diff --git a/aegisub/libaegisub/common/option.cpp b/aegisub/libaegisub/common/option.cpp
index 7656813cf..14147c11e 100644
--- a/aegisub/libaegisub/common/option.cpp
+++ b/aegisub/libaegisub/common/option.cpp
@@ -21,8 +21,6 @@
 #include "libaegisub/option.h"
 
 #include <cassert>
-#include <fstream>
-#include <map>
 #include <memory>
 #include <sstream>
 
@@ -69,7 +67,9 @@ namespace {
 namespace agi {
 
 Options::Options(const std::string &file, const std::string& default_config, const OptionSetting setting)
-: config_file(file), setting(setting) {
+: config_file(file)
+, setting(setting)
+{
 	LOG_D("agi/options") << "New Options object";
 	std::istringstream stream(default_config);
 	LoadConfig(stream);
@@ -127,7 +127,7 @@ OptionValue* Options::Get(const std::string &name) {
 	throw OptionErrorNotFound("Option value not found: " + name);
 }
 
-void Options::Flush() {
+void Options::Flush() const {
 	json::Object obj_out;
 
 	for (auto const& ov : values) {
diff --git a/aegisub/libaegisub/include/libaegisub/option.h b/aegisub/libaegisub/include/libaegisub/option.h
index 245cd31b5..f1c486f5d 100644
--- a/aegisub/libaegisub/include/libaegisub/option.h
+++ b/aegisub/libaegisub/include/libaegisub/option.h
@@ -59,12 +59,8 @@ private:
 	/// Internal OptionValueMap
 	OptionValueMap values;
 
-	/// @brief Create option object.
-	/// @param path Path to store
-	::json::Object CreateObject(std::string path);
-
 	/// User config (file that will be written to disk)
-	std::string config_file;
+	const std::string config_file;
 
 	/// Settings.
 	const OptionSetting setting;
@@ -101,7 +97,7 @@ public:
 	void ConfigUser();
 
 	/// Write the user configuration to disk, throws an exception if something goes wrong.
-	void Flush();
+	void Flush() const;
 };
 
 } // namespace agi