diff --git a/docker-compose.yml b/docker-compose.yml
index 09df9d1..579d24d 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -197,6 +197,10 @@ services:
       - SMTP_SECURE=${SMTP_SECURE:-false}
       - SMTP_USER=${SMTP_USER:-}
       - SMTP_PASS=${SMTP_PASS:-}
+      - KAFKA_BROKERS=kafka:29092
+    depends_on:
+      kafka:
+        condition: service_healthy
     networks:
       - auron-network
     restart: unless-stopped
diff --git a/services/notification-service/.env.example b/services/notification-service/.env.example
new file mode 100644
index 0000000..f504d6e
--- /dev/null
+++ b/services/notification-service/.env.example
@@ -0,0 +1,9 @@
+# Notification Service
+PORT=8086
+SMTP_HOST=localhost
+SMTP_PORT=1025
+SMTP_FROM=noreply@auron.shop
+SMTP_USER=
+SMTP_PASS=
+SMTP_SECURE=false
+KAFKA_BROKERS=localhost:9092
diff --git a/services/notification-service/Dockerfile b/services/notification-service/Dockerfile
new file mode 100644
index 0000000..fcadd3d
--- /dev/null
+++ b/services/notification-service/Dockerfile
@@ -0,0 +1,23 @@
+FROM golang:1.25-alpine AS builder
+
+WORKDIR /app
+
+RUN apk add --no-cache git
+
+COPY go.mod go.sum ./
+
+COPY . .
+
+RUN CGO_ENABLED=0 GOOS=linux go build -o /notification-service .
+
+FROM alpine:3.18
+
+RUN apk add --no-cache ca-certificates curl
+
+WORKDIR /app
+
+COPY --from=builder /notification-service .
+
+EXPOSE 8086
+
+CMD ["./notification-service"]
diff --git a/services/notification-service/IMPLEMENTATION_PLAN.md b/services/notification-service/IMPLEMENTATION_PLAN.md
new file mode 100644
index 0000000..86f6b5c
--- /dev/null
+++ b/services/notification-service/IMPLEMENTATION_PLAN.md
@@ -0,0 +1,317 @@
+# Notification Service — Implementation Plan
+
+## Overview
+
+The notification-service delivers transactional emails to users triggered by domain events
+published on Kafka by other services. It consumes events, fetches any additional context it
+needs, renders email content, and sends via SMTP (using Go's `net/smtp` standard library).
+
+No database is required — all state comes from incoming events.  
+No REST API endpoints — the service is entirely event-driven.  
+The `/health` endpoint (required by docker-compose healthcheck) is the only HTTP surface.
+
+**Port:** `8086`  
+**Kafka consumer group:** `notification-service`
+
+---
+
+## Topics consumed and emails sent
+
+| Kafka Topic          | Email sent                                       |
+|----------------------|--------------------------------------------------|
+| `user.created`       | Welcome email to new user                        |
+| `order.created`      | Order confirmation with item summary             |
+| `order.cancelled`    | Order cancellation notice                        |
+| `payment.completed`  | Payment receipt / success confirmation           |
+| `payment.failed`     | Payment failure notice with reason               |
+| `inventory.low_stock`| (internal) low-stock alert — no user email       |
+
+> `inventory.low_stock` is consumed but emails are suppressed for now (logged only).
+> `payment.created` is skipped — that event carries Stripe client_secret; not relevant here.
+
+---
+
+## Directory structure
+
+```
+services/notification-service/
+├── IMPLEMENTATION_PLAN.md
+├── main.go
+├── Dockerfile
+├── .env.example
+├── go.mod / go.sum
+├── cmd/
+│   ├── config.go          # env → Config struct
+│   ├── dotenv.go          # .env loader (dev only)
+│   ├── kafka.go           # setupKafkaConsumer, closeKafkaConsumer
+│   ├── run.go             # Run(), registerGracefulShutdown
+│   └── server.go          # setupRouter (health only)
+└── internal/
+    ├── domain/
+    │   ├── events.go      # consumed topic constants + event structs
+    │   └── service.go     # NotificationService interface
+    ├── email/
+    │   └── smtp_sender.go # EmailSender interface + smtpSender impl
+    ├── events/
+    │   └── kafka_consumer.go  # multi-topic KafkaConsumer
+    ├── handler/
+    │   └── health_handler.go  # GET /health
+    ├── route/
+    │   └── route.go           # RegisterRoutes
+    └── service/
+        └── notification_service.go  # NotificationService impl
+```
+
+---
+
+## Tasks
+
+### Task 1 — Domain: event structs + service interface
+
+**File:** `internal/domain/events.go`
+
+Topic constants for all consumed events:
+```
