diff --git a/CMakeLists.txt b/CMakeLists.txt
index dac6ddd..7e5af9d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -74,8 +74,8 @@ target_link_libraries(${PROJECT} ruc)
 # Execute target
 
 add_custom_target(run
-    COMMAND ${PROJECT})
-add_dependencies(run ${PROJECT})
+    COMMAND ${PROJECT}
+	DEPENDS ${PROJECT})
 
 # ------------------------------------------
 # Test targets
diff --git a/src/settings.cpp b/src/settings.cpp
new file mode 100644
index 0000000..807173c
--- /dev/null
+++ b/src/settings.cpp
@@ -0,0 +1,17 @@
+/*
+ * Copyright (C) 2023 Riyyi
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#include "settings.h"
+
+namespace blaze {
+
+std::string_view Settings::get(std::string_view key) const
+{
+	VERIFY(m_settings.find(key) != m_settings.end(), "setting does not exist");
+	return m_settings.at(key);
+};
+
+} // namespace blaze
diff --git a/src/settings.h b/src/settings.h
new file mode 100644
index 0000000..20d086e
--- /dev/null
+++ b/src/settings.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2023 Riyyi
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#pragma once
+
+#include "ruc/meta/assert.h"
+#include "ruc/singleton.h"
+#include <string>
+#include <string_view>
+#include <unordered_map>
+#include <vector>
+
+namespace blaze {
+
+class Settings final : public ruc::Singleton<Settings> {
+public:
+	Settings(s) {}
+	virtual ~Settings() = default;
+
+	std::string_view get(std::string_view key) const;
+	void set(std::string_view key, std::string_view value) { m_settings[key] = value; };
+
+private:
+	std::unordered_map<std::string_view, std::string_view> m_settings;
+};
+
+} // namespace blaze
diff --git a/src/step1_read_print.cpp b/src/step1_read_print.cpp
index 9544026..e901b2e 100644
--- a/src/step1_read_print.cpp
+++ b/src/step1_read_print.cpp
@@ -4,37 +4,42 @@
 #include <string>   // std::getline
 #include <string_view>
 
-#include "error.h"
+#include "ruc/argparser.h"
 #include "ruc/format/color.h"
 
 #include "ast.h"
+#include "error.h"
 #include "lexer.h"
 #include "printer.h"
 #include "reader.h"
-
-#define PRETTY_PRINT 0
+#include "settings.h"
 
 #if 1
 auto read(std::string_view input) -> blaze::ASTNode*
 {
 	blaze::Lexer lexer(input);
 	lexer.tokenize();
-	// lexer.dump();
+	if (blaze::Settings::the().get("dump-lexer") == "1") {
+		lexer.dump();
+	}
+
 	blaze::Reader reader(std::move(lexer.tokens()));
 	reader.read();
-	// reader.dump();
+	if (blaze::Settings::the().get("dump-reader") == "1") {
+		reader.dump();
+	}
 
 	return reader.node();
 }
 
-auto eval(blaze::ASTNode* node) -> blaze::ASTNode*
+auto eval(blaze::ASTNode* ast) -> blaze::ASTNode*
 {
-	return node;
+	return ast;
 }
 
-auto print(blaze::ASTNode* node) -> void
+auto print(blaze::ASTNode* exp) -> void
 {
-	blaze::Printer printer(node);
+	blaze::Printer printer(exp);
 	printer.dump();
 }
 
@@ -52,25 +57,41 @@ static auto cleanup(int signal) -> void
 	std::exit(signal);
 }
 
-auto main() -> int
+auto main(int argc, char* argv[]) -> int
 {
+	bool dump_lexer = false;
+	bool dump_reader = false;
+	bool pretty_print = false;
+
+	// CLI arguments
+	ruc::ArgParser arg_parser;
+	arg_parser.addOption(dump_lexer, 'l', "dump-lexer", nullptr, nullptr);
+	arg_parser.addOption(dump_reader, 'r', "dump-reader", nullptr, nullptr);
+	arg_parser.addOption(pretty_print, 'c', "color", nullptr, nullptr);
+	arg_parser.parse(argc, argv);
+
+	// Set settings
+	blaze::Settings::the().set("dump-lexer", dump_lexer ? "1" : "0");
+	blaze::Settings::the().set("dump-reader", dump_reader ? "1" : "0");
+	blaze::Settings::the().set("pretty-print", pretty_print ? "1" : "0");
+
 	// Signal callbacks
 	std::signal(SIGINT, cleanup);
 	std::signal(SIGTERM, cleanup);
 
 	while (true) {
-	#if PRETTY_PRINT
-		print(fg(ruc::format::TerminalColor::Blue), "user>");
-		print(" ");
-		print("\033[1m");
-	#else
-		print("user> ");
-	#endif
+		if (!pretty_print) {
+			print("user> ");
+		}
+		else {
+			print(fg(ruc::format::TerminalColor::Blue), "user>");
+			print(" \033[1m");
+		}
 		std::string line;
 		std::getline(std::cin, line);
-	#if PRETTY_PRINT
-		print("\033[0m");
-	#endif
+		if (pretty_print) {
+			print("\033[0m");
+		}
 
 		// Exit with Ctrl-D
 		if (std::cin.eof() || std::cin.fail()) {