diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 5ddf04f..6c08f28 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -5,8 +5,6 @@ on:
     branches:
     - main
   pull_request:
-    branches:
-    - main
 
 defaults:
   run:
diff --git a/pyproject.toml b/pyproject.toml
index 9f5713d..ebbbea4 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [build-system]
-build-backend = "setuptools.build_meta"
-requires = ["setuptools"]
+build-backend = "flit_core.buildapi"
+requires = ["flit_core>=3.2"]
 
 [project]
 name = "matplotlib-inline"
diff --git a/setup.py b/setup.py
deleted file mode 100644
index b6c6681..0000000
--- a/setup.py
+++ /dev/null
@@ -1,2 +0,0 @@
-# setup.py shim for use with applications that require it.
-__import__("setuptools").setup()