avro-record-fields-wire-order

Status: IN

Record fields are encoded and decoded in declaration order of the writer schema with no field names on the wire; reordering fields in the schema definition changes the binary format and breaks existing data.

Source: entries/2026/05/29/avro-serializer-avro_serializer.md

Example

for field in schema.fields:
    write_datum(buf, field["type"], record[field["name"]])
# fields written in declaration order, no field tags

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