diff --git a/services/ads-serving-service-net/src/AdsServingService.API/Application/Events/AdServingEventPublisher.cs b/services/ads-serving-service-net/src/AdsServingService.API/Application/Events/AdServingEventPublisher.cs
new file mode 100644
index 00000000..8aa8dca4
--- /dev/null
+++ b/services/ads-serving-service-net/src/AdsServingService.API/Application/Events/AdServingEventPublisher.cs
@@ -0,0 +1,102 @@
+namespace AdsServingService.API.Application.Events;
+
+/// <summary>
+/// EN: Event payload for served-ad event.
+/// VI: Payload event cho sự kiện quảng cáo đã được phục vụ.
+/// </summary>
+public record AdServedEvent
+{
+    public Guid AuctionId { get; init; }
+    public Guid AdId { get; init; }
+    public Guid CampaignId { get; init; }
+    public Guid UserId { get; init; }
+    public string PlacementType { get; init; } = string.Empty;
+    public decimal FinalPrice { get; init; }
+    public decimal WinningEcpm { get; init; }
+    public DateTime ServedAt { get; init; }
+}
+
+/// <summary>
+/// EN: Event payload for impression.
+/// VI: Payload event cho impression.
+/// </summary>
+public record AdImpressionTrackedEvent
+{
+    public Guid AdId { get; init; }
+    public Guid UserId { get; init; }
+    public DateTime Timestamp { get; init; }
+}
+
+/// <summary>
+/// EN: Event payload for click.
+/// VI: Payload event cho click.
+/// </summary>
+public record AdClickTrackedEvent
+{
+    public Guid AdId { get; init; }
+    public Guid UserId { get; init; }
+    public DateTime Timestamp { get; init; }
+}
+
+/// <summary>
+/// EN: Abstraction for publishing ads-serving events asynchronously.
+/// VI: Abstraction để publish bất đồng bộ các sự kiện ads-serving.
+/// </summary>
+public interface IAdServingEventPublisher
+{
+    Task PublishAdServedAsync(AdServedEvent payload, CancellationToken cancellationToken);
+    Task PublishImpressionTrackedAsync(AdImpressionTrackedEvent payload, CancellationToken cancellationToken);
+    Task PublishClickTrackedAsync(AdClickTrackedEvent payload, CancellationToken cancellationToken);
+}
+
+/// <summary>
+/// EN: Logging-based publisher used as default implementation.
+/// VI: Publisher dựa trên logging dùng làm implementation mặc định.
+/// </summary>
+public class LoggingAdServingEventPublisher : IAdServingEventPublisher
+{
+    private readonly ILogger<LoggingAdServingEventPublisher> _logger;
+
+    public LoggingAdServingEventPublisher(ILogger<LoggingAdServingEventPublisher> logger)
+    {
+        _logger = logger ?? throw new ArgumentNullException(nameof(logger));
+    }
+
+    public Task PublishAdServedAsync(AdServedEvent payload, CancellationToken cancellationToken)
+    {
+        _logger.LogInformation(
+            "ad.served.v1 event published: AuctionId={AuctionId}, AdId={AdId}, CampaignId={CampaignId}, UserId={UserId}, PlacementType={PlacementType}, FinalPrice={FinalPrice}, WinningEcpm={WinningEcpm}, ServedAt={ServedAt}",
+            payload.AuctionId,
+            payload.AdId,
+            payload.CampaignId,
+            payload.UserId,
+            payload.PlacementType,
+            payload.FinalPrice,
+            payload.WinningEcpm,
+            payload.ServedAt);
+
+        return Task.CompletedTask;
+    }
+
+    public Task PublishImpressionTrackedAsync(AdImpressionTrackedEvent payload, CancellationToken cancellationToken)
+    {
+        _logger.LogInformation(
+            "ads.impression.tracked.v1 event published: AdId={AdId}, UserId={UserId}, Timestamp={Timestamp}",
+            payload.AdId,
+            payload.UserId,
+            payload.Timestamp);
+
+        return Task.CompletedTask;
+    }
+
+    public Task PublishClickTrackedAsync(AdClickTrackedEvent payload, CancellationToken cancellationToken)
+    {
+        _logger.LogInformation(
+            "ads.click.tracked.v1 event published: AdId={AdId}, UserId={UserId}, Timestamp={Timestamp}",
+            payload.AdId,
+            payload.UserId,
+            payload.Timestamp);
+
+        return Task.CompletedTask;
+    }
+}
diff --git a/services/ads-serving-service-net/src/AdsServingService.API/Application/Queries/GetAuctionStatisticsQuery.cs b/services/ads-serving-service-net/src/AdsServingService.API/Application/Queries/GetAuctionStatisticsQuery.cs
new file mode 100644
index 00000000..0450142a
--- /dev/null
+++ b/services/ads-serving-service-net/src/AdsServingService.API/Application/Queries/GetAuctionStatisticsQuery.cs