+TopicUserCreated      = "user.created"
+TopicOrderCreated     = "order.created"
+TopicOrderCancelled   = "order.cancelled"
+TopicPaymentCompleted = "payment.completed"
+TopicPaymentFailed    = "payment.failed"
+TopicInventoryLowStock = "inventory.low_stock"
+```
+
+Event structs (match producing service JSON tags exactly):
+
+- `UserCreatedEvent`   — `id`, `email`, `name`
+- `OrderCreatedEvent`  — `id` (order ID), `user_id`, `total_amount`, `items[]` (`product_id`, `quantity`, `price`)
+- `OrderCancelledEvent`— same shape as `OrderCreatedEvent`
+- `PaymentEvent`       — `id`, `order_id`, `user_id`, `amount`, `currency`, `status`, `failure_reason`
+- `InventoryLowStockEvent` — `product_id`, `total_quantity`, `reserved_quantity`
+
+**File:** `internal/domain/service.go`
+
+```go
+type NotificationService interface {
+    HandleUserCreated(ctx context.Context, event UserCreatedEvent) error
+    HandleOrderCreated(ctx context.Context, event OrderCreatedEvent) error
+    HandleOrderCancelled(ctx context.Context, event OrderCancelledEvent) error
+    HandlePaymentCompleted(ctx context.Context, event PaymentEvent) error
+    HandlePaymentFailed(ctx context.Context, event PaymentEvent) error
+}
+```
+
+---
+
+### Task 2 — Email sender: SMTP client
+
+**File:** `internal/email/smtp_sender.go`
+
+Interface:
+```go
+type EmailSender interface {
+    Send(to, subject, body string) error
+}
+```
+
+Implementation `smtpSender`:
+- Config: `host`, `port`, `from`, `user`, `pass`, `secure bool`
+- Uses `net/smtp` standard library
+- If `user == ""` — use `smtp.SendMail` without auth (relay/MailHog mode for dev)
+- Otherwise — `smtp.PlainAuth` + `smtp.SendMail`
+- Body format: plain-text `Content-Type: text/plain; charset=UTF-8` (no HTML templates for now)
+- Helper `buildMessage(from, to, subject, body string) []byte` — formats RFC 2822 headers
+
+Constructor: `NewSMTPSender(host string, port int, from, user, pass string, secure bool) EmailSender`
+
+---
+
+### Task 3 — Service layer: notification logic
+
+**File:** `internal/service/notification_service.go`
+
+`notificationService` struct — fields: `sender email.EmailSender`
+
+Each handler method:
+1. Composes subject + plain-text body using Go string formatting
+2. Calls `sender.Send(to, subject, body)`
+3. Returns any error
+
+Email content per event:
+
+**HandleUserCreated** — to: `event.Email`
+```
+Subject: Welcome to Auron, {{Name}}!
+Body:    Hi {{Name}}, your account has been created successfully. Start shopping at Auron!
+```
+
+**HandleOrderCreated** — to: derived from `user_id`; problem: no user email in event.
+Resolution: embed the user email in the `OrderCreatedEvent` from the order-service side.  
+For now, log a warning and skip (order-service does not include email — it would require  
+a cross-service call). Store `user_id` in log; send to a no-op target.  
+**Alternative (chosen):** order-service includes `user_email` in the event.  
+Check if order-service event has `user_email`; if not, we skip sending and log.
+
+```
+Subject: Order Confirmed — #{{OrderID}}
+Body:    Your order {{OrderID}} for ${{TotalAmount}} has been placed successfully.
+         Items: (list each product_id × quantity)
+```
+
+**HandleOrderCancelled** — same resolution as above
+```
+Subject: Order Cancelled — #{{OrderID}}
+Body:    Your order {{OrderID}} has been cancelled.
+```
+
+**HandlePaymentCompleted**
+```
+Subject: Payment Received — ${{Amount}} {{Currency}}
+Body:    Your payment of ${{Amount}} {{Currency}} for order {{OrderID}} was successful.
+         Payment ID: {{ID}}
+```
+
+**HandlePaymentFailed**
+```
+Subject: Payment Failed for Order #{{OrderID}}
+Body:    Your payment of ${{Amount}} {{Currency}} for order {{OrderID}} failed.
+         Reason: {{FailureReason}}
+         Please retry or contact support.
+```
+
+> `user_id` from payment events is a UUID — no email available without a user lookup.
+> Payment events from the payment-service include `user_id` (UUID) but NOT email.
+> For the initial implementation: log a warning, skip sending.
+> A follow-up can add a user-service HTTP call to resolve email by user_id.
+
+---
+
+### Task 4 — Kafka consumer: multi-topic consumer
+
+**File:** `internal/events/kafka_consumer.go`
+
+Same pattern as inventory-service: `[]readerEntry` with one `kafka.Reader` per topic.
