diff --git a/Makefile b/Makefile
index eea28dc..79b63e3 100644
--- a/Makefile
+++ b/Makefile
@@ -78,13 +78,14 @@ sdist bdist bdist_wheel:
 	$(PYTHON3) setup.py $@
 	- rm -v setup.py README
 
+BUILD3 = python3.11 -m build
 .PHONY: build
 build:
 	rm -rf build dist *.egg-info
-	$(MAKE) $(PARALLEL) README setup.py
+	$(MAKE) $(PARALLEL) README
 	# pip install --root=~/local . -v
-	$(PYTHON3) setup.py sdist
-	- rm -v setup.py README
+	$(BUILD3)
+	- rm -v README
 	$(TWINE) check dist/*
 	: $(TWINE) upload dist/*
 
diff --git a/pyproject.toml b/pyproject.toml
index 1ca0241..84b4154 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -12,9 +12,16 @@ readme = { "file" = "README", content-type = "text/markdown" }
 license = { file = "LICENSE" }
 authors = [ { name = "Guido U. Draheim", "email" = "Guido.Draheim@gmx.de" }]
 classifiers = [
-   "License :: APL"
+   "License :: OSI Approved :: Apache Software License",
+   "Operating System :: OS Independent",
+   "Environment :: Console",
+   "Topic :: Text Processing :: Filters",
+   "Typing :: Typed"
 ]
 
+[project.optional-dependencies]
+dev = [ "build" ]
+
 [project.urls]
 homepage = "https://github.com/gdraheim/text_unicoder"
 repository = "https://github.com/gdraheim/text_unicoder.git"