diff --git a/CMakeLists (conflicted copy 2025-02-24 222236).txt b/CMakeLists (conflicted copy 2025-02-24 222236).txt
new file mode 100644
index 0000000..b01aaf5
--- /dev/null
+++ b/CMakeLists (conflicted copy 2025-02-24 222236).txt	
@@ -0,0 +1,204 @@
+cmake_minimum_required(VERSION 3.20)
+include(cmake/color.cmake)
+set(BLT_VERSION 4.0.27)
+
+set(BLT_TARGET BLT)
+
+project(BLT VERSION ${BLT_VERSION})
+
+set(CMAKE_CXX_STANDARD 17)
+
+option(ENABLE_ADDRSAN "Enable the address sanitizer" OFF)
+option(ENABLE_UBSAN "Enable the ub sanitizer" OFF)
+option(ENABLE_TSAN "Enable the thread data race sanitizer" OFF)
+
+option(BUILD_STD "Build the BLT standard utilities." ON)
+option(BUILD_PROFILING "Build the BLT profiler extension" ON)
+option(BUILD_FS "Build the BLT FS utilities including the NBT + eNBT extension" ON)
+option(BUILD_PARSE "Build the BLT parsers" ON)
+option(BUILD_FORMAT "Build the BLT formatters" ON)
+
+option(BUILD_TESTS "Build the BLT test set" OFF)
+
+option(BLT_DISABLE_STATS "Disable tracking stats in certain objects. Enabling this will cause stat functions to return 0" OFF)
+option(BLT_DISABLE_LOGGING "Disable blt::logging (all macros and will safely disable logging function!)" OFF)
+option(BLT_DISABLE_TRACE "Disable blt::logging BLT_TRACE macro" OFF)
+option(BLT_DISABLE_DEBUG "Disable blt::logging BLT_DEBUG macro" OFF)
+option(BLT_DISABLE_INFO "Disable blt::logging BLT_INFO macro" OFF)
+option(BLT_DISABLE_WARN "Disable blt::logging BLT_WARN macro" OFF)
+option(BLT_DISABLE_ERROR "Disable blt::logging BLT_ERROR macro" OFF)
+option(BLT_DISABLE_FATAL "Disable blt::logging BLT_FATAL macro" OFF)
+
+if(${BLT_DISABLE_STATS})
+    add_compile_definitions(BLT_DISABLE_STATS)
+endif ()
+
+find_program(MOLD "mold")
+
+configure_file(include/blt/config.h.in config/blt/config.h @ONLY)
+
+message("Enabling library compilation")
+if (${BUILD_STD} OR ${BUILD_PROFILING})
+    message(STATUS "Building ${Yellow}standard${ColourReset} cxx files")
+    file(GLOB_RECURSE STD_FILES "${CMAKE_CURRENT_SOURCE_DIR}/src/blt/std/*.cpp")
+else ()
+    set(STD_FILES "")
+endif ()
+
+if (${BUILD_PROFILING})
+    message(STATUS "Building ${Yellow}profiling${ColourReset} cxx files")
+    file(GLOB_RECURSE PROFILING_FILES "${CMAKE_CURRENT_SOURCE_DIR}/src/blt/profiling/*.cpp")
+else ()
+    set(PROFILING_FILES "")
+endif ()
+
+if (${BUILD_FS})
+    message(STATUS "Building ${Yellow}filesystem${ColourReset} cxx files")
+    file(GLOB_RECURSE FS_FILES "${CMAKE_CURRENT_SOURCE_DIR}/src/blt/fs/*.cpp")
+else ()
+    set(FS_FILES "")
+endif ()
+
+if (${BUILD_PARSE})
+    message(STATUS "Building ${Yellow}parser${ColourReset} cxx files")
+    file(GLOB_RECURSE PARSE_FILES "${CMAKE_CURRENT_SOURCE_DIR}/src/blt/parse/*.cpp")
+else ()
+    set(PARSE_FILES "")
+endif ()
+
+if (${BUILD_FORMAT})
+    message(STATUS "Building ${Yellow}format${ColourReset} cxx files")
+    file(GLOB_RECURSE FORMAT_FILES "${CMAKE_CURRENT_SOURCE_DIR}/src/blt/format/*.cpp")
+else ()
+    set(FORMAT_FILES ""
+            include/blt/std/iterator.h)
+endif ()
+
+if (EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/libraries/parallel-hashmap)
+    message("Found Parallel Hashmaps library, using ${Yellow}phmap${ColourReset} over ${Red}std::unordered_map${ColourReset}")
+    include_directories(${CMAKE_CURRENT_SOURCE_DIR}/libraries/parallel-hashmap)
+else()
+    message("Parallel Hashmaps library not found! using ${Yellow}std::unordered_map${ColourReset}")
+endif ()
+
+#include zlib if the user has it.
+find_package(ZLIB QUIET)
+
+if (${ZLIB_FOUND})
+    include_directories(${ZLIB_INCLUDE_DIRS})
+else ()
+    message("ZLIB was not found, this is fine however if you wish you use gzip with NBT it is required.")
+endif ()
+
+include_directories(include/)
+include_directories(${CMAKE_CURRENT_BINARY_DIR}/config/)
+
+add_library(${BLT_TARGET} ${STD_FILES} ${PROFILING_FILES} ${FS_FILES} ${PARSE_FILES} ${FORMAT_FILES})
+
+string(REPLACE "+" "\\+" escaped_source ${CMAKE_CURRENT_SOURCE_DIR})
+string(APPEND escaped_source "/src/blt/.*/")
+list(TRANSFORM STD_FILES REPLACE ${escaped_source} "")
+list(TRANSFORM PROFILING_FILES REPLACE ${escaped_source} "")
+list(TRANSFORM FS_FILES REPLACE ${escaped_source} "")
+list(TRANSFORM PARSE_FILES REPLACE ${escaped_source} "")