+
+Topics: `user.created`, `order.created`, `order.cancelled`, `payment.completed`, `payment.failed`, `inventory.low_stock`
+
+Consumer group: `notification-service`
+
+`handleMessage(topic, value []byte)`:
+- Switch on topic
+- Unmarshal into correct event struct
+- Call appropriate `NotificationService` method
+- Log errors, do NOT retry (offset always committed)
+
+`Start(ctx context.Context)` — one goroutine per reader  
+`Close() error` — close all readers
+
+---
+
+### Task 5 — Health handler + route
+
+**File:** `internal/handler/health_handler.go`
+
+```go
+func (h *HealthHandler) GetHealth(c *gin.Context) {
+    c.JSON(200, gin.H{"status": "ok", "service": "notification-service"})
+}
+```
+
+**File:** `internal/route/route.go`
+
+```go
+func RegisterRoutes(router *gin.Engine, healthHandler *handler.HealthHandler) {
+    router.GET("/health", healthHandler.GetHealth)
+}
+```
+
+---
+
+### Task 6 — cmd bootstrap: config, infrastructure, kafka, server, run
+
+**File:** `cmd/config.go`
+
+```go
+type Config struct {
+    Port         string
+    SMTPHost     string
+    SMTPPort     int
+    SMTPFrom     string
+    SMTPUser     string
+    SMTPPass     string
+    SMTPSecure   bool
+    KafkaBrokers []string
+}
+```
+`loadConfig()` reads from env; `KAFKA_BROKERS` splits on `,`.
+
+**File:** `cmd/dotenv.go` — same `.env` loader pattern as other services
+
+**File:** `cmd/kafka.go`
+
+```go
+func setupKafkaConsumer(brokers []string, svc domain.NotificationService) *events.KafkaConsumer
+func startKafkaConsumer(ctx context.Context, consumer *events.KafkaConsumer)
+func closeKafkaConsumer(consumer *events.KafkaConsumer)
+```
+
+**File:** `cmd/server.go` — `setupRouter` (health only, no auth middleware)
+
+**File:** `cmd/run.go` — `Run()` wires everything + `registerGracefulShutdown`
+
+---
+
+### Task 7 — Entry point, Dockerfile, .env.example, docker-compose
+
+**File:** `main.go`
+```go
+package main
+import "auron/notification-service/cmd"
+func main() { cmd.Run() }
+```
+
+**File:** `Dockerfile`
+- `golang:1.25-alpine` builder → `alpine:3.18` runtime
+- Binary: `/notification-service`
+- EXPOSE 8086
+
+**File:** `.env.example`
+```
+PORT=8086
+SMTP_HOST=localhost
+SMTP_PORT=1025
+SMTP_FROM=noreply@auron.shop
+SMTP_USER=
+SMTP_PASS=
+SMTP_SECURE=false
+KAFKA_BROKERS=localhost:9092
+```
+
+**docker-compose.yml** — update `notification-service` stanza:
+- Add `KAFKA_BROKERS=kafka:29092`
+- Add `depends_on: kafka: condition: service_healthy`
+
+---
+
+## Dependencies (go.mod)
+
+```
+github.com/gin-gonic/gin
+github.com/google/uuid
+github.com/segmentio/kafka-go
+github.com/joho/godotenv
+```
+
+No GORM, no Redis — this service has no database or cache.
+
+---
+
+## Design decisions
+
+| Decision | Choice | Reason |
+|----------|--------|--------|
+| No database | Stateless | Emails are fire-and-forget; no state to persist |
+| `net/smtp` not a library | Standard library | No extra dep; plain-text emails are sufficient |
+| Dev mode (no SMTP auth) | `SMTP_USER=""` → no auth | Works with MailHog out of the box |
+| Email for order/payment | Skip if no email in event | Cross-service user lookup adds coupling; deferrable |
+| No retry on Kafka error | Log + commit | Idempotency not guaranteed; prevents consumer stall |
+| Multi-reader consumer | One reader per topic | Same pattern as inventory-service; clean shutdown |
diff --git a/services/notification-service/cmd/config.go b/services/notification-service/cmd/config.go
new file mode 100644
index 0000000..2ab1908
--- /dev/null
+++ b/services/notification-service/cmd/config.go
@@ -0,0 +1,61 @@
+package cmd
+
+import (
+	"os"
+	"strconv"
+)
+
+type appConfig struct {
+	Port         string
+	SMTPHost     string
+	SMTPPort     int
+	SMTPFrom     string
+	SMTPUser     string
+	SMTPPass     string
+	SMTPSecure   bool
+	KafkaBrokers string
+}
+
+func loadConfig() appConfig {
+	loadDotEnvFile(".env")
+
+	port := os.Getenv("PORT")
+	if port == "" {
+		port = "8086"
+	}
+
+	smtpHost := os.Getenv("SMTP_HOST")
+	if smtpHost == "" {
+		smtpHost = "localhost"
+	}
+
+	smtpPort := 1025
+	if v := os.Getenv("SMTP_PORT"); v != "" {
+		if p, err := strconv.Atoi(v); err == nil {
+			smtpPort = p
+		}
+	}
+
+	smtpFrom := os.Getenv("SMTP_FROM")
+	if smtpFrom == "" {
+		smtpFrom = "noreply@auron.shop"
+	}
+
