diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 74a9c7f2..afc481a2 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -25,12 +25,12 @@ jobs:
     runs-on: ubuntu-latest
     continue-on-error: ${{ matrix.allow-failure || false }}
     strategy:
-      fail-fast: true
+      fail-fast: false
       matrix:
         ruby-version:
           - '3.0'
           - '3.1'
-          - 'jruby-9.3.10'
+          - 'jruby-9.3.10' # oldest supported jruby
           - 'jruby'
         include: # HEAD-versions
           - ruby-version: 'head'
diff --git a/Gemfile b/Gemfile
index be173b20..2c02c1ec 100644
--- a/Gemfile
+++ b/Gemfile
@@ -3,3 +3,6 @@
 source "https://rubygems.org"
 
 gemspec
+
+# https://github.com/ruby/psych/issues/655
+gem "psych", "!= 5.1.1", platforms: %i[jruby]