utf-8 / private use area

encoding U+E001 over the wire
01 — sender / encode
sending over the internet
02 — bytes on the wire
— waiting for encode —
sending over the internet
03 — receiver / decode bytes → codepoint
— waiting for bytes —
04 — registry lookup → render glyph
— waiting for codepoint —

U+E001 lives in Unicode's Private Use Area (U+E000–U+F8FF). UTF-8 encodes it faithfully as 3 bytes. The encoding layer is standard.

Anyone receiving [238, 128, 129] without this registry sees nothing. Only this decoder knows what those bytes mean.

Transport is universal. Meaning is private.