3.9+ but support 3.8+(noqa).
+> 4. It's tested under Python 3.9+.
 > 5. Try it online: <https://ringsaturn.github.io/tzf-web/>
 
 ## Usage
@@ -48,25 +48,25 @@ conda install -c conda-forge tzfpy
 ## Performance
 
 Benchmark runs under
-[`v0.15.3`](https://github.com/ringsaturn/tzfpy/releases/tag/v0.15.3) on my
+[`v0.16.0`](https://github.com/ringsaturn/tzfpy/releases/tag/v0.16.0) on my
 MacBook Pro with Apple M3 Max.
 
 ```bash
-pytest tests/test_bench.py
+pytest --benchmark-warmup=on --benchmark-warmup-iterations=100 tests/test_bench.py 
 ```
 
 ```
------------------------------------------------------------- benchmark: 1 tests ------------------------------------------------------------
-Name (time in ns)                 Min          Max        Mean    StdDev      Median         IQR  Outliers  OPS (Kops/s)  Rounds  Iterations
---------------------------------------------------------------------------------------------------------------------------------------------
-test_tzfpy_random_cities     837.4918  11,183.2982  1,973.3456  833.9543  1,820.9103  1,066.7020  6422;511      506.7536   20000          10
---------------------------------------------------------------------------------------------------------------------------------------------
+----------------------------------------------------------- benchmark: 1 tests -----------------------------------------------------------
+Name (time in ns)                 Min         Max        Mean    StdDev      Median       IQR   Outliers  OPS (Kops/s)  Rounds  Iterations
+------------------------------------------------------------------------------------------------------------------------------------------
+test_tzfpy_random_cities     699.9937  7,175.0022  1,562.1433  646.9249  1,441.6990  833.3940  13716;984      640.1461   41026          10
+------------------------------------------------------------------------------------------------------------------------------------------
 
 Legend:
   Outliers: 1 Standard Deviation from Mean; 1.5 IQR (InterQuartile Range) from 1st Quartile and 3rd Quartile.
   OPS: Operations Per Second, computed as 1 / Mean
-Results (1.95s):
-         4 passed
+Results (1.81s):
+         1 passed
 ```
 
 Or you can view more benchmark results on
diff --git a/pyproject.toml b/pyproject.toml
index c847b5c..339c5b4 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -39,12 +39,8 @@ Documentation = "https://github.com/ringsaturn/tzfpy"
 Issues = "https://github.com/ringsaturn/tzfpy/issues"
 "Source Code" = "https://github.com/ringsaturn/tzfpy"
 
-[tool.maturin]
-# "extension-module" tells pyo3 we want to build an extension module (skips linking against libpython.so)
-features = ["pyo3/extension-module"]
-
-[tool.uv]
-dev-dependencies = [
+[dependency-groups]
+dev = [
   "ruff>=0.7.1",
   "citiespy>=0.6.5",
   "maturin>=1.7.4",
@@ -56,3 +52,7 @@ dev-dependencies = [
   "tzdata>=2024.2",
   "pytest-codspeed>=2.2.1",
 ]
+
+[tool.maturin]
+# "extension-module" tells pyo3 we want to build an extension module (skips linking against libpython.so)
+features = ["pyo3/extension-module"]
diff --git a/tests/test_basic.py b/tests/test_basic.py
new file mode 100644
index 0000000..bbd625b
--- /dev/null
+++ b/tests/test_basic.py
@@ -0,0 +1,18 @@
+from pytest import mark
+from tzfpy import get_tz
+
+
+@mark.parametrize(
+    "lng, lat, tz",
+    [
+        (116.3883, 39.9289, "Asia/Shanghai"),
+        (120.347287, 22.598127, "Asia/Taipei"),
+        (2.3522, 48.8566, "Europe/Paris"),
+        (-0.1276, 51.5074, "Europe/London"),
+        (13.4049, 52.5200, "Europe/Berlin"),
+        (-74.0060, 40.7128, "America/New_York"),
+        (-118.2437, 34.0522, "America/Los_Angeles"),
+    ],
+)
+def test_get_tz(lng, lat, tz):
+    assert get_tz(lng, lat) == tz
diff --git a/tests/test_compatibility.py b/tests/test_compatibility.py
index 094bb9a..7a5aecf 100644
--- a/tests/test_compatibility.py
+++ b/tests/test_compatibility.py
@@ -1,30 +1,26 @@
-from unittest import TestCase, main
-
 from citiespy import all_cities
 from tzfpy import data_version, get_tzs, timezonenames
 
