diff --git a/Library/Homebrew/env_config.rbi b/Library/Homebrew/env_config.rbi
index e36f4ee557..3f664cd315 100644
--- a/Library/Homebrew/env_config.rbi
+++ b/Library/Homebrew/env_config.rbi
@@ -1,10 +1,10 @@
 # typed: strict
 
 module Homebrew::EnvConfig
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.additional_google_analytics_id; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.all_proxy; end
 
   sig { returns(Integer) }
@@ -16,10 +16,10 @@ module Homebrew::EnvConfig
   sig { returns(String) }
   def self.arch; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.artifact_domain; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.auto_update_secs; end
 
   sig { returns(T::Boolean) }
@@ -28,10 +28,10 @@ module Homebrew::EnvConfig
   sig { returns(T::Boolean) }
   def self.bat?; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.bat_config_path; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.bat_theme; end
 
   sig { returns(T::Boolean) }
@@ -82,16 +82,16 @@ module Homebrew::EnvConfig
   sig { returns(T::Boolean) }
   def self.disable_load_formula?; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.display; end
 
   sig { returns(T::Boolean) }
   def self.display_install_times?; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.docker_registry_basic_auth_token; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.docker_registry_token; end
 
   sig { returns(T.nilable(String)) }
@@ -103,7 +103,7 @@ module Homebrew::EnvConfig
   sig { returns(Integer) }
   def self.fail_log_lines; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.forbidden_licenses; end
 
   sig { returns(T::Boolean) }
@@ -118,13 +118,13 @@ module Homebrew::EnvConfig
   sig { returns(T::Boolean) }
   def self.force_vendor_ruby?; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.ftp_proxy; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.git_email; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.git_name; end
 
   sig { returns(String) }
@@ -133,16 +133,16 @@ module Homebrew::EnvConfig
   sig { returns(T.nilable(String)) }
   def self.github_api_token; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.github_packages_token; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.github_packages_user; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.http_proxy; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.https_proxy; end
 
   sig { returns(String) }
@@ -163,7 +163,7 @@ module Homebrew::EnvConfig
   sig { returns(T::Boolean) }
   def self.no_bootsnap?; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.no_cleanup_formulae; end
 
   sig { returns(T::Boolean) }
@@ -199,10 +199,10 @@ module Homebrew::EnvConfig
   sig { returns(T::Boolean) }
   def self.no_installed_dependents_check?; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.no_proxy; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.pip_index_url; end
 
   sig { returns(T::Boolean) }
@@ -217,13 +217,13 @@ module Homebrew::EnvConfig
   sig { returns(T::Boolean) }
   def self.sorbet_runtime?; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.ssh_config_path; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.sudo_askpass; end
 
-  sig { returns(String) }
+  sig { returns(T.nilable(String)) }
   def self.svn; end
 
   sig { returns(String) }
diff --git a/Library/Homebrew/resource.rb b/Library/Homebrew/resource.rb
index 5639184d8f..19aae96525 100644
--- a/Library/Homebrew/resource.rb
+++ b/Library/Homebrew/resource.rb
@@ -296,7 +296,7 @@ class Resource
 
     # PyPI packages: PEP 503 – Simple Repository API <https://peps.python.org/pep-0503>
     if Homebrew::EnvConfig.pip_index_url.present?
-      pip_index_base_url = Homebrew::EnvConfig.pip_index_url.chomp("/").chomp("/simple")
+      pip_index_base_url = T.must(Homebrew::EnvConfig.pip_index_url).chomp("/").chomp("/simple")
       %w[https://files.pythonhosted.org https://pypi.org].each do |base_url|
         extra_urls << url.sub(base_url, pip_index_base_url) if url.start_with?("#{base_url}/packages")
       end
diff --git a/Library/Homebrew/sorbet/custom_generators/env_config.rb b/Library/Homebrew/sorbet/custom_generators/env_config.rb
index 2250e72c5f..e7f372f37a 100644
--- a/Library/Homebrew/sorbet/custom_generators/env_config.rb
+++ b/Library/Homebrew/sorbet/custom_generators/env_config.rb
@@ -4,10 +4,6 @@
 require_relative "../../global"
 require_relative "../../env_config"
 
-def nilable?(method)
-  %w[browser editor github_api_token].include?(method)
-end
-
 File.open("#{__dir__}/../../env_config.rbi", "w") do |file|
   file.write(<<~RUBY)
     # typed: strict