@@ -0,0 +1,21 @@
+using MediatR;
+
+namespace AdsServingService.API.Application.Queries;
+
+/// <summary>
+/// EN: Query to retrieve aggregate auction statistics.
+/// VI: Query để lấy thống kê tổng hợp của auction.
+/// </summary>
+public record GetAuctionStatisticsQuery : IRequest<AuctionStatisticsDto>;
+
+/// <summary>
+/// EN: Aggregate auction statistics DTO.
+/// VI: DTO thống kê tổng hợp auction.
+/// </summary>
+public record AuctionStatisticsDto
+{
+    public int TotalAuctions { get; init; }
+    public decimal AverageWinRate { get; init; }
+    public decimal AverageeCPM { get; init; }
+    public long TotalBidsPlaced { get; init; }
+}
diff --git a/services/ads-serving-service-net/src/AdsServingService.API/Application/Queries/GetAuctionStatisticsQueryHandler.cs b/services/ads-serving-service-net/src/AdsServingService.API/Application/Queries/GetAuctionStatisticsQueryHandler.cs
new file mode 100644
index 00000000..f364a800
--- /dev/null
+++ b/services/ads-serving-service-net/src/AdsServingService.API/Application/Queries/GetAuctionStatisticsQueryHandler.cs
@@ -0,0 +1,82 @@
+using System.Text.Json;
+using AdsServingService.Infrastructure;
+using MediatR;
+using Microsoft.EntityFrameworkCore;
+
+namespace AdsServingService.API.Application.Queries;
+
+/// <summary>
+/// EN: Handler for GetAuctionStatisticsQuery.
+/// VI: Handler cho GetAuctionStatisticsQuery.
+/// </summary>
+public class GetAuctionStatisticsQueryHandler
+    : IRequestHandler<GetAuctionStatisticsQuery, AuctionStatisticsDto>
+{
+    private readonly AdsServingServiceContext _context;
+
+    public GetAuctionStatisticsQueryHandler(AdsServingServiceContext context)
+    {
+        _context = context ?? throw new ArgumentNullException(nameof(context));
+    }
+
+    public async Task<AuctionStatisticsDto> Handle(
+        GetAuctionStatisticsQuery request,
+        CancellationToken cancellationToken)
+    {
+        var auctionSnapshots = await _context.Auctions
+            .AsNoTracking()
+            .Select(auction => new
+            {
+                HasWinner = auction.Result != null,
+                WinningEcpm = auction.Result != null ? auction.Result.WinningeCPM : 0m,
+                BidsJson = EF.Property<string>(auction, "_bidsJson"),
+            })
+            .ToListAsync(cancellationToken);
+
+        var totalAuctions = auctionSnapshots.Count;
+        var totalWinners = auctionSnapshots.Count(snapshot => snapshot.HasWinner);
+        var averageWinRate = totalAuctions == 0
+            ? 0m
+            : Math.Round((decimal)totalWinners / totalAuctions * 100m, 2);
+
+        var winningEcpmValues = auctionSnapshots
+            .Where(snapshot => snapshot.HasWinner)
+            .Select(snapshot => snapshot.WinningEcpm)
+            .ToList();
+
+        var averageEcpm = winningEcpmValues.Count == 0
+            ? 0m
+            : Math.Round(winningEcpmValues.Average(), 4);
+
+        var totalBidsPlaced = auctionSnapshots
+            .Sum(snapshot => CountBids(snapshot.BidsJson));
+
+        return new AuctionStatisticsDto
+        {
+            TotalAuctions = totalAuctions,
+            AverageWinRate = averageWinRate,
+            AverageeCPM = averageEcpm,
+            TotalBidsPlaced = totalBidsPlaced,
+        };
+    }
+
+    private static int CountBids(string? bidsJson)
+    {
+        if (string.IsNullOrWhiteSpace(bidsJson))
+        {
+            return 0;
+        }
+
+        try
+        {
+            using var document = JsonDocument.Parse(bidsJson);
+            return document.RootElement.ValueKind == JsonValueKind.Array
+                ? document.RootElement.GetArrayLength()
+                : 0;
+        }
+        catch (JsonException)
+        {
+            return 0;
+        }
+    }
+}
diff --git a/services/ads-serving-service-net/src/AdsServingService.API/Application/Queries/GetAuctionsQueryHandler.cs b/services/ads-serving-service-net/src/AdsServingService.API/Application/Queries/GetAuctionsQueryHandler.cs
index 1602e908..92308f7c 100644
--- a/services/ads-serving-service-net/src/AdsServingService.API/Application/Queries/GetAuctionsQueryHandler.cs
+++ b/services/ads-serving-service-net/src/AdsServingService.API/Application/Queries/GetAuctionsQueryHandler.cs
@@ -1,6 +1,7 @@
 using AdsServingService.Infrastructure;
 using MediatR;
 using Microsoft.EntityFrameworkCore;
+using System.Text.Json;
 
