We don’t use the serialization or archiving facilities of multi_index. So globally disable support, which gives a minor improvement in build time, i.e less preprocessing work, given we don’t link any Boost libs.
See: https://www.boost.org/doc/libs/1_78_0/libs/multi_index/doc/tutorial/creation.html
Serialization capabilities are automatically provided by just linking with the appropriate Boost.Serialization library module: it is not necessary to explicitly include any header from Boost.Serialization, apart from those declaring the type of archive used in the process. If not used, however, serialization support can be disabled by globally defining the macro BOOST_MULTI_INDEX_DISABLE_SERIALIZATION. Disabling serialization for Boost.MultiIndex can yield a small improvement in build times, and may be necessary in those defective compilers that fail to correctly process Boost.Serialization headers.