 
-class TestCompatibility(TestCase):
-    def test_with_pytz(self):
-        from pytz import timezone
+def test_with_pytz():
+    from pytz import timezone
+
+    for tz in timezonenames():
+        timezone(tz)
 
-        for tz in timezonenames():
-            timezone(tz)
 
-    def test_with_tzdata(self):
-        from zoneinfo import ZoneInfo
+def test_with_tzdata():
+    from zoneinfo import ZoneInfo
 
-        for tz in timezonenames():
-            ZoneInfo(tz)
+    for tz in timezonenames():
+        ZoneInfo(tz)
 
-    def test_no_empty(self):
-        for city in all_cities():
-            tznames = get_tzs(city.lng, city.lat)
-            self.assertTrue(len(tznames) != 0)
 
-    def test_version_support(self):
-        self.assertTrue(data_version() not in [None, ""])
+def test_no_empty():
+    for city in all_cities():
+        tznames = get_tzs(city.lng, city.lat)
+        assert len(tznames) != 0
 
 
-if __name__ == "__main___":
-    main()
+def test_version_support():
+    assert data_version() not in [None, ""]
diff --git a/uv.lock b/uv.lock
index d8c8684..01fd3cb 100644
--- a/uv.lock
+++ b/uv.lock
@@ -186,6 +186,18 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/b9/f8/feced7779d755758a52d1f6635d990b8d98dc0a29fa568bbe0625f18fdf3/filelock-3.16.1-py3-none-any.whl", hash = "sha256:2082e5703d51fbf98ea75855d9d5527e33d8ff23099bec374a134febee6946b0", size = 16163 },
 ]
 
+[[package]]
+name = "importlib-metadata"
+version = "8.5.0"
+source = { registry = "https://pypi.org/simple" }
+dependencies = [
+    { name = "zipp" },
+]
+sdist = { url = "https://files.pythonhosted.org/packages/cd/12/33e59336dca5be0c398a7482335911a33aa0e20776128f038019f1a95f1b/importlib_metadata-8.5.0.tar.gz", hash = "sha256:71522656f0abace1d072b9e5481a48f07c138e00f079c38c8f883823f9c26bd7", size = 55304 }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/a0/d9/a1e041c5e7caa9a05c925f4bdbdfb7f006d1f74996af53467bc394c97be7/importlib_metadata-8.5.0-py3-none-any.whl", hash = "sha256:45e54197d28b7a7f1559e60b95e7c567032b602131fbd588f1497f47880aa68b", size = 26514 },
+]
+
 [[package]]
 name = "iniconfig"
 version = "2.0.0"
@@ -303,43 +315,45 @@ wheels = [
 