 namespace AdsServingService.API.Application.Queries;
 
@@ -42,25 +43,59 @@ public class GetAuctionsQueryHandler : IRequestHandler<GetAuctionsQuery, PagedRe
             .OrderByDescending(a => EF.Property<DateTime>(a, "_auctionTime"))
             .Skip((request.Page - 1) * request.PageSize)
             .Take(request.PageSize)
-            .Select(a => new AuctionDto
+            .Select(a => new
             {
                 Id = a.Id,
                 UserId = a.UserId,
                 PlacementType = a.PlacementType,
                 AuctionTime = EF.Property<DateTime>(a, "_auctionTime"),
-                BidCount = a.Bids.Count,
+                BidsJson = EF.Property<string>(a, "_bidsJson"),
                 WinningAdId = a.Result != null ? a.Result.WinningAdId : null,
                 FinalPrice = a.Result != null ? a.Result.FinalPrice : null,
                 WinningeCPM = a.Result != null ? a.Result.WinningeCPM : null
             })
             .ToListAsync(cancellationToken);
 
+        var items = auctions
+            .Select(a => new AuctionDto
+            {
+                Id = a.Id,
+                UserId = a.UserId,
+                PlacementType = a.PlacementType,
+                AuctionTime = a.AuctionTime,
+                BidCount = CountBids(a.BidsJson),
+                WinningAdId = a.WinningAdId,
+                FinalPrice = a.FinalPrice,
+                WinningeCPM = a.WinningeCPM,
+            })
+            .ToList();
+
         return new PagedResult<AuctionDto>
         {
-            Items = auctions,
+            Items = items,
             TotalCount = totalCount,
             Page = request.Page,
             PageSize = request.PageSize
         };
     }
+
+    private static int CountBids(string? bidsJson)
+    {
+        if (string.IsNullOrWhiteSpace(bidsJson))
+        {
+            return 0;
+        }
+
+        try
+        {
+            using var document = JsonDocument.Parse(bidsJson);
+            return document.RootElement.ValueKind == JsonValueKind.Array
+                ? document.RootElement.GetArrayLength()
+                : 0;
+        }
+        catch (JsonException)
+        {
+            return 0;
+        }
+    }
 }
diff --git a/services/ads-serving-service-net/src/AdsServingService.API/Application/Queries/ServeAdQueryHandler.cs b/services/ads-serving-service-net/src/AdsServingService.API/Application/Queries/ServeAdQueryHandler.cs
index 04e556d3..dfd71ee1 100644
--- a/services/ads-serving-service-net/src/AdsServingService.API/Application/Queries/ServeAdQueryHandler.cs
+++ b/services/ads-serving-service-net/src/AdsServingService.API/Application/Queries/ServeAdQueryHandler.cs
@@ -1,4 +1,8 @@
 using AdsServingService.Domain.AggregatesModel.AuctionAggregate;
+using AdsServingService.API.Application.Events;
+using AdsServingService.API.Application.Services;
+using AdsServingService.Infrastructure;
+using System.Text.Json;
 using MediatR;
 
