diff --git a/pyproject.toml b/pyproject.toml
index f06781c..c4ea671 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,8 +1,8 @@
 # https://setuptools.pypa.io/en/latest/userguide/pyproject_config.html
 
 [build-system]
-build-backend = "flit_core.buildapi"
-requires = ["flit_core >=3.2,<4"]
+build-backend = "hatchling.build"
+requires = ["hatchling"]
 
 [project]
 authors = [{name = "gdsfactory", email = "contact@gdsfactory.com"}]
@@ -75,6 +75,12 @@ max = 1.6
 min = 1.5
 num = 1000
 
+[tool.hatch.build.targets.wheel]
+packages = ["cspdk"]
+
+[tool.hatch.build.targets.wheel.force-include]
+"cspdk--sample-projects" = "cspdk--sample-projects"
+
 [tool.mypy]
 python_version = "3.10"
 strict = true