diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 3db4bac79..bb3025379 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -35,8 +35,18 @@ jobs:
             cpu: amd64
           - os: windows
             cpu: amd64
-        branch: [~]
+        branch: [~, upstream/version-2-0]
+        exclude:
+          - target:
+              os: macos
+            branch: upstream/version-2-0
+          - target:
+              os: windows
+            branch: upstream/version-2-0
         include:
+          - branch: upstream/version-2-0
+            branch-short: version-2-0
+            nimflags-extra: --mm:refc
           - target:
               os: linux
             builder: ['self-hosted','ubuntu-22.04']