diff --git a/pyproject.toml b/pyproject.toml
index 954a3cd..942dc13 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -5,7 +5,6 @@ build-backend = "setuptools.build_meta"
 [project]
 name = "dkpro-cassis"
 version = "0.10.0-dev"
-dynamic = ["dependencies", "optional-dependencies"]
 requires-python = ">=3.8"
 authors = [ { name = "The DKPro cassis team" } ]
 maintainers = [ { name = "Richard Eckart de Castilho" } ]
@@ -27,11 +26,35 @@ classifiers = [
     "Topic :: Scientific/Engineering :: Human Machine Interfaces",
     "Topic :: Text Processing :: Linguistic"
 ]
+dependencies = [
+    "lxml~=4.9.1",
+    "attrs>=21.2,<24",
+    "sortedcontainers~=2.4",
+    "toposort~=1.7",
+    "more-itertools~=8.12",
+    "deprecation~=2.1",
+    "importlib_resources~=5.4"
+]
 
-[tool.setuptools.dynamic]
-dependencies = { file = ["requirements.in"] }
-optional-dependencies.dev = { file = ["requirements-dev.in"] }
-optional-dependencies.doc = { file = ["requirements-dev.in"] }
+[project.optional-dependencies]
+dev = [
+    "pytest~=7.2",
+    "tox~=3.24",
+    "lxml-asserts~=0.1",
+    "pytest-lazy-fixture~=0.6",
+    "pytest-cov~=3.0",
+    "codecov~=2.1",
+    "rstcheck~=3.3",
+    "docutils~=0.20,!=0.21.*",
+    "ruff~=0.4.3",
+    "pip-tools~=7.4.1"
+]
+doc = [
+    "sphinx",
+    "sphinx-autodoc-typehints",
+    "sphinx-rtd-theme",
+    "docutils~=0.20,!=0.21.*"
+]
 
 [project.urls]
 Homepage = "https://dkpro.github.io"
diff --git a/requirements-dev.in b/requirements-dev.in
deleted file mode 100644
index bd96785..0000000
--- a/requirements-dev.in
+++ /dev/null
@@ -1,10 +0,0 @@
-pytest~=7.2
-tox~=3.24
-lxml-asserts~=0.1
-pytest-lazy-fixture~=0.6
-pytest-cov~=3.0
-codecov~=2.1
-rstcheck~=3.3
-docutils~=0.20,!=0.21.*
-ruff~=0.4.3
-pip-tools~=7.4.1
diff --git a/requirements-doc.in b/requirements-doc.in
deleted file mode 100644
index fd121cf..0000000
--- a/requirements-doc.in
+++ /dev/null
@@ -1,4 +0,0 @@
-sphinx
-sphinx-autodoc-typehints
-sphinx-rtd-theme
-docutils~=0.20,!=0.21.*
diff --git a/requirements-doc.txt b/requirements-doc.txt
index 203fd21..97998ee 100644
--- a/requirements-doc.txt
+++ b/requirements-doc.txt
@@ -4,113 +4,82 @@
 #
 #    pip-compile --extra=doc --output-file=requirements-doc.txt pyproject.toml
 #
+alabaster==0.7.16
+    # via sphinx
 attrs==23.2.0
     # via dkpro-cassis (pyproject.toml)
-build==1.2.1
-    # via pip-tools
+babel==2.15.0
+    # via sphinx
 certifi==2024.2.2
     # via requests
 charset-normalizer==3.3.2
     # via requests
-click==8.1.7
-    # via pip-tools
-codecov==2.1.13
-    # via dkpro-cassis (pyproject.toml)
-coverage[toml]==7.5.1
-    # via
-    #   codecov
-    #   pytest-cov
 deprecation==2.1.0
     # via dkpro-cassis (pyproject.toml)
-distlib==0.3.8
-    # via virtualenv
 docutils==0.20.1
     # via
     #   dkpro-cassis (pyproject.toml)
-    #   rstcheck
-exceptiongroup==1.2.1
-    # via pytest
-filelock==3.14.0
