diff --git a/ext/extconf.rb b/ext/extconf.rb
index 99207d234..846436d8a 100644
--- a/ext/extconf.rb
+++ b/ext/extconf.rb
@@ -64,6 +64,12 @@ def cook_and_activate
 			self.activate
 			self
 		end
+
+		# Increase number of download retries; otherwise it fails often in CI
+		alias download_file_count_3 download_file
+		def download_file(url, full_path, count = 60)
+			download_file_count_3(url, full_path, count)
+		end
 	end
 
 	openssl_platform = with_config("openssl-platform")
diff --git a/spec/helpers.rb b/spec/helpers.rb
index bba0eeb86..015eccd07 100644
--- a/spec/helpers.rb
+++ b/spec/helpers.rb
@@ -684,7 +684,7 @@ def set_etc_hosts(hostaddr, hostname)
 	config.filter_run_excluding( :scheduler ) if RUBY_VERSION < "3.0" || (RUBY_PLATFORM =~ /mingw|mswin/ && RUBY_VERSION < "3.1") || !Fiber.respond_to?(:scheduler)
 	config.filter_run_excluding( :scheduler_address_resolve ) if RUBY_VERSION < "3.1"
 	config.filter_run_excluding( :ipv6 ) if Addrinfo.getaddrinfo("localhost", nil, nil, :STREAM).size < 2
-	config.filter_run_excluding( :ractor ) unless defined?(Ractor)
+	config.filter_run_excluding( :ractor ) unless defined?(Ractor) && RUBY_VERSION >= "4"
 	begin
 		PG.require_bigdecimal_without_warning
 	rescue LoadError
diff --git a/spec/pg/connection_spec.rb b/spec/pg/connection_spec.rb
index d587721b3..6ed2c5112 100644
--- a/spec/pg/connection_spec.rb
+++ b/spec/pg/connection_spec.rb
@@ -3089,7 +3089,11 @@ def with_std_conf_strings(conn, onoff)
 				https://www.postgresql.org/docs/current/sql-syntax-lexical.html. Should you find any syntax changes in
 				string literals - please adjust PG::Connection::PLACEHOLDER_RE constant accordingly
 			TEXT
-			expect(latest_commit_info.dig(0, :sha)).to eq("45762084545ec14dbbe66ace1d69d7e89f8978ac"), error_message
+			expect(latest_commit_info).to be_kind_of(Array), latest_commit_info.to_s
+			expect(latest_commit_info[0]).to be_kind_of(Hash), latest_commit_info.to_s
+			expect(latest_commit_info[0][:sha]).to eq("45762084545ec14dbbe66ace1d69d7e89f8978ac"), error_message
+		rescue SocketError, JSON::ParserError => err
+			skip "cannot access PostgreSQL git repository: #{err}"
 		end
 
 		describe "default type map" do