diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 2177a27..19e3392 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -7,9 +7,11 @@ on:
   pull_request:
     branches:
       - master
+      - b_3.x
   push:
     branches:
       - master
+      - b_3.x
     tags:
       - v*