This is necessary to get stuff into the Apple App Store for iOS. Apple does not really like using dynamic libraries in iOS. Also the libcharset thing is apparently a "private" symbol.
See https://github.com/reflex-frp/reflex-platform/pull/307 for more details.
See 3dee596ed1 (diff-261d74054a31954b7c6175e2e7e28356) for discussion