diff --git a/.git-blame-ignore-revs b/.git-blame-ignore-revs
new file mode 100644
index 0000000000..535e8aeada
--- /dev/null
+++ b/.git-blame-ignore-revs
@@ -0,0 +1,4 @@
+# START initial autopep8-driven formatting
+commit 6b875871545042ee8414ba05f7743eb9a491f631  # Make nested funcs sparse @ `cheroot.ssl.pyopenssl`
+commit b234de9e9d3ca6a3ba5ad4efe87f2347045c19b4  # Dedent nested tuple items @ `test_conn`
+# END initial autopep8-driven formatting
diff --git a/.gitattributes b/.gitattributes
index c53694a95f..938176b695 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -4,4 +4,7 @@
 # Needed for setuptools-scm-git-archive
 .git_archival.txt  export-subst
 
+# Blame ignore list entries are expected to always be appended, never edited
+.git-blame-ignore-revs  merge=union
+
 CHANGES.rst        merge=union