diff --git a/l4/.gitignore b/l4/.gitignore
new file mode 100644
index 0000000..c2bd88b
--- /dev/null
+++ b/l4/.gitignore
@@ -0,0 +1,3 @@
+*.nef
+config.json
+
diff --git a/l4/data.json b/l4/data.json
new file mode 100644
index 0000000..a8d4f08
--- /dev/null
+++ b/l4/data.json
@@ -0,0 +1,42 @@
+{
+  "store": {
+    "item": [
+      {
+        "id": 0,
+        "category": "Headgear",
+        "title": "Bucket Hat",
+        "price": 400
+      },
+      {
+        "id": 1,
+        "category": "Headgear",
+        "title": "Fugu Bell Hat",
+        "price": 1700
+      },
+      {
+        "id": 2,
+        "category": "Clothing",
+        "title": "Lumberjack Shirt",
+        "price": 800
+      },
+      {
+        "id": 3,
+        "category": "Clothing",
+        "title": "Pink Hoodie",
+        "price": 3400
+      },
+      {
+        "id": 4,
+        "category": "Shoes",
+        "title": "Cyan Trainers",
+        "price": 700
+      },
+      {
+        "id": 5,
+        "category": "Shoes",
+        "title": "Red Hi-Tops",
+        "price": 1800
+      }
+    ]
+  }
+}
\ No newline at end of file
diff --git a/l4/go.mod b/l4/go.mod
new file mode 100644
index 0000000..e25bb2b
--- /dev/null
+++ b/l4/go.mod
@@ -0,0 +1,5 @@
+module oracle
+
+go 1.20
+
+require github.com/nspcc-dev/neo-go/pkg/interop v0.0.0-20231027092558-8ed6d97085d3
diff --git a/l4/go.sum b/l4/go.sum
new file mode 100644
index 0000000..0e8d391
--- /dev/null
+++ b/l4/go.sum
@@ -0,0 +1,2 @@
+github.com/nspcc-dev/neo-go/pkg/interop v0.0.0-20231027092558-8ed6d97085d3 h1:ybQcK5pTNAR+wQU3k4cGeOZN6OCiVcQkbgR3Zl6NFPU=
+github.com/nspcc-dev/neo-go/pkg/interop v0.0.0-20231027092558-8ed6d97085d3/go.mod h1:J/Mk6+nKeKSW4wygkZQFLQ6SkLOSGX5Ga0RuuuktEag=
diff --git a/l4/lottery/config.yml b/l4/lottery/config.yml
new file mode 100644
index 0000000..f7834a0
--- /dev/null
+++ b/l4/lottery/config.yml
@@ -0,0 +1,5 @@
+name: "Lottery"
+supportedstandards: []
+events:
+permissions:
+  - methods: []
diff --git a/l4/lottery/lottery_contract.go b/l4/lottery/lottery_contract.go
new file mode 100644
index 0000000..d975d20
--- /dev/null
+++ b/l4/lottery/lottery_contract.go
@@ -0,0 +1,13 @@
+package lottery
+
+import (
+	"github.com/nspcc-dev/neo-go/pkg/interop/runtime"
+)
+
+func IsWinner(playerName string) bool {
+	if playerName == "demo" {
+		return true
+	}
+	random := runtime.GetRandom()
+	return random < 100
+}
diff --git a/l4/player/config.yml b/l4/player/config.yml
new file mode 100644
index 0000000..121ed86
--- /dev/null
+++ b/l4/player/config.yml
@@ -0,0 +1,5 @@
+name: "Player"
+supportedstandards: []
+events:
+permissions:
+  - methods: ["request", "isWinner"]
diff --git a/l4/player/player_contract.go b/l4/player/player_contract.go
new file mode 100644
index 0000000..461b178
--- /dev/null
+++ b/l4/player/player_contract.go
@@ -0,0 +1,125 @@
+package player
+
+import (
+	"github.com/nspcc-dev/neo-go/pkg/interop/native/oracle"
+	"github.com/nspcc-dev/neo-go/pkg/interop/native/std"
+	"github.com/nspcc-dev/neo-go/pkg/interop/runtime"
+	"github.com/nspcc-dev/neo-go/pkg/interop/storage"
+)
+
+type Player struct {
+	balance int
+	items   []int
+}
+
+const storeURLKey = "storeURL"
+
+func _deploy(data interface{}, isUpdate bool) {
+	if isUpdate {
+		return
