diff --git a/changelog.d/9.fixing.md b/changelog.d/9.fixing.md
new file mode 100644
index 0000000..ccc9e5c
--- /dev/null
+++ b/changelog.d/9.fixing.md
@@ -0,0 +1 @@
+Add missing 'attrs' package to project dependencies.
\ No newline at end of file
diff --git a/pyproject.toml b/pyproject.toml
index 7af3707..0509dbb 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -34,6 +34,7 @@ dynamic = [
   "version",
 ]
 dependencies = [
+  "attrs",
   "jinja2>=2.7.2",
   "pluggy",
   "PyYAML",
@@ -94,7 +95,6 @@ python = "3.11"
 
 [tool.hatch.envs.lint]
 dependencies = [
-    "attrs", # needed for type-checking tests
     "black",
     "ruff",
     "mypy",
@@ -122,7 +122,6 @@ lint-action = [
 
 [tool.hatch.envs.ci]
 dependencies = [
-    "attrs",
     "coverage[toml]",
     "pytest",
     "pytest-cov",