diff --git a/e2e.sh b/e2e.sh
new file mode 100755
index 0000000..24c7cca
--- /dev/null
+++ b/e2e.sh
@@ -0,0 +1,52 @@
+#!/bin/bash
+
+BASE_URL="http://localhost:8080/api"
+
+echo "=== E2E Pseudo Test ==="
+echo ""
+
+echo "POST /api/orderupdate - Place SELL order"
+curl -s -X POST "$BASE_URL/orderupdate" \
+  -H "Content-Type: application/json" \
+  -d '{
+    "delivery_start_time": "2024-01-15T10:00:00",
+    "delivery_end_time": "2024-01-15T10:15:00",
+    "order_side": "SELL",
+    "quantity": 10,
+    "price": 50.00
+  }' | jq .
+echo ""
+
+echo "POST /api/orderupdate - Place matching BUY order"
+curl -s -X POST "$BASE_URL/orderupdate" \
+  -H "Content-Type: application/json" \
+  -d '{
+    "delivery_start_time": "2024-01-15T10:00:00",
+    "delivery_end_time": "2024-01-15T10:15:00",
+    "order_side": "BUY",
+    "quantity": 5,
+    "price": 50.00
+  }' | jq .
+echo ""
+
+echo "POST /api/orderupdate - Place another SELL order"
+curl -s -X POST "$BASE_URL/orderupdate" \
+  -H "Content-Type: application/json" \
+  -d '{
+    "delivery_start_time": "2024-01-15T10:15:00",
+    "delivery_end_time": "2024-01-15T10:30:00",
+    "order_side": "SELL",
+    "quantity": 20,
+    "price": 45.00
+  }' | jq .
+echo ""
+
+echo "GET /api/market/overview - Get market overview"
+curl -s -X GET "$BASE_URL/market/overview" | jq .
+echo ""
+
+echo "GET /api/purchases/average - Get average purchase price"
+curl -s -X GET "$BASE_URL/purchases/average" | jq .
+echo ""
+
+echo "=== Done ==="
diff --git a/src/main/kotlin/com/frankenergie/smartasset/service/OrderBookService.kt b/src/main/kotlin/com/frankenergie/smartasset/service/OrderBookService.kt
index 6165c80..9ccf808 100644
--- a/src/main/kotlin/com/frankenergie/smartasset/service/OrderBookService.kt
+++ b/src/main/kotlin/com/frankenergie/smartasset/service/OrderBookService.kt
@@ -2,16 +2,21 @@ package com.frankenergie.smartasset.service
 
 import com.frankenergie.smartasset.domain.OrderBook
 import com.frankenergie.smartasset.model.DeliveryPeriod
+import com.frankenergie.smartasset.model.ExecutedPurchase
 import com.frankenergie.smartasset.model.MarketOverviewResponse
+import com.frankenergie.smartasset.model.OrderSide
 import com.frankenergie.smartasset.model.OrderUpdateRequest
 import com.frankenergie.smartasset.model.OrderUpdateResponse
 import com.frankenergie.smartasset.model.QuarterOverview
 import org.springframework.stereotype.Service
+import java.math.BigDecimal
 import java.time.Instant
 import java.util.UUID
 
 @Service
-class OrderBookService {
+class OrderBookService(
+    private val purchaseTrackerService: PurchaseTrackerService
+) {
 
     private val orderBook = OrderBook()
 
@@ -21,13 +26,23 @@ class OrderBookService {
         val period = DeliveryPeriod(request.deliveryStartTime, request.deliveryEndTime)
         val matchedQuantity = orderBook.processOrder(period, request.orderSide, request.quantity, request.price)
 
-        val status = when {
-            matchedQuantity == request.quantity -> "FILLED"
-            matchedQuantity > java.math.BigDecimal.ZERO -> "PARTIALLY_FILLED"
-            else -> "ACCEPTED"
+        if (matchedQuantity > BigDecimal.ZERO && request.orderSide == OrderSide.BUY) {
+            purchaseTrackerService.recordPurchase(
+                ExecutedPurchase(
+                    groupId = "default",
+                    deliveryStart = request.deliveryStartTime,
+                    deliveryEnd = request.deliveryEndTime,
+                    quantity = matchedQuantity,
+                    pricePerMWh = request.price
+                )
+            )
         }
 
-        // TODO: write this to a file
+        val status = when {
+            matchedQuantity == request.quantity -> "FILLED"
+            matchedQuantity > BigDecimal.ZERO -> "PARTIALLY_FILLED"
+            else -> "ACCEPTED"
+        }
 
         return OrderUpdateResponse(orderId = orderId, status = status, timestamp = Instant.now())
     }
diff --git a/src/test/kotlin/com/frankenergie/smartasset/service/OrderBookServiceTest.kt b/src/test/kotlin/com/frankenergie/smartasset/service/OrderBookServiceTest.kt
index 558f0a8..1f6a885 100644
--- a/src/test/kotlin/com/frankenergie/smartasset/service/OrderBookServiceTest.kt
+++ b/src/test/kotlin/com/frankenergie/smartasset/service/OrderBookServiceTest.kt
@@ -11,10 +11,12 @@ import java.time.LocalDateTime
 class OrderBookServiceTest {
 
     private lateinit var service: OrderBookService
+    private lateinit var purchaseTrackerService: PurchaseTrackerService
 
     @BeforeEach
     fun setUp() {
-        service = OrderBookService()
+        purchaseTrackerService = PurchaseTrackerService()
+        service = OrderBookService(purchaseTrackerService)
     }
 
     @Test