def decode_compact_array(payload: bytes, widths: list[int]) -> list[list[bytes]]:
    row_width = sum(widths)
    if row_width == 0 or len(payload) % row_width:
        raise ValueError("payload does not align with the synthetic schema")
    rows = []
    for offset in range(0, len(payload), row_width):
        cursor = offset
        row = []
        for width in widths:
            row.append(payload[cursor:cursor + width])
            cursor += width
        rows.append(row)
    return rows