diff --git a/pyproject.toml b/pyproject.toml
index 02ca4e9..4f5652a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -68,12 +68,19 @@ lint = { chain = ["ruff format .", "ruff --fix ."] }
 line-length = 120
 
 [tool.ruff]
+src = ["src"] # see https://docs.astral.sh/ruff/settings/#src
+select = [
+  "I", # isort
+]
 ignore = [
     "F722", # forward-annotation-syntax-error, because of Jaxtyping
     "E731", # do-not-assign-lambda
 ]
 line-length = 120
 
+[tool.ruff.lint.isort]
+combine-as-imports = true
+
 [tool.docformatter]
 black = true