+message("Standard Files ${Magenta}${STD_FILES}${ColourReset}")
+message("Profiler Files ${Magenta}${PROFILING_FILES}${ColourReset}")
+message("FS Files ${Magenta}${FS_FILES}${ColourReset}")
+message("Parser Files ${Magenta}${PARSE_FILES}${ColourReset}")
+message("Source: ${CMAKE_SOURCE_DIR}")
+message("Current Source: ${CMAKE_CURRENT_SOURCE_DIR}")
+message("Binary: ${CMAKE_BINARY_DIR}")
+message("Current Binary: ${CMAKE_CURRENT_BINARY_DIR}")
+
+if (${ZLIB_FOUND})
+    target_link_libraries(${BLT_TARGET} PUBLIC ZLIB::ZLIB)
+endif ()
+
+include(cmake/warnings.cmake)
+
+target_include_directories(${BLT_TARGET} PUBLIC include/)
+target_include_directories(${BLT_TARGET} PUBLIC ${CMAKE_CURRENT_BINARY_DIR}/config/)
+if (EXISTS ${CMAKE_CURRENT_SOURCE_DIR}/libraries/parallel-hashmap)
+    message("Including Parallel Hashmap directory")
+    target_include_directories(${BLT_TARGET} PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/libraries/parallel-hashmap)
+endif ()
+
+message("BLT ${Yellow}${BLT_VERSION}${ColourReset} Successfully included!")
+
+message("Installing to ${CMAKE_INSTALL_LIBDIR} with headers at ${CMAKE_INSTALL_INCLUDEDIR}")
+
+file(GLOB_RECURSE BLT_HEADER_FILES "${CMAKE_CURRENT_SOURCE_DIR}/include/*.h")
+foreach (S ${BLT_HEADER_FILES})
+    string(REPLACE "${CMAKE_CURRENT_SOURCE_DIR}/include/" "" SO ${S})
+    string(REGEX REPLACE "\/[A-Z|a-z|0-9|_|-]*\\.h" "/" SA ${SO})
+    list(APPEND BLT_F_HEADERS ${SA})
+    install(FILES ${S} DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/${SA})
+endforeach ()
+
+install(FILES ${CMAKE_BINARY_DIR}/config/blt/config.h DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/blt/)
+
+set_target_properties(${BLT_TARGET} PROPERTIES VERSION ${BLT_VERSION})
+set_target_properties(${BLT_TARGET} PROPERTIES SOVERSION ${PROJECT_VERSION_MAJOR})
+if (NOT ${MOLD} STREQUAL MOLD-NOTFOUND)
+    target_link_options(${BLT_TARGET} PUBLIC -fuse-ld=mold)
+endif ()
+
+install(TARGETS ${BLT_TARGET}
+        CONFIGURATIONS RelWithDebInfo
+        LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
+        PUBLIC_HEADER DESTINATION ${CMAKE_INSTALL_INCLUDEDIR})
+
+macro(blt_add_test name source type)
+
+    message("Adding project ${name} of type ${type}" DEBUG)
+    project(${name}-${type})
+
+    add_executable(${name}-${type} ${source})
+
+    if (NOT ${MOLD} STREQUAL MOLD-NOTFOUND)
+        add_link_options(-fuse-ld=mold)
+    endif ()
+
+    target_link_libraries(${name}-${type} PRIVATE BLT)
+
+    target_compile_options(${name}-${type} PRIVATE -Wall -Wextra -Wpedantic -Wno-comment)
+    target_link_options(${name}-${type} PRIVATE -Wall -Wextra -Wpedantic -Wno-comment)
+    target_compile_definitions(${name}-${type} PRIVATE BLT_DEBUG_LEVEL=${DEBUG_LEVEL})
+
+    if (${TRACK_ALLOCATIONS})
+        target_compile_definitions(${name}-${type} PRIVATE BLT_TRACK_ALLOCATIONS=1)
+    endif ()
+
+    if (${ENABLE_ADDRSAN} MATCHES ON)
+        target_compile_options(${name}-${type} PRIVATE -fsanitize=address)
+        target_link_options(${name}-${type} PRIVATE -fsanitize=address)
+    endif ()
+
+    if (${ENABLE_UBSAN} MATCHES ON)
+        target_compile_options(${name}-${type} PRIVATE -fsanitize=undefined)
+        target_link_options(${name}-${type} PRIVATE -fsanitize=undefined)
+    endif ()
+
+    if (${ENABLE_TSAN} MATCHES ON)
+        target_compile_options(${name}-${type} PRIVATE -fsanitize=thread)
+        target_link_options(${name}-${type} PRIVATE -fsanitize=thread)
+    endif ()
+
+    add_test(NAME ${name} COMMAND ${name}-${type})
+
+    set(failRegex "\\[WARN\\]" "FAIL" "ERROR" "FATAL" "exception")
+    set_property(TEST ${name} PROPERTY FAIL_REGULAR_EXPRESSION "${failRegex}")
+
+    project(${BLT_TARGET})
+endmacro()
+
+if (${BUILD_TESTS})
+    message("Building tests for version ${BLT_VERSION}")
+
+    blt_add_test(blt_iterator tests/iterator_tests.cpp test)
+    blt_add_test(blt_argparse tests/argparse_tests.cpp test)
+
+    message("Built tests")
+endif ()
+
+project(BLT)
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 614e651..5d6aa06 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,6 +1,6 @@
 cmake_minimum_required(VERSION 3.20)
 include(cmake/color.cmake)
-set(BLT_VERSION 4.0.29)
+set(BLT_VERSION 4.0.30)
 