 [[package]]
 name = "pytest-benchmark"
-version = "4.0.0"
+version = "5.1.0"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "py-cpuinfo" },
     { name = "pytest" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/28/08/e6b0067efa9a1f2a1eb3043ecd8a0c48bfeb60d3255006dcc829d72d5da2/pytest-benchmark-4.0.0.tar.gz", hash = "sha256:fb0785b83efe599a6a956361c0691ae1dbb5318018561af10f3e915caa0048d1", size = 334641 }
+sdist = { url = "https://files.pythonhosted.org/packages/39/d0/a8bd08d641b393db3be3819b03e2d9bb8760ca8479080a26a5f6e540e99c/pytest-benchmark-5.1.0.tar.gz", hash = "sha256:9ea661cdc292e8231f7cd4c10b0319e56a2118e2c09d9f50e1b3d150d2aca105", size = 337810 }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/4d/a1/3b70862b5b3f830f0422844f25a823d0470739d994466be9dbbbb414d85a/pytest_benchmark-4.0.0-py3-none-any.whl", hash = "sha256:fdb7db64e31c8b277dff9850d2a2556d8b60bcb0ea6524e36e28ffd7c87f71d6", size = 43951 },
+    { url = "https://files.pythonhosted.org/packages/9e/d6/b41653199ea09d5969d4e385df9bbfd9a100f28ca7e824ce7c0a016e3053/pytest_benchmark-5.1.0-py3-none-any.whl", hash = "sha256:922de2dfa3033c227c96da942d1878191afa135a29485fb942e85dff1c592c89", size = 44259 },
 ]
 
 [[package]]
 name = "pytest-codspeed"
-version = "2.2.1"
+version = "3.0.0"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "cffi" },
     { name = "filelock" },
+    { name = "importlib-metadata", marker = "python_full_version < '3.10'" },
     { name = "pytest" },
+    { name = "rich" },
     { name = "setuptools", marker = "python_full_version >= '3.12'" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/40/6a/ba0b067dba286443a04c9d32ff75ef3bc169617ee347d1a97972ada62665/pytest_codspeed-2.2.1.tar.gz", hash = "sha256:0adc24baf01c64a6ca0a0b83b3cd704351708997e09ec086b7776c32227d4e0a", size = 9163 }
+sdist = { url = "https://files.pythonhosted.org/packages/ba/78/40e613268cce75b11cd35ea9fdc280fb648e2233fc4187c76112377b1869/pytest_codspeed-3.0.0.tar.gz", hash = "sha256:c5b80100ea32dd44079bb2db298288763eb8fe859eafa1650a8711bd2c32fd06", size = 12540 }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/03/0b/e3541064afcf24ed54bcabfa6eb5f8083eb335d5c58c7b5b95bc31127f86/pytest_codspeed-2.2.1-py3-none-any.whl", hash = "sha256:aad08033015f3e6c8c14c8bf0eca475921a9b088e92c98b626bf8af8f516471e", size = 10126 },
+    { url = "https://files.pythonhosted.org/packages/a6/79/fa067436033410ac16e5d14b61b1a5f355688930ca8c6a8c61a52b2cbe0a/pytest_codspeed-3.0.0-py3-none-any.whl", hash = "sha256:ab1b8cb9da72e0d394718333d1abc7bea38524e09fd4854bc70a91abbcdcb20e", size = 15640 },
 ]
 
 [[package]]
 name = "pytest-cov"
-version = "5.0.0"
+version = "6.0.0"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "coverage", extra = ["toml"] },
     { name = "pytest" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/74/67/00efc8d11b630c56f15f4ad9c7f9223f1e5ec275aaae3fa9118c6a223ad2/pytest-cov-5.0.0.tar.gz", hash = "sha256:5837b58e9f6ebd335b0f8060eecce69b662415b16dc503883a02f45dfeb14857", size = 63042 }
+sdist = { url = "https://files.pythonhosted.org/packages/be/45/9b538de8cef30e17c7b45ef42f538a94889ed6a16f2387a6c89e73220651/pytest-cov-6.0.0.tar.gz", hash = "sha256:fde0b595ca248bb8e2d76f020b465f3b107c9632e6a1d1705f17834c89dcadc0", size = 66945 }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/78/3a/af5b4fa5961d9a1e6237b530eb87dd04aea6eb83da09d2a4073d81b54ccf/pytest_cov-5.0.0-py3-none-any.whl", hash = "sha256:4f0764a1219df53214206bf1feea4633c3b558a2925c8b59f144f682861ce652", size = 21990 },
+    { url = "https://files.pythonhosted.org/packages/36/3b/48e79f2cd6a61dbbd4807b4ed46cb564b4fd50a76166b1c4ea5c1d9e2371/pytest_cov-6.0.0-py3-none-any.whl", hash = "sha256:eee6f1b9e61008bd34975a4d5bab25801eb31898b032dd55addc93e96fcaaa35", size = 22949 },
 ]
 