+	smtpSecure := os.Getenv("SMTP_SECURE") == "true"
+
+	kafkaBrokers := os.Getenv("KAFKA_BROKERS")
+	if kafkaBrokers == "" {
+		kafkaBrokers = "localhost:9092"
+	}
+
+	return appConfig{
+		Port:         port,
+		SMTPHost:     smtpHost,
+		SMTPPort:     smtpPort,
+		SMTPFrom:     smtpFrom,
+		SMTPUser:     os.Getenv("SMTP_USER"),
+		SMTPPass:     os.Getenv("SMTP_PASS"),
+		SMTPSecure:   smtpSecure,
+		KafkaBrokers: kafkaBrokers,
+	}
+}
diff --git a/services/notification-service/cmd/dotenv.go b/services/notification-service/cmd/dotenv.go
new file mode 100644
index 0000000..3c652db
--- /dev/null
+++ b/services/notification-service/cmd/dotenv.go
@@ -0,0 +1,42 @@
+package cmd
+
+import (
+	"bufio"
+	"os"
+	"strings"
+)
+
+func loadDotEnvFile(path string) {
+	file, err := os.Open(path)
+	if err != nil {
+		return
+	}
+	defer file.Close()
+
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		line := strings.TrimSpace(scanner.Text())
+		if line == "" || strings.HasPrefix(line, "#") {
+			continue
+		}
+
+		parts := strings.SplitN(line, "=", 2)
+		if len(parts) != 2 {
+			continue
+		}
+
+		key := strings.TrimSpace(parts[0])
+		value := strings.TrimSpace(parts[1])
+		value = strings.Trim(value, `"'`)
+
+		if key == "" {
+			continue
+		}
+
+		if _, exists := os.LookupEnv(key); exists {
+			continue
+		}
+
+		_ = os.Setenv(key, value)
+	}
+}
diff --git a/services/notification-service/cmd/kafka.go b/services/notification-service/cmd/kafka.go
new file mode 100644
index 0000000..8af5e47
--- /dev/null
+++ b/services/notification-service/cmd/kafka.go
@@ -0,0 +1,50 @@
+package cmd
+
+import (
+	"context"
+	"log/slog"
+	"strings"
+
+	"auron/notification-service/internal/domain"
+	"auron/notification-service/internal/events"
+)
+
+func setupKafkaConsumer(kafkaBrokers string, svc domain.NotificationService) *events.KafkaConsumer {
+	brokers := parseBrokers(kafkaBrokers)
+	return events.NewKafkaConsumer(brokers, svc)
+}
+
+func startKafkaConsumer(ctx context.Context, consumer *events.KafkaConsumer) {
+	consumer.Start(ctx)
+	slog.Info("kafka consumer started",
+		"topics", []string{
+			domain.TopicUserCreated,
+			domain.TopicOrderCreated,
+			domain.TopicOrderCancelled,
+			domain.TopicPaymentCompleted,
+			domain.TopicPaymentFailed,
+			domain.TopicInventoryLowStock,
+		},
+		"group", "notification-service",
+	)
+}
+
+func closeKafkaConsumer(consumer *events.KafkaConsumer) {
+	if err := consumer.Close(); err != nil {
+		slog.Warn("failed to close kafka consumer", "error", err)
+	}
+}
+
+func parseBrokers(kafkaBrokers string) []string {
+	parts := strings.Split(kafkaBrokers, ",")
+	brokers := make([]string, 0, len(parts))
+	for _, b := range parts {
+		if trimmed := strings.TrimSpace(b); trimmed != "" {
+			brokers = append(brokers, trimmed)
+		}
+	}
+	if len(brokers) == 0 {
+		return []string{"localhost:9092"}
+	}
+	return brokers
+}
diff --git a/services/notification-service/cmd/run.go b/services/notification-service/cmd/run.go
new file mode 100644
index 0000000..a06b6bf
--- /dev/null
+++ b/services/notification-service/cmd/run.go
@@ -0,0 +1,51 @@
+package cmd
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"auron/notification-service/internal/email"
+	"auron/notification-service/internal/events"
+	"auron/notification-service/internal/handler"
+	"auron/notification-service/internal/service"
+)
+
+func Run() {
+	cfg := loadConfig()
+
+	sender := email.NewSMTPSender(cfg.SMTPHost, cfg.SMTPPort, cfg.SMTPFrom, cfg.SMTPUser, cfg.SMTPPass, cfg.SMTPSecure)
+
+	notificationSvc := service.NewNotificationService(sender)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	consumer := setupKafkaConsumer(cfg.KafkaBrokers, notificationSvc)
+	startKafkaConsumer(ctx, consumer)
+
+	healthHandler := handler.NewHealthHandler()
+	router := setupRouter(healthHandler)
+
+	registerGracefulShutdown(consumer, cancel)
+
+	addr := fmt.Sprintf(":%s", cfg.Port)
+	log.Printf("starting notification-service on %s", addr)
+	if err := router.Run(addr); err != nil {
+		log.Fatalf("failed to start server: %v", err)
+	}
+}
+
+func registerGracefulShutdown(consumer *events.KafkaConsumer, cancel context.CancelFunc) {
+	quit := make(chan os.Signal, 1)
+	signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)
+
+	go func() {
+		<-quit
+		fmt.Println("\nshutting down notification-service...")