 namespace AdsServingService.API.Application.Queries;
@@ -9,10 +13,23 @@ namespace AdsServingService.API.Application.Queries;
 /// </summary>
 public class ServeAdQueryHandler : IRequestHandler<ServeAdQuery, ServedAdDto?>
 {
+    private readonly AdsServingServiceContext _context;
+    private readonly IEligibleAdsProvider _eligibleAdsProvider;
+    private readonly IAuctionScoringService _auctionScoringService;
+    private readonly IAdServingEventPublisher _eventPublisher;
     private readonly ILogger<ServeAdQueryHandler> _logger;
 
-    public ServeAdQueryHandler(ILogger<ServeAdQueryHandler> logger)
+    public ServeAdQueryHandler(
+        AdsServingServiceContext context,
+        IEligibleAdsProvider eligibleAdsProvider,
+        IAuctionScoringService auctionScoringService,
+        IAdServingEventPublisher eventPublisher,
+        ILogger<ServeAdQueryHandler> logger)
     {
+        _context = context ?? throw new ArgumentNullException(nameof(context));
+        _eligibleAdsProvider = eligibleAdsProvider ?? throw new ArgumentNullException(nameof(eligibleAdsProvider));
+        _auctionScoringService = auctionScoringService ?? throw new ArgumentNullException(nameof(auctionScoringService));
+        _eventPublisher = eventPublisher ?? throw new ArgumentNullException(nameof(eventPublisher));
         _logger = logger ?? throw new ArgumentNullException(nameof(logger));
     }
 
@@ -22,9 +39,11 @@ public class ServeAdQueryHandler : IRequestHandler<ServeAdQuery, ServedAdDto?>
 
         try
         {
-            // TODO: Step 1 - Fetch eligible ads from cache/database
-            // For now, mock data for demonstration
-            var eligibleAds = GetMockEligibleAds(request.PlacementType);
+            var eligibleAds = await _eligibleAdsProvider.GetEligibleAdsAsync(
+                request.UserId,
+                request.PlacementType,
+                request.UserContext,
+                cancellationToken);
 
             if (!eligibleAds.Any())
             {
@@ -38,12 +57,17 @@ public class ServeAdQueryHandler : IRequestHandler<ServeAdQuery, ServedAdDto?>
             // Step 3 - Add bids for each eligible ad
             foreach (var ad in eligibleAds)
             {
-                // TODO: Get actual bid amount, CTR prediction, quality score
-                var bidAmount = ad.BidAmount;
-                var predictedCTR = 0.02m; // 2% CTR (mock)
-                var qualityScore = 1.0m;  // Perfect quality (mock)
+                var signals = _auctionScoringService.Score(
+                    ad,
+                    request.PlacementType,
+                    request.UserContext);
 
-                auction.AddBid(ad.AdId, ad.CampaignId, bidAmount, predictedCTR, qualityScore);
+                auction.AddBid(
+                    ad.AdId,
+                    ad.CampaignId,
+                    ad.BidAmount,
+                    signals.PredictedCtr,
+                    signals.QualityScore);
             }
 
             // Step 4 - Run auction
@@ -58,8 +82,33 @@ public class ServeAdQueryHandler : IRequestHandler<ServeAdQuery, ServedAdDto?>
             // Step 5 - Get winning ad details
             var winningAd = eligibleAds.First(a => a.AdId == auction.Result.WinningAdId);
 