 [[package]]
@@ -405,11 +419,11 @@ wheels = [
 
 [[package]]
 name = "setuptools"
-version = "75.2.0"
+version = "75.3.0"
 source = { registry = "https://pypi.org/simple" }
-sdist = { url = "https://files.pythonhosted.org/packages/07/37/b31be7e4b9f13b59cde9dcaeff112d401d49e0dc5b37ed4a9fc8fb12f409/setuptools-75.2.0.tar.gz", hash = "sha256:753bb6ebf1f465a1912e19ed1d41f403a79173a9acf66a42e7e6aec45c3c16ec", size = 1350308 }
+sdist = { url = "https://files.pythonhosted.org/packages/ed/22/a438e0caa4576f8c383fa4d35f1cc01655a46c75be358960d815bfbb12bd/setuptools-75.3.0.tar.gz", hash = "sha256:fba5dd4d766e97be1b1681d98712680ae8f2f26d7881245f2ce9e40714f1a686", size = 1351577 }
 wheels = [
-    { url = "https://files.pythonhosted.org/packages/31/2d/90165d51ecd38f9a02c6832198c13a4e48652485e2ccf863ebb942c531b6/setuptools-75.2.0-py3-none-any.whl", hash = "sha256:a7fcb66f68b4d9e8e66b42f9876150a3371558f98fa32222ffaa5bced76406f8", size = 1249825 },
+    { url = "https://files.pythonhosted.org/packages/90/12/282ee9bce8b58130cb762fbc9beabd531549952cac11fc56add11dcb7ea0/setuptools-75.3.0-py3-none-any.whl", hash = "sha256:f2504966861356aa38616760c0f66568e535562374995367b4e69c7143cf6bcd", size = 1251070 },
 ]
 
 [[package]]
@@ -452,7 +466,7 @@ tzdata = [
     { name = "tzdata" },
 ]
 
-[package.dev-dependencies]
+[package.dependency-groups]
 dev = [
     { name = "citiespy" },
     { name = "maturin" },
@@ -472,7 +486,7 @@ requires-dist = [
     { name = "tzdata", marker = "extra == 'tzdata'", specifier = ">=2024.2" },
 ]
 
-[package.metadata.requires-dev]
+[package.metadata.dependency-groups]
 dev = [
     { name = "citiespy", specifier = ">=0.6.5" },
     { name = "maturin", specifier = ">=1.7.4" },
@@ -485,3 +499,12 @@ dev = [
     { name = "ruff", specifier = ">=0.7.1" },
     { name = "tzdata", specifier = ">=2024.2" },
 ]
+
+[[package]]
+name = "zipp"
+version = "3.20.2"
+source = { registry = "https://pypi.org/simple" }
+sdist = { url = "https://files.pythonhosted.org/packages/54/bf/5c0000c44ebc80123ecbdddba1f5dcd94a5ada602a9c225d84b5aaa55e86/zipp-3.20.2.tar.gz", hash = "sha256:bc9eb26f4506fda01b81bcde0ca78103b6e62f991b381fec825435c836edbc29", size = 24199 }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/62/8b/5ba542fa83c90e09eac972fc9baca7a88e7e7ca4b221a89251954019308b/zipp-3.20.2-py3-none-any.whl", hash = "sha256:a817ac80d6cf4b23bf7f2828b7cabf326f15a001bea8b1f9b49631780ba28350", size = 9200 },
+]