diff --git a/prometheus_aggregator.gemspec b/prometheus_aggregator.gemspec
index 725324e..0c2af5f 100644
--- a/prometheus_aggregator.gemspec
+++ b/prometheus_aggregator.gemspec
@@ -25,7 +25,7 @@ Gem::Specification.new do |spec|
   spec.add_runtime_dependency "net_tcp_client", "~> 2.0"
 
   spec.add_development_dependency "excon", "~> 0.62"
-  spec.add_development_dependency "faraday", "~> 0.15"
+  spec.add_development_dependency "faraday", "~> 1.4"
   spec.add_development_dependency "minitest", "~> 5.0"
   spec.add_development_dependency "rack", "~> 2.0"
   spec.add_development_dependency "rake", "~> 12.3"