diff --git a/.github/workflows/checks.yml b/.github/workflows/checks.yml
new file mode 100644
index 0000000..d27a2f0
--- /dev/null
+++ b/.github/workflows/checks.yml
@@ -0,0 +1,32 @@
+name: Checks
+on:
+  push:
+    branches: [main, features]
+  pull_request:
+    branches: [main, features]
+
+jobs:
+  lint:
+    name: Code Style
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v5
+    - uses: actions/setup-python@v6
+      with:
+        python-version: 3.x
+    - uses: psf/black@stable
+
+  poetry-check:
+    runs-on: ubuntu-latest
+
+    name: Poetry
+    steps:
+      - uses: actions/checkout@v7
+      - uses: actions/setup-python@v6
+        with:
+          python-version: '3.x'
+      - run: |
+          pip install -U pip poetry
+          poetry install
+      - run: poetry check --strict
diff --git a/.github/workflows/pr.yml b/.github/workflows/pr.yml
new file mode 100644
index 0000000..5d69422
--- /dev/null
+++ b/.github/workflows/pr.yml
@@ -0,0 +1,18 @@
+name: Pull Request
+
+on:
+  pull_request:
+    types:
+      - opened
+      - edited
+      - synchronize
+
+jobs:
+  semantic-pr:
+    name: Validate PR title
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: amannn/action-semantic-pull-request@v6
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
diff --git a/.github/workflows/prchecks.yml b/.github/workflows/prchecks.yml
deleted file mode 100644
index 51a0a08..0000000
--- a/.github/workflows/prchecks.yml
+++ /dev/null
@@ -1,30 +0,0 @@
-name: Pull Request Checks
-
-on:
-  pull_request:
-    branches: [main, features]
-
-jobs:
-  semantic-pr:
-    name: Semantic Pull Request
-    runs-on: ubuntu-latest
-    strategy:
-      fail-fast: false
-
-    steps:
-      - uses: amannn/action-semantic-pull-request@v6
-        env:
-          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-
-  lint:
-    name: Code Style
-    runs-on: ubuntu-latest
-    strategy:
-      fail-fast: false
-
-    steps:
-    - uses: actions/checkout@v5
-    - uses: actions/setup-python@v6
-      with:
-        python-version: 3.x
-    - uses: psf/black@stable
diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 6deb5ab..3ecd1a1 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -18,9 +18,6 @@ jobs:
           - macos-latest
           - windows-latest
         python_version:
-          - '3.8'
-          - '3.9'
-          - '3.10'
           - '3.11'
           - '3.12'
           - '3.13'
diff --git a/Makefile b/Makefile
index 275b019..dda0e73 100644
--- a/Makefile
+++ b/Makefile
@@ -1,5 +1,5 @@
 black:
-	poetry run black kosmorrolib
+	poetry run black kosmorrolib tests.py
 
 .PHONY: tests
 tests: doctests
diff --git a/pyproject.toml b/pyproject.toml
index 1e7b676..ec19069 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,7 +1,9 @@
-[tool.poetry]
+[project]
 name = "kosmorrolib"
 version = "1.0.13"
-authors = ["Jérôme Deuchnord <jerome@deuchnord.fr>"]
+authors = [
+    { name = "Jérôme Deuchnord", email = "jerome@deuchnord.fr" }
+]
 homepage = "https://kosmorro.space/lib"
 repository = "https://github.com/Kosmorro/lib"
 documentation = "https://kosmorro.space/lib/doc"
@@ -10,6 +12,14 @@ license = "AGPL-3.0-or-later"
 description = "A library to computes the ephemerides."
 readme = "README.md"
 
+requires-python = "^3.11"
+dependencies = [
+    "skyfield (>=1.49,<2.0)",
+    "numpy (>=2.3,<3.0)",
+    "skyfield-data (>=7.0.0)",
+    "python-dateutil (>=2.8,<3.0)"
+]
+
 classifiers = [
     "Development Status :: 5 - Production/Stable",
     "Topic :: Scientific/Engineering :: Astronomy",
@@ -18,23 +28,11 @@ classifiers = [
     "Intended Audience :: Education",
 ]
 
-[tool.poetry.dependencies]
-python = "^3.8"
-skyfield = "^1.49"
-numpy = [
-    { version = "<1.25", python = "3.8.*" },
-    { version = "<2.1", python = "3.9.*" },
-    { version = "<2.3", python = "3.10.*" },
-    { version = "^2.3", python = ">=3.11" },
-]
-skyfield-data = "*"
-python-dateutil = "^2.8"
-
 [tool.poetry.group.dev.dependencies]
-black = ">23.1,<25.0"
+black = ">=23.1"
 parameterized = "^0.9.0"
-coverage = "^6.1.2"
-coveralls = "^3.3.1"
+coverage = ">=6.1"
+coveralls = ">=3.3"
 
 [build-system]
 requires = ["poetry-core>=1.0.0"]
diff --git a/tests.py b/tests.py
index 22ee4a3..ad51124 100644
--- a/tests.py
+++ b/tests.py
@@ -4,13 +4,12 @@
 
 from kosmorrolib import *
 
-
 if __name__ == "__main__":
     failures = 0
     tests = 0
 
     for module in [events, ephemerides, model]:
-        (f, t) = testmod(module, optionflags=NORMALIZE_WHITESPACE)
+        f, t = testmod(module, optionflags=NORMALIZE_WHITESPACE)
         failures += f
         tests += t