 set(BLT_TARGET BLT)
 
diff --git a/include/blt/parse/argparse_v2.h b/include/blt/parse/argparse_v2.h
index d7dc348..6462789 100644
--- a/include/blt/parse/argparse_v2.h
+++ b/include/blt/parse/argparse_v2.h
@@ -459,7 +459,7 @@ namespace blt::argparse
             return *this;
         }
 
-        argument_builder_t& set_flag()
+        argument_builder_t& make_flag()
         {
             return set_action(action_t::STORE_TRUE);
         }
@@ -614,7 +614,7 @@ namespace blt::argparse
             return b;
         }
 
-        argument_subparser_t& add_subparser(std::string_view dest);
+        argument_subparser_t* add_subparser(std::string_view dest);
 
         argument_parser_t& with_help()
         {
@@ -754,7 +754,7 @@ namespace blt::argparse
         }
 
         template <typename... Aliases>
-        argument_parser_t& add_parser(const std::string_view name, Aliases... aliases)
+        argument_parser_t* add_parser(const std::string_view name, Aliases... aliases)
         {
             static_assert(
                 std::conjunction_v<std::disjunction<std::is_convertible<Aliases, std::string_view>, std::is_constructible<
@@ -762,7 +762,7 @@ namespace blt::argparse
                 "Arguments must be of type string_view, convertible to string_view or be string_view constructable");
             m_parsers.emplace(name, argument_parser_t{});
             ((m_aliases[std::string_view{aliases}] = &m_parsers[name]), ...);
-            return m_parsers[name];
+            return &m_parsers[name];
         }
 
 
diff --git a/src/blt/parse/argparse_v2.cpp b/src/blt/parse/argparse_v2.cpp
index d8f298c..3a2378b 100644
--- a/src/blt/parse/argparse_v2.cpp
+++ b/src/blt/parse/argparse_v2.cpp
@@ -200,7 +200,7 @@ namespace blt::argparse
         {
             return iterate(buffer).skip(start_index).take(compute_take()).map([this](std::string& x)
             {
-                return aligned_internal_string_t{x, max_line_size, buffer[start_index].size()};
+                return aligned_internal_string_t{x, max_line_size, x.size()};
             });
         }
 
