diff --git a/concourse/loofah.yml b/concourse/loofah.yml
index 9c9cc45..34ba2e8 100644
--- a/concourse/loofah.yml
+++ b/concourse/loofah.yml
@@ -14,7 +14,6 @@ jobs:
 % RUBIES[:mri].each do |ruby_version|
   - name: ruby-<%= ruby_version %>
     public: true
-    serial_groups: ["ruby"]
     plan:
       - get: ci
       - get: loofah
@@ -37,7 +36,6 @@ jobs:
 % RUBIES[:jruby].each do |jruby_version|
   - name: jruby-<%= jruby_version %>
     public: true
-    serial_groups: ["jruby"]
     plan:
       - get: ci
       - get: loofah
diff --git a/concourse/loofah.yml.generated b/concourse/loofah.yml.generated
index 83deb7d..e2a4ac7 100644
--- a/concourse/loofah.yml.generated
+++ b/concourse/loofah.yml.generated
@@ -18,7 +18,6 @@ resources:
 jobs:
   - name: ruby-2.4
     public: true
-    serial_groups: ["ruby"]
     plan:
       - get: ci
       - get: loofah
@@ -38,7 +37,6 @@ jobs:
             path: ci/concourse/tasks/rake-test/run.sh
   - name: ruby-2.5
     public: true
-    serial_groups: ["ruby"]
     plan:
       - get: ci
       - get: loofah
@@ -58,7 +56,6 @@ jobs:
             path: ci/concourse/tasks/rake-test/run.sh
   - name: ruby-2.6
     public: true
-    serial_groups: ["ruby"]
     plan:
       - get: ci
       - get: loofah
@@ -78,7 +75,6 @@ jobs:
             path: ci/concourse/tasks/rake-test/run.sh
   - name: ruby-2.7
     public: true
-    serial_groups: ["ruby"]
     plan:
       - get: ci
       - get: loofah
@@ -99,7 +95,6 @@ jobs:
 
   - name: jruby-9.2
     public: true
-    serial_groups: ["jruby"]
     plan:
       - get: ci
       - get: loofah