+	}
+
+	// TODO: change url to point to the new repository after we merge PR
+	ctx := storage.GetContext()
+	storeURL := "https://git.frostfs.info/vdomnich-yadro/oracle-demo/raw/branch/master/data.json"
+	storage.Put(ctx, storeURLKey, storeURL)
+}
+
+func NewPlayer(playerName string) {
+	ctx := storage.GetContext()
+
+	existingPlayer := storage.Get(ctx, playerName)
+	if existingPlayer != nil {
+		panic("player already exists")
+	}
+
+	items := make([]int, 0)
+
+	// NOTE: the commented code below requires `lottery/lottery_contract.go` to be deployed on the chain
+	// If you would like to uncomment it, please:
+	// 1. Deploy `lottery/lottery_contract.go` contract to your chain
+	// 2. Replace hash inisde `address.ToHash160` with the hash of deployed contract
+	// 3. Add imports to this file:
+	//    "github.com/nspcc-dev/neo-go/pkg/interop/contract"
+	//    "github.com/nspcc-dev/neo-go/pkg/interop/lib/address"
+	// 4. Now you're ready to uncomment the code and run player contract in integration with lottery.
+	//
+	// lotteryHash := address.ToHash160("NVBGxUL69FJEV9nhrZQQhPbhkzzvsJqF8q")
+	// isWinner := contract.Call(lotteryHash, "isWinner", contract.ReadOnly, playerName).(bool)
+	// if isWinner {
+	// 	items = append(items, 0)
+	// }
+
+	player := Player{
+		balance: 3000,
+		items:   items,
+	}
+	storage.Put(ctx, playerName, std.Serialize(player))
+}
+
+func getPlayer(playerName string) Player {
+	ctx := storage.GetReadOnlyContext()
+	data := storage.Get(ctx, playerName)
+	if data == nil {
+		panic("player not found")
+	}
+
+	return std.Deserialize(data.([]byte)).(Player)
+}
+
+func Balance(playerName string) int {
+	p := getPlayer(playerName)
+	return p.balance
+}
+
+func Items(playerName string) []int {
+	p := getPlayer(playerName)
+	return p.items
+}
+
+func BuyItem(playerName string, itemID int) {
+	player := getPlayer(playerName)
+	for i := range player.items {
+		if itemID == player.items[i] {
+			panic("item has already been purchased")
+		}
+	}
+
+	ctx := storage.GetContext()
+	storeURL := storage.Get(ctx, storeURLKey).(string)
+
+	filter := []byte("$.store.item[" + std.Itoa10(itemID) + "]")
+
+	oracle.Request(storeURL, filter, "cbBuyItem", playerName, 2*oracle.MinimumResponseGas)
+}
+
+func CbBuyItem(url string, userData any, code int, result []byte) {
+	callingHash := runtime.GetCallingScriptHash()
+	if !callingHash.Equals(oracle.Hash) {
+		panic("not called from the oracle contract")
+	}
+	if code != oracle.Success {
+		panic("request failed for " + url + " with code " + std.Itoa(code, 10))
+	}
+	runtime.Log("result for " + url + " is: " + string(result))
+
+	// Remove quotes that surround resulting JSON
+	resultLen := len(result)
+	data := std.JSONDeserialize(result[1 : resultLen-1]).(map[string]any)
+
+	price := data["price"].(int)
+	gearID := data["id"].(int)
+
+	playerName := userData.(string)
+	player := getPlayer(playerName)
+
+	if player.balance < price {
+		panic("insufficient balance")
+	}
+
+	player.balance -= price
+	player.items = append(player.items, gearID)
+
+	ctx := storage.GetContext()
+	storage.Put(ctx, playerName, std.Serialize(player))
+}
diff --git a/l4/slides.pdf b/l4/slides.pdf
new file mode 100644
index 0000000..604b685
Binary files /dev/null and b/l4/slides.pdf differ