@@ -208,7 +208,7 @@ namespace blt::argparse
         {
             return iterate(buffer).skip(start_index).take(compute_take()).map([this](std::string& x)
             {
-                return aligned_internal_string_t{x, max_line_size, buffer[start_index].size()};
+                return aligned_internal_string_t{x, max_line_size, x.size()};
             });
         }
 
@@ -336,10 +336,10 @@ namespace blt::argparse
         return *this;
     }
 
-    argument_subparser_t& argument_parser_t::add_subparser(const std::string_view dest)
+    argument_subparser_t* argument_parser_t::add_subparser(const std::string_view dest)
     {
         m_subparsers.emplace_back(dest, argument_subparser_t{*this});
-        return m_subparsers.back().second;
+        return &m_subparsers.back().second;
     }
 
     argument_storage_t argument_parser_t::parse(argument_consumer_t& consumer)
@@ -395,6 +395,14 @@ namespace blt::argparse
     {
         print_usage();
         aligned_printer_t help{""};
+
+        if (!m_subparsers.empty())
+        {
+            help += "Subcommands:";
+            help.newline();
+            
+        }
+
         if (!m_flag_arguments.empty())
         {
             help += "Options:";
@@ -1365,26 +1373,62 @@ namespace blt::argparse
             std::cout << "Success: run_combined_flag_test\n";
         }
 
+        void run_choice_test()
+        {
+            std::cout << "[Running Test: run_choice_test]\n";
+            argument_parser_t parser;
+
+            parser.add_flag("--hello").set_choices("silly", "crazy", "soft");
+            parser.add_positional("iam").set_choices("different", "choices", "for", "me");
+
+            const auto a1 = make_arguments("--hello", "crazy", "different");
+            const auto r1 = parser.parse(a1);
+            BLT_ASSERT(r1.get("--hello") == "crazy" && "Flag '--hello' should store 'crazy'");
+            BLT_ASSERT(r1.get("iam") == "different" && "Positional 'iam' should store 'different'");
+
+            const auto a2 = make_arguments("--hello", "not_an_option", "different");
+            try
+            {
+                parser.parse(a2);
+                BLT_ASSERT(false && "Parsing should fail due to invalid flag '--hello'");
+            }
+            catch (...)
+            {
+            }
+
+            const auto a3 = make_arguments("--hello", "crazy", "not_a_choice");
+            try
+            {
+                parser.parse(a3);
+                BLT_ASSERT(false && "Parsing should fail due to invalid positional 'iam'");
+            }
+            catch (...)
+            {
+            }
+
+            std::cout << "Success: run_choice_test\n";
+        }
+
         void run_subparser_test()
         {
             std::cout << "[Running Test: run_subparser_test]\n";
             argument_parser_t parser;
 
-            parser.add_flag("--open").set_flag();
+            parser.add_flag("--open").make_flag();
 
-            auto& subparser = parser.add_subparser("mode");
+            const auto subparser = parser.add_subparser("mode");
 
-            auto& n1 = subparser.add_parser("n1");
-            n1.add_flag("--silly").set_flag();
-            n1.add_positional("path");
+            const auto n1 = subparser->add_parser("n1");
+            n1->add_flag("--silly").make_flag();
+            n1->add_positional("path");
 
-            auto& n2 = subparser.add_parser("n2");
-            n2.add_flag("--crazy").set_flag();
-            n2.add_positional("path");
-            n2.add_positional("output");
+            const auto n2 = subparser->add_parser("n2");
+            n2->add_flag("--crazy").make_flag();
+            n2->add_positional("path");
+            n2->add_positional("output");
 
-            auto& n3 = subparser.add_parser("n3");
-            n3.add_flag("--deep").set_flag();
+            const auto n3 = subparser->add_parser("n3");
+            n3->add_flag("--deep").make_flag();
 
             const auto a1 = make_arguments("n1", "--silly");
             try
@@ -1423,8 +1467,6 @@ namespace blt::argparse
             {
             }
 
-            std::cout << std::endl;
-
             const auto a5 = make_arguments("--open", "n2", "path_n2", "output_n2");
             const auto r5 = parser.parse(a5);
             BLT_ASSERT(r5.get<bool>("--open") == true && "Flag '--open' should store true");
@@ -1458,6 +1500,7 @@ namespace blt::argparse
             test_combination_of_valid_and_invalid_flags();
             test_flags_with_different_actions();
             run_combined_flag_test();
+            run_choice_test();
             run_subparser_test();
         }