+		cancel()
+		closeKafkaConsumer(consumer)
+		os.Exit(0)
+	}()
+}
diff --git a/services/notification-service/cmd/server.go b/services/notification-service/cmd/server.go
new file mode 100644
index 0000000..b528246
--- /dev/null
+++ b/services/notification-service/cmd/server.go
@@ -0,0 +1,19 @@
+package cmd
+
+import (
+	"auron/notification-service/internal/handler"
+	"auron/notification-service/internal/route"
+
+	"github.com/gin-gonic/gin"
+)
+
+func setupRouter(healthHandler *handler.HealthHandler) *gin.Engine {
+	gin.SetMode(gin.ReleaseMode)
+	router := gin.New()
+	router.Use(gin.Logger())
+	router.Use(gin.Recovery())
+
+	route.RegisterRoutes(router, healthHandler)
+
+	return router
+}
diff --git a/services/notification-service/go.mod b/services/notification-service/go.mod
new file mode 100644
index 0000000..4c2207e
--- /dev/null
+++ b/services/notification-service/go.mod
@@ -0,0 +1,43 @@
+module auron/notification-service
+
+go 1.25.8
+
+require (
+	github.com/gin-gonic/gin v1.12.0
+	github.com/google/uuid v1.6.0
+	github.com/segmentio/kafka-go v0.4.47
+)
+
+require (
+	github.com/bytedance/gopkg v0.1.3 // indirect
+	github.com/bytedance/sonic v1.15.0 // indirect
+	github.com/bytedance/sonic/loader v0.5.0 // indirect
+	github.com/cloudwego/base64x v0.1.6 // indirect
+	github.com/gabriel-vasile/mimetype v1.4.12 // indirect
+	github.com/gin-contrib/sse v1.1.0 // indirect
+	github.com/go-playground/locales v0.14.1 // indirect
+	github.com/go-playground/universal-translator v0.18.1 // indirect
+	github.com/go-playground/validator/v10 v10.30.1 // indirect
+	github.com/goccy/go-json v0.10.5 // indirect
+	github.com/goccy/go-yaml v1.19.2 // indirect
+	github.com/json-iterator/go v1.1.12 // indirect
+	github.com/klauspost/compress v1.17.6 // indirect
+	github.com/klauspost/cpuid/v2 v2.3.0 // indirect
+	github.com/leodido/go-urn v1.4.0 // indirect
+	github.com/mattn/go-isatty v0.0.20 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.2 // indirect
+	github.com/pelletier/go-toml/v2 v2.2.4 // indirect
+	github.com/pierrec/lz4/v4 v4.1.15 // indirect
+	github.com/quic-go/qpack v0.6.0 // indirect
+	github.com/quic-go/quic-go v0.59.0 // indirect
+	github.com/twitchyliquid64/golang-asm v0.15.1 // indirect
+	github.com/ugorji/go/codec v1.3.1 // indirect
+	go.mongodb.org/mongo-driver/v2 v2.5.0 // indirect
+	golang.org/x/arch v0.22.0 // indirect
+	golang.org/x/crypto v0.48.0 // indirect
+	golang.org/x/net v0.51.0 // indirect
+	golang.org/x/sys v0.41.0 // indirect
+	golang.org/x/text v0.34.0 // indirect
+	google.golang.org/protobuf v1.36.10 // indirect
+)
diff --git a/services/notification-service/go.sum b/services/notification-service/go.sum
new file mode 100644
index 0000000..2f5dd17
--- /dev/null
+++ b/services/notification-service/go.sum
@@ -0,0 +1,145 @@
+github.com/bytedance/gopkg v0.1.3 h1:TPBSwH8RsouGCBcMBktLt1AymVo2TVsBVCY4b6TnZ/M=
+github.com/bytedance/gopkg v0.1.3/go.mod h1:576VvJ+eJgyCzdjS+c4+77QF3p7ubbtiKARP3TxducM=
+github.com/bytedance/sonic v1.15.0 h1:/PXeWFaR5ElNcVE84U0dOHjiMHQOwNIx3K4ymzh/uSE=
+github.com/bytedance/sonic v1.15.0/go.mod h1:tFkWrPz0/CUCLEF4ri4UkHekCIcdnkqXw9VduqpJh0k=
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+golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+google.golang.org/protobuf v1.36.10 h1:AYd7cD/uASjIL6Q9LiTjz8JLcrh/88q5UObnmY3aOOE=
+google.golang.org/protobuf v1.36.10/go.mod h1:HTf+CrKn2C3g5S8VImy6tdcUvCska2kB7j23XfzDpco=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
diff --git a/services/notification-service/internal/domain/events.go b/services/notification-service/internal/domain/events.go
new file mode 100644
index 0000000..00b7ca7
--- /dev/null
+++ b/services/notification-service/internal/domain/events.go
@@ -0,0 +1,64 @@
+package domain
+
+import (
+	"time"
+
+	"github.com/google/uuid"
+)
+
+const (
+	TopicUserCreated       = "user.created"
+	TopicOrderCreated      = "order.created"
+	TopicOrderCancelled    = "order.cancelled"
+	TopicPaymentCompleted  = "payment.completed"
+	TopicPaymentFailed     = "payment.failed"
+	TopicInventoryLowStock = "inventory.low_stock"
+)
+
+// UserCreatedEvent matches the User struct published by user-service (json tags on domain.User).
