diff --git a/.github/workflows/regress.yml b/.github/workflows/regress.yml
index 72a821344..ded64b7f9 100644
--- a/.github/workflows/regress.yml
+++ b/.github/workflows/regress.yml
@@ -70,6 +70,12 @@ jobs:
             utf8proc \
             pkg-config
 
+      - name: increase pty limit
+        if: runner.os == 'macOS'
+        run: |
+          sysctl kern.tty.ptmx_max
+          sudo sysctl -w kern.tty.ptmx_max=999
+
       - name: build
         run: |
           sh autogen.sh