-            // TODO: Step 6 - Fire async events (impression tracking, billing)
-            
+            _context.Auctions.Add(auction);
+            _context.Entry(auction).Property("_bidsJson").CurrentValue = JsonSerializer.Serialize(
+                auction.Bids.Select(bid => new
+                {
+                    bid.AdId,
+                    bid.CampaignId,
+                    bid.BidAmount,
+                    bid.PredictedCTR,
+                    bid.QualityScore,
+                    bid.eCPM,
+                }));
+            await _context.SaveEntitiesAsync(cancellationToken);
+
+            await _eventPublisher.PublishAdServedAsync(
+                new AdServedEvent
+                {
+                    AuctionId = auction.Id,
+                    AdId = winningAd.AdId,
+                    CampaignId = winningAd.CampaignId,
+                    UserId = request.UserId,
+                    PlacementType = request.PlacementType,
+                    FinalPrice = auction.Result.FinalPrice,
+                    WinningEcpm = auction.Result.WinningeCPM,
+                    ServedAt = DateTime.UtcNow,
+                },
+                cancellationToken);
+
             var elapsed = (DateTime.UtcNow - startTime).TotalMilliseconds;
             _logger.LogInformation(
                 "Ad served in {Elapsed}ms - AdId: {AdId}, eCPM: {eCPM}, Price: {Price}",
@@ -85,49 +134,4 @@ public class ServeAdQueryHandler : IRequestHandler<ServeAdQuery, ServedAdDto?>
             return null;
         }
     }
-
-    // Mock data for demonstration
-    private List<MockAdData> GetMockEligibleAds(string placementType)
-    {
-        return new List<MockAdData>
-        {
-            new MockAdData
-            {
-                AdId = Guid.NewGuid(),
-                CampaignId = Guid.NewGuid(),
-                BidAmount = 5000, // 5000 VND CPC
-                Format = "single_image",
-                Headline = "Amazing Product - Limited Offer!",
-                PrimaryText = "Get 50% off today only",
-                CallToAction = "Shop Now",
-                CreativeUrl = "https://example.com/creative.jpg",
-                DestinationUrl = "https://example.com/product"
-            },
-            new MockAdData
-            {
-                AdId = Guid.NewGuid(),
-                CampaignId = Guid.NewGuid(),
-                BidAmount = 4500,
-                Format = "single_image",
-                Headline = "Summer Sale",
-                PrimaryText = "Up to 70% discount",
-                CallToAction = "Learn More",
-                CreativeUrl = "https://example.com/creative2.jpg",
-                DestinationUrl = "https://example.com/sale"
-            }
-        };
-    }
-}
-
-internal record MockAdData
-{
-    public Guid AdId { get; init; }
-    public Guid CampaignId { get; init; }
-    public decimal BidAmount { get; init; }
-    public string Format { get; init; } = null!;
-    public string? Headline { get; init; }
-    public string? PrimaryText { get; init; }
-    public string? CallToAction { get; init; }
-    public string? CreativeUrl { get; init; }
-    public string? DestinationUrl { get; init; }
 }
diff --git a/services/ads-serving-service-net/src/AdsServingService.API/Application/Services/AuctionScoringService.cs b/services/ads-serving-service-net/src/AdsServingService.API/Application/Services/AuctionScoringService.cs
new file mode 100644
index 00000000..35ab07a2
--- /dev/null
+++ b/services/ads-serving-service-net/src/AdsServingService.API/Application/Services/AuctionScoringService.cs
@@ -0,0 +1,65 @@
+namespace AdsServingService.API.Application.Services;
+
+/// <summary>
+/// EN: Scoring signal tuple used to place bids in auction.
+/// VI: Bộ tín hiệu scoring dùng để đặt bid trong auction.
+/// </summary>
+public record AuctionBidSignals(decimal PredictedCtr, decimal QualityScore);
+
+/// <summary>
+/// EN: Abstraction for scoring hooks in ad serving auction.
+/// VI: Abstraction cho scoring hook trong auction phục vụ quảng cáo.
+/// </summary>
+public interface IAuctionScoringService
+{
+    AuctionBidSignals Score(
+        EligibleAdCandidate candidate,
+        string placementType,
+        IReadOnlyDictionary<string, string> userContext);