+type UserCreatedEvent struct {
+	ID    uuid.UUID `json:"id"`
+	Email string    `json:"email"`
+	Name  string    `json:"name"`
+	Role  string    `json:"role"`
+}
+
+// OrderEvent matches the Order struct published by order-service.
+// Both order.created and order.cancelled use the same payload shape.
+type OrderEvent struct {
+	ID              uuid.UUID        `json:"id"`
+	UserID          uuid.UUID        `json:"user_id"`
+	Status          string           `json:"status"`
+	TotalAmount     float64          `json:"total_amount"`
+	ShippingName    string           `json:"shipping_name"`
+	ShippingAddress string           `json:"shipping_address"`
+	Items           []OrderEventItem `json:"items"`
+	CreatedAt       time.Time        `json:"created_at"`
+}
+
+type OrderEventItem struct {
+	ProductID   uuid.UUID `json:"product_id"`
+	ProductName string    `json:"product_name"`
+	Price       float64   `json:"price"`
+	Quantity    int       `json:"quantity"`
+	Subtotal    float64   `json:"subtotal"`
+}
+
+// PaymentEvent matches the PaymentResponse struct published by payment-service.
+type PaymentEvent struct {
+	ID            uuid.UUID `json:"id"`
+	OrderID       uuid.UUID `json:"order_id"`
+	UserID        uuid.UUID `json:"user_id"`
+	Amount        float64   `json:"amount"`
+	Currency      string    `json:"currency"`
+	Status        string    `json:"status"`
+	FailureReason string    `json:"failure_reason,omitempty"`
+}
+
+// InventoryLowStockEvent matches the InventoryResponse struct published by inventory-service.
+type InventoryLowStockEvent struct {
+	ProductID         uuid.UUID `json:"product_id"`
+	TotalQuantity     int       `json:"total_quantity"`
+	ReservedQuantity  int       `json:"reserved_quantity"`
+	AvailableQuantity int       `json:"available_quantity"`
+}
diff --git a/services/notification-service/internal/domain/service.go b/services/notification-service/internal/domain/service.go
new file mode 100644
index 0000000..a9fb97c
--- /dev/null
+++ b/services/notification-service/internal/domain/service.go
@@ -0,0 +1,11 @@
+package domain
+
+import "context"
+
+type NotificationService interface {
+	HandleUserCreated(ctx context.Context, event UserCreatedEvent) error
+	HandleOrderCreated(ctx context.Context, event OrderEvent) error
+	HandleOrderCancelled(ctx context.Context, event OrderEvent) error
+	HandlePaymentCompleted(ctx context.Context, event PaymentEvent) error
+	HandlePaymentFailed(ctx context.Context, event PaymentEvent) error
+}
diff --git a/services/notification-service/internal/email/smtp_sender.go b/services/notification-service/internal/email/smtp_sender.go
new file mode 100644
index 0000000..1b42ed2
--- /dev/null
+++ b/services/notification-service/internal/email/smtp_sender.go
@@ -0,0 +1,49 @@
+package email
+
+import (
+	"fmt"
+	"net/smtp"
+)
+
+type EmailSender interface {
+	Send(to, subject, body string) error
+}
+
+type smtpSender struct {
+	host   string
+	port   int
+	from   string
+	user   string
+	pass   string
+	secure bool
+}
+
+func NewSMTPSender(host string, port int, from, user, pass string, secure bool) EmailSender {
+	return &smtpSender{
+		host:   host,
+		port:   port,
+		from:   from,
+		user:   user,
+		pass:   pass,
+		secure: secure,
+	}
+}
+
+func (s *smtpSender) Send(to, subject, body string) error {
+	addr := fmt.Sprintf("%s:%d", s.host, s.port)
+	msg := buildMessage(s.from, to, subject, body)
+
+	if s.user == "" {
+		return smtp.SendMail(addr, nil, s.from, []string{to}, msg)
+	}
+
+	auth := smtp.PlainAuth("", s.user, s.pass, s.host)
+	return smtp.SendMail(addr, auth, s.from, []string{to}, msg)
+}
+
+func buildMessage(from, to, subject, body string) []byte {
+	return []byte(fmt.Sprintf(
+		"From: %s\r\nTo: %s\r\nSubject: %s\r\nContent-Type: text/plain; charset=UTF-8\r\n\r\n%s",
+		from, to, subject, body,
+	))
+}
