diff --git a/bundler.d/ci_gem_pins.rb b/bundler.d/ci_gem_pins.rb
new file mode 100644
index 0000000..56ca542
--- /dev/null
+++ b/bundler.d/ci_gem_pins.rb
@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+# Pin gems that resolve to incompatible versions when bundled from the project
+# root (which has no Gemfile.lock). Remove these once upstream Hyku PRs land:
+#   - blacklight_advanced_search 8.0 adds :facets_for_advanced_search_form to
+#     the default processor chain, breaking adv_search_builder_spec
+#   - json 2.13+ raises TypeError on JSON.load(Hash), breaking account_settings
+#     factory setup in tests
+override_gem 'blacklight_advanced_search', '~> 7.0'
+ensure_gem 'json', '~> 2.12.2'