+}
+
+/// <summary>
+/// EN: Default heuristic scoring strategy.
+/// VI: Chiến lược scoring heuristic mặc định.
+/// </summary>
+public class DefaultAuctionScoringService : IAuctionScoringService
+{
+    public AuctionBidSignals Score(
+        EligibleAdCandidate candidate,
+        string placementType,
+        IReadOnlyDictionary<string, string> userContext)
+    {
+        var baseCtr = placementType.ToLowerInvariant() switch
+        {
+            "story" => 0.018m,
+            "banner" => 0.012m,
+            _ => 0.020m,
+        };
+
+        var segmentBoost = 1.0m;
+        if (userContext.TryGetValue("segment", out var segmentValue) &&
+            segmentValue.Equals("high-intent", StringComparison.OrdinalIgnoreCase))
+        {
+            segmentBoost += 0.25m;
+        }
+
+        var recencyBoost = 1.0m;
+        if (userContext.TryGetValue("recentPurchaseDays", out var recencyRaw) &&
+            int.TryParse(recencyRaw, out var recencyDays) &&
+            recencyDays <= 14)
+        {
+            recencyBoost += 0.10m;
+        }
+
+        var predictedCtr = Math.Round(baseCtr * segmentBoost * recencyBoost, 4);
+
+        var qualityScore = candidate.Format.ToLowerInvariant() switch
+        {
+            "single_image" => 1.0m,
+            "video" => 1.1m,
+            _ => 0.95m,
+        };
+
+        return new AuctionBidSignals(predictedCtr, qualityScore);
+    }
+}
diff --git a/services/ads-serving-service-net/src/AdsServingService.API/Application/Services/EligibleAdsProvider.cs b/services/ads-serving-service-net/src/AdsServingService.API/Application/Services/EligibleAdsProvider.cs
new file mode 100644
index 00000000..410ace7c
--- /dev/null
+++ b/services/ads-serving-service-net/src/AdsServingService.API/Application/Services/EligibleAdsProvider.cs
@@ -0,0 +1,89 @@
+namespace AdsServingService.API.Application.Services;
+
+/// <summary>
+/// EN: Candidate ad model used in serving pipeline.
+/// VI: Model quảng cáo ứng viên dùng trong pipeline phục vụ quảng cáo.
+/// </summary>
+public record EligibleAdCandidate
+{
+    public Guid AdId { get; init; }
+    public Guid CampaignId { get; init; }
+    public decimal BidAmount { get; init; }
+    public string Format { get; init; } = null!;
+    public string? Headline { get; init; }
+    public string? PrimaryText { get; init; }
+    public string? CallToAction { get; init; }
+    public string? CreativeUrl { get; init; }
+    public string? DestinationUrl { get; init; }
+}
+
+/// <summary>
+/// EN: Service abstraction to load eligible ads for a serve request.
+/// VI: Abstraction service để tải danh sách quảng cáo đủ điều kiện cho request serve.
+/// </summary>
+public interface IEligibleAdsProvider
+{
+    Task<IReadOnlyList<EligibleAdCandidate>> GetEligibleAdsAsync(
+        Guid userId,
+        string placementType,
+        IReadOnlyDictionary<string, string> userContext,
+        CancellationToken cancellationToken);
+}
+
+/// <summary>
+/// EN: In-memory eligible ads provider used as default fallback.
+/// VI: Provider quảng cáo đủ điều kiện dạng in-memory dùng như fallback mặc định.
+/// </summary>
+public class InMemoryEligibleAdsProvider : IEligibleAdsProvider
+{
+    public Task<IReadOnlyList<EligibleAdCandidate>> GetEligibleAdsAsync(
+        Guid userId,
+        string placementType,
+        IReadOnlyDictionary<string, string> userContext,
+        CancellationToken cancellationToken)
+    {
+        // EN: Keep deterministic IDs per request/user so placement is reproducible.
+        // VI: Giữ ID xác định theo request/user để kết quả placement có thể lặp lại.
+        var hashSeed = Math.Abs(HashCode.Combine(userId, placementType.ToLowerInvariant()));
+        var primaryCampaignId = DeterministicGuid($"{placementType}:{hashSeed}:campaign:primary");
+        var secondaryCampaignId = DeterministicGuid($"{placementType}:{hashSeed}:campaign:secondary");
+
+        IReadOnlyList<EligibleAdCandidate> candidates =
+        [
+            new EligibleAdCandidate
+            {
+                AdId = DeterministicGuid($"{placementType}:{hashSeed}:ad:primary"),
+                CampaignId = primaryCampaignId,
+                BidAmount = 5000m,
+                Format = "single_image",