diff --git a/services/notification-service/internal/events/kafka_consumer.go b/services/notification-service/internal/events/kafka_consumer.go
new file mode 100644
index 0000000..a77e2fb
--- /dev/null
+++ b/services/notification-service/internal/events/kafka_consumer.go
@@ -0,0 +1,134 @@
+package events
+
+import (
+	"context"
+	"encoding/json"
+	"log/slog"
+
+	"auron/notification-service/internal/domain"
+
+	"github.com/segmentio/kafka-go"
+)
+
+type readerEntry struct {
+	reader *kafka.Reader
+	topic  string
+}
+
+type KafkaConsumer struct {
+	readers []readerEntry
+	service domain.NotificationService
+}
+
+func NewKafkaConsumer(brokers []string, svc domain.NotificationService) *KafkaConsumer {
+	topics := []string{
+		domain.TopicUserCreated,
+		domain.TopicOrderCreated,
+		domain.TopicOrderCancelled,
+		domain.TopicPaymentCompleted,
+		domain.TopicPaymentFailed,
+		domain.TopicInventoryLowStock,
+	}
+
+	readers := make([]readerEntry, 0, len(topics))
+	for _, topic := range topics {
+		r := kafka.NewReader(kafka.ReaderConfig{
+			Brokers:  brokers,
+			Topic:    topic,
+			GroupID:  "notification-service",
+			MinBytes: 1,
+			MaxBytes: 10e6,
+		})
+		readers = append(readers, readerEntry{reader: r, topic: topic})
+	}
+
+	return &KafkaConsumer{readers: readers, service: svc}
+}
+
+func (c *KafkaConsumer) Start(ctx context.Context) {
+	for _, entry := range c.readers {
+		go c.consumeTopic(ctx, entry)
+	}
+}
+
+func (c *KafkaConsumer) Close() error {
+	var lastErr error
+	for _, entry := range c.readers {
+		if err := entry.reader.Close(); err != nil {
+			lastErr = err
+		}
+	}
+	return lastErr
+}
+
+func (c *KafkaConsumer) consumeTopic(ctx context.Context, entry readerEntry) {
+	for {
+		msg, err := entry.reader.ReadMessage(ctx)
+		if err != nil {
+			if ctx.Err() != nil {
+				return
+			}
+			slog.Error("kafka read error", "topic", entry.topic, "error", err)
+			continue
+		}
+		c.handleMessage(ctx, entry.topic, msg.Value)
+	}
+}
+
+func (c *KafkaConsumer) handleMessage(ctx context.Context, topic string, value []byte) {
+	var err error
+	switch topic {
+	case domain.TopicUserCreated:
+		var event domain.UserCreatedEvent
+		if err = json.Unmarshal(value, &event); err != nil {
+			break
+		}
+		err = c.service.HandleUserCreated(ctx, event)
+
+	case domain.TopicOrderCreated:
+		var event domain.OrderEvent
+		if err = json.Unmarshal(value, &event); err != nil {
+			break
+		}
+		err = c.service.HandleOrderCreated(ctx, event)
+
+	case domain.TopicOrderCancelled:
+		var event domain.OrderEvent
+		if err = json.Unmarshal(value, &event); err != nil {
+			break
+		}
+		err = c.service.HandleOrderCancelled(ctx, event)
+
+	case domain.TopicPaymentCompleted:
+		var event domain.PaymentEvent
+		if err = json.Unmarshal(value, &event); err != nil {
+			break
+		}
+		err = c.service.HandlePaymentCompleted(ctx, event)
+
+	case domain.TopicPaymentFailed:
+		var event domain.PaymentEvent
+		if err = json.Unmarshal(value, &event); err != nil {
+			break
+		}
+		err = c.service.HandlePaymentFailed(ctx, event)
+
+	case domain.TopicInventoryLowStock:
+		var event domain.InventoryLowStockEvent
+		if err = json.Unmarshal(value, &event); err != nil {
+			break
+		}
+		slog.Warn("inventory low stock",
+			"product_id", event.ProductID,
+			"available", event.AvailableQuantity,
+			"total", event.TotalQuantity,
+		)
+
+	default:
+		slog.Warn("kafka consumer received unknown topic", "topic", topic)
+	}
+
+	if err != nil {
+		slog.Error("failed to handle kafka message", "topic", topic, "error", err)
+	}
+}
diff --git a/services/notification-service/internal/handler/health_handler.go b/services/notification-service/internal/handler/health_handler.go
new file mode 100644
index 0000000..da18fd5
--- /dev/null
+++ b/services/notification-service/internal/handler/health_handler.go
@@ -0,0 +1,21 @@
+package handler
+
+import (
+	"time"
+
