diff --git a/fdk.gemspec b/fdk.gemspec
index 29e985e..6094fdd 100644
--- a/fdk.gemspec
+++ b/fdk.gemspec
@@ -13,10 +13,10 @@ Gem::Specification.new do |s|
   s.license     = "Apache-2.0"
   s.required_ruby_version = ">= 2.5"
 
-  s.add_runtime_dependency "json", "~> 2.1", ">= 2.1.0"
-  s.add_runtime_dependency "webrick", "~> 1.4", ">= 1.4.2"
-  s.add_development_dependency "net_http_unix", "~> 0.2", ">= 0.2.1"
-  s.add_development_dependency "rubocop", "~> 0.60"
+  s.add_runtime_dependency "json", "~> 2.5", ">= 2.5.1"
+  s.add_runtime_dependency "webrick", "~> 1.7", ">= 1.7.0"
+  s.add_development_dependency "net_http_unix", "~> 0.2", ">= 0.2.2"
+  s.add_development_dependency "rubocop", "~> 1.21"
 
   s.files = Dir["Rakefile", "{bin,lib,man,test,spec}/**/*", "README*", "LICENSE*"] & `git ls-files -z`.split("\0")
 end
diff --git a/lib/fdk/context.rb b/lib/fdk/context.rb
index da9a032..ea86c10 100644
--- a/lib/fdk/context.rb
+++ b/lib/fdk/context.rb
@@ -82,8 +82,7 @@ class Context
     #   Replace X with the upper cased name of the config variable you set.
     #   e.g. minio_secret=secret will be exposed via MINIO_SECRET env var.
 
-    attr_reader :headers
-    attr_reader :response_headers
+    attr_reader :headers, :response_headers
 
     def initialize(headers_in, headers_out)
       @headers = headers_in
@@ -123,8 +122,7 @@ def http_context
   # Represents the context data (inbound && outbound)
   # for the execution passed as HTTP headers
   class HTTPContext
-    attr_reader :headers
-    attr_reader :response_headers
+    attr_reader :headers, :response_headers
 
     def initialize(ctx)
       fn_http_h_ = "fn-http-h-"
diff --git a/lib/fdk/function.rb b/lib/fdk/function.rb
index de1132d..bfa93b2 100644
--- a/lib/fdk/function.rb
+++ b/lib/fdk/function.rb
@@ -20,6 +20,7 @@ module FDK
   # Function represents a function function or lambda
   class Function
     attr_reader :format, :function
+
     def initialize(function:, format:)
       raise "'#{format}' not supported in Ruby FDK." unless format == "http-stream"
 
diff --git a/lib/fdk/listener.rb b/lib/fdk/listener.rb
index c3c23b2..c87f211 100644
--- a/lib/fdk/listener.rb
+++ b/lib/fdk/listener.rb
@@ -89,7 +89,7 @@ def socket_path
     end
 
     def private_socket_path
-      socket_path + ".private"
+      "#{socket_path}.private"
     end
 
     def log_frame_header(headers)