ATLAX Match Engine

1. 1.Better price executes first.
2. 2.Same price executes by earlier timestamp.
3. 3.Market orders consume available liquidity until filled or slippage limit is hit.
4. 4.Post-only orders cancel if they would immediately take liquidity.
5. 5.Reduce-only orders cannot increase exposure.
6. 6.Liquidation orders receive priority during liquidation events.
7. 7.All fills generate settlement messages and event logs.

for incoming_order in order_queue:
    validate_order(incoming_order)
    while incoming_order.remaining_size > 0:
        best_opposite_order = orderbook.get_best_price()
        if price_crosses(incoming_order, best_opposite_order):
            fill = match(incoming_order, best_opposite_order)
            emit_fill(fill)
            send_to_settlement(fill)
        else:
            rest_order_on_book(incoming_order)
            break