diff --git a/.github/workflows/activerecord.yml b/.github/workflows/activerecord.yml
index 2b3d2aee..cbc79b20 100644
--- a/.github/workflows/activerecord.yml
+++ b/.github/workflows/activerecord.yml
@@ -1,5 +1,5 @@
 name: activerecord
-on: [push]
+on: [push, pull_request]
 jobs:
   ubuntu:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/mongoid.yml b/.github/workflows/mongoid.yml
index 175b89cb..4ff61be1 100644
--- a/.github/workflows/mongoid.yml
+++ b/.github/workflows/mongoid.yml
@@ -1,5 +1,5 @@
 name: mongoid
-on: [push]
+on: [push, pull_request]
 jobs:
   ubuntu:
     runs-on: ubuntu-latest
diff --git a/Appraisals b/Appraisals
index 5bb901ee..e63ec426 100644
--- a/Appraisals
+++ b/Appraisals
@@ -1,5 +1,6 @@
 appraise 'mongoid-5' do
   gem "mongoid", "~> 5"
+  gem "mongo", "< 2.17"
   gem "bson_ext", "1.5.1"
   gem 'bigdecimal', '1.4.2'
 end
diff --git a/gemfiles/mongoid_5.gemfile b/gemfiles/mongoid_5.gemfile
index 7380608e..369038e9 100644
--- a/gemfiles/mongoid_5.gemfile
+++ b/gemfiles/mongoid_5.gemfile
@@ -3,6 +3,7 @@
 source "https://rubygems.org"
 
 gem "mongoid", "~> 5"
+gem "mongo", "< 2.17"
 gem "bson_ext", "1.5.1"
 gem "bigdecimal", "1.4.2"