+                Headline = "Amazing Product - Limited Offer!",
+                PrimaryText = "Get 50% off today only",
+                CallToAction = "Shop Now",
+                CreativeUrl = "https://example.com/creative.jpg",
+                DestinationUrl = "https://example.com/product",
+            },
+            new EligibleAdCandidate
+            {
+                AdId = DeterministicGuid($"{placementType}:{hashSeed}:ad:secondary"),
+                CampaignId = secondaryCampaignId,
+                BidAmount = 4500m,
+                Format = "single_image",
+                Headline = "Summer Sale",
+                PrimaryText = "Up to 70% discount",
+                CallToAction = "Learn More",
+                CreativeUrl = "https://example.com/creative2.jpg",
+                DestinationUrl = "https://example.com/sale",
+            },
+        ];
+
+        return Task.FromResult(candidates);
+    }
+
+    private static Guid DeterministicGuid(string input)
+    {
+        var bytes = System.Security.Cryptography.SHA256.HashData(System.Text.Encoding.UTF8.GetBytes(input));
+        var guidBytes = new byte[16];
+        Array.Copy(bytes, guidBytes, guidBytes.Length);
+        return new Guid(guidBytes);
+    }
+}
diff --git a/services/ads-serving-service-net/src/AdsServingService.API/Controllers/AdminAuctionsController.cs b/services/ads-serving-service-net/src/AdsServingService.API/Controllers/AdminAuctionsController.cs
index 2bf41c21..acd89c58 100644
--- a/services/ads-serving-service-net/src/AdsServingService.API/Controllers/AdminAuctionsController.cs
+++ b/services/ads-serving-service-net/src/AdsServingService.API/Controllers/AdminAuctionsController.cs
@@ -56,25 +56,10 @@ public class AdminAuctionsController : ControllerBase
     /// </summary>
     [HttpGet("statistics")]
     [ProducesResponseType(typeof(AuctionStatisticsDto), StatusCodes.Status200OK)]
-    public ActionResult<AuctionStatisticsDto> GetStatistics()
+    public async Task<ActionResult<AuctionStatisticsDto>> GetStatistics()
     {
-        // TODO: Implement statistics query handler
         _logger.LogInformation("Auction statistics requested");
-        
-        return Ok(new AuctionStatisticsDto
-        {
-            TotalAuctions = 0,
-            AverageWinRate = 0,
-            AverageeCPM = 0,
-            TotalBidsPlaced = 0
-        });
+        var statistics = await _mediator.Send(new GetAuctionStatisticsQuery());
+        return Ok(statistics);
     }
 }
-
-public record AuctionStatisticsDto
-{
-    public int TotalAuctions { get; init; }
-    public decimal AverageWinRate { get; init; }
-    public decimal AverageeCPM { get; init; }
-    public long TotalBidsPlaced { get; init; }
-}
diff --git a/services/ads-serving-service-net/src/AdsServingService.API/Controllers/AdsController.cs b/services/ads-serving-service-net/src/AdsServingService.API/Controllers/AdsController.cs
index 2fb2bc31..ce7e2777 100644
--- a/services/ads-serving-service-net/src/AdsServingService.API/Controllers/AdsController.cs
+++ b/services/ads-serving-service-net/src/AdsServingService.API/Controllers/AdsController.cs
@@ -1,4 +1,5 @@
 using AdsServingService.API.Application.Queries;
+using AdsServingService.API.Application.Events;
 using MediatR;
 using Microsoft.AspNetCore.Mvc;
 
@@ -14,11 +15,16 @@ namespace AdsServingService.API.Controllers;
 public class AdsController : ControllerBase
 {
     private readonly IMediator _mediator;
+    private readonly IAdServingEventPublisher _eventPublisher;
     private readonly ILogger<AdsController> _logger;
 
-    public AdsController(IMediator mediator, ILogger<AdsController> logger)
+    public AdsController(
+        IMediator mediator,
+        IAdServingEventPublisher eventPublisher,
+        ILogger<AdsController> logger)
     {
         _mediator = mediator ?? throw new ArgumentNullException(nameof(mediator));
+        _eventPublisher = eventPublisher ?? throw new ArgumentNullException(nameof(eventPublisher));
         _logger = logger ?? throw new ArgumentNullException(nameof(logger));
     }
 
@@ -52,14 +58,18 @@ public class AdsController : ControllerBase
     /// </summary>
     [HttpPost("events/impression")]
     [ProducesResponseType(StatusCodes.