+	"github.com/gin-gonic/gin"
+)
+
+type HealthHandler struct{}
+
+func NewHealthHandler() *HealthHandler {
+	return &HealthHandler{}
+}
+
+func (h *HealthHandler) GetHealth(c *gin.Context) {
+	c.JSON(200, gin.H{
+		"status":    "healthy",
+		"service":   "notification-service",
+		"timestamp": time.Now().UTC(),
+	})
+}
diff --git a/services/notification-service/internal/route/route.go b/services/notification-service/internal/route/route.go
new file mode 100644
index 0000000..63e48cd
--- /dev/null
+++ b/services/notification-service/internal/route/route.go
@@ -0,0 +1,11 @@
+package route
+
+import (
+	"auron/notification-service/internal/handler"
+
+	"github.com/gin-gonic/gin"
+)
+
+func RegisterRoutes(router *gin.Engine, healthHandler *handler.HealthHandler) {
+	router.GET("/health", healthHandler.GetHealth)
+}
diff --git a/services/notification-service/internal/service/notification_service.go b/services/notification-service/internal/service/notification_service.go
new file mode 100644
index 0000000..ab704ed
--- /dev/null
+++ b/services/notification-service/internal/service/notification_service.go
@@ -0,0 +1,70 @@
+package service
+
+import (
+	"context"
+	"fmt"
+	"log/slog"
+	"strings"
+
+	"auron/notification-service/internal/domain"
+	"auron/notification-service/internal/email"
+)
+
+type notificationService struct {
+	sender email.EmailSender
+}
+
+func NewNotificationService(sender email.EmailSender) domain.NotificationService {
+	return &notificationService{sender: sender}
+}
+
+func (s *notificationService) HandleUserCreated(_ context.Context, event domain.UserCreatedEvent) error {
+	subject := fmt.Sprintf("Welcome to Auron, %s!", event.Name)
+	body := fmt.Sprintf(
+		"Hi %s,\n\nYour account has been created successfully.\nStart shopping at Auron!\n\nWelcome aboard,\nThe Auron Team",
+		event.Name,
+	)
+	return s.sender.Send(event.Email, subject, body)
+}
+
+func (s *notificationService) HandleOrderCreated(_ context.Context, event domain.OrderEvent) error {
+	// order.created payload is the raw Order struct — no user email included.
+	// Log and skip; a follow-up can add a user-service lookup to resolve email.
+	slog.Info("order.created received — no user email in event, skipping notification",
+		"order_id", event.ID,
+		"user_id", event.UserID,
+		"total_amount", event.TotalAmount,
+	)
+	return nil
+}
+
+func (s *notificationService) HandleOrderCancelled(_ context.Context, event domain.OrderEvent) error {
+	// Same constraint as HandleOrderCreated — no user email in the event payload.
+	slog.Info("order.cancelled received — no user email in event, skipping notification",
+		"order_id", event.ID,
+		"user_id", event.UserID,
+	)
+	return nil
+}
+
+func (s *notificationService) HandlePaymentCompleted(_ context.Context, event domain.PaymentEvent) error {
+	// payment.completed carries user_id (UUID) but not the user's email.
+	// Log for now; a follow-up can resolve email via user-service HTTP call.
+	slog.Info("payment.completed received — no user email in event, skipping notification",
+		"payment_id", event.ID,
+		"order_id", event.OrderID,
+		"user_id", event.UserID,
+		"amount", fmt.Sprintf("%.2f %s", event.Amount, strings.ToUpper(event.Currency)),
+	)
+	return nil
+}
+
+func (s *notificationService) HandlePaymentFailed(_ context.Context, event domain.PaymentEvent) error {
+	slog.Info("payment.failed received — no user email in event, skipping notification",
+		"payment_id", event.ID,
+		"order_id", event.OrderID,
+		"user_id", event.UserID,
+		"reason", event.FailureReason,
+	)
+	return nil
+}
diff --git a/services/notification-service/main.go b/services/notification-service/main.go
new file mode 100644
index 0000000..1968cf4
--- /dev/null
+++ b/services/notification-service/main.go
@@ -0,0 +1,7 @@
+package main
+
+import "auron/notification-service/cmd"
+
+func main() {
+	cmd.Run()
+}