You can define BOOST_TEXT_STRING_INSERT_MAX to be the size in bytes that you want as the limit on the size of unencoded_rope and rope nodes when doing in-place insertions.

Boost.Text will automatically use concepts to constrain templates when building in C++20 mode, if the compiler defines __cpp_lib_concepts. To disable the use of concepts, define BOOST_TEXT_DISABLE_CONCEPTS.

Boost.Text will automatically use coroutines when building in C++20 mode, if the compiler defines __cpp_impl_coroutine and __cpp_lib_coroutine. To disable the use of coroutines, define BOOST_TEXT_DISABLE_COROUTINES.

Boost.Text will automatically use std::filesystem when building in C++17 mode, if the compiler defines __cpp_lib_filesystem. To disable the use of std::filesystem (and use boost::fileystem instead), define disable_std_fs_m.