-    # via
-    #   tox
-    #   virtualenv
+    #   sphinx
+    #   sphinx-rtd-theme
 idna==3.7
     # via requests
+imagesize==1.4.1
+    # via sphinx
 importlib-metadata==7.1.0
-    # via build
+    # via sphinx
 importlib-resources==5.13.0
     # via dkpro-cassis (pyproject.toml)
-iniconfig==2.0.0
-    # via pytest
+jinja2==3.1.4
+    # via sphinx
 lxml==4.9.4
-    # via
-    #   dkpro-cassis (pyproject.toml)
-    #   lxml-asserts
-lxml-asserts==0.1.2
     # via dkpro-cassis (pyproject.toml)
+markupsafe==2.1.5
+    # via jinja2
 more-itertools==8.14.0
     # via dkpro-cassis (pyproject.toml)
 packaging==24.0
     # via
-    #   build
     #   deprecation
-    #   pytest
-    #   tox
-pip-tools==7.4.1
+    #   sphinx
+pygments==2.18.0
+    # via sphinx
+requests==2.31.0
+    # via sphinx
+snowballstemmer==2.2.0
+    # via sphinx
+sortedcontainers==2.4.0
     # via dkpro-cassis (pyproject.toml)
-platformdirs==4.2.1
-    # via virtualenv
-pluggy==1.5.0
-    # via
-    #   pytest
-    #   tox
-py==1.11.0
-    # via tox
-pyproject-hooks==1.1.0
-    # via
-    #   build
-    #   pip-tools
-pytest==7.4.4
+sphinx==7.3.7
     # via
     #   dkpro-cassis (pyproject.toml)
-    #   pytest-cov
-    #   pytest-lazy-fixture
-pytest-cov==3.0.0
-    # via dkpro-cassis (pyproject.toml)
-pytest-lazy-fixture==0.6.3
-    # via dkpro-cassis (pyproject.toml)
-requests==2.31.0
-    # via codecov
-rstcheck==3.5.0
+    #   sphinx-autodoc-typehints
+    #   sphinx-rtd-theme
+    #   sphinxcontrib-jquery
+sphinx-autodoc-typehints==2.1.0
     # via dkpro-cassis (pyproject.toml)
-ruff==0.4.3
-    # via dkpro-cassis (pyproject.toml)
-six==1.16.0
-    # via tox
-sortedcontainers==2.4.0
+sphinx-rtd-theme==2.0.0
     # via dkpro-cassis (pyproject.toml)
+sphinxcontrib-applehelp==1.0.8
+    # via sphinx
+sphinxcontrib-devhelp==1.0.6
+    # via sphinx
+sphinxcontrib-htmlhelp==2.0.5
+    # via sphinx
+sphinxcontrib-jquery==4.1
+    # via sphinx-rtd-theme
+sphinxcontrib-jsmath==1.0.1
+    # via sphinx
+sphinxcontrib-qthelp==1.0.7
+    # via sphinx
+sphinxcontrib-serializinghtml==1.1.10
+    # via sphinx
 tomli==2.0.1
-    # via
-    #   build
-    #   coverage
-    #   pip-tools
-    #   pytest
-    #   tox
+    # via sphinx
 toposort==1.10
     # via dkpro-cassis (pyproject.toml)
-tox==3.28.0
-    # via dkpro-cassis (pyproject.toml)
 urllib3==2.2.1
     # via requests
-virtualenv==20.26.1
-    # via tox
-wheel==0.43.0
-    # via pip-tools
 zipp==3.18.1
     # via
     #   importlib-metadata
     #   importlib-resources
-
-# The following packages are considered to be unsafe in a requirements file:
-# pip
-# setuptools
diff --git a/requirements.in b/requirements.in
deleted file mode 100644
index 6c9f508..0000000
--- a/requirements.in
+++ /dev/null
@@ -1,7 +0,0 @@
-lxml~=4.9.1
-attrs>=21.2,<24
-sortedcontainers~=2.4
-toposort~=1.7
-more-itertools~=8.12
-deprecation~=2.1
-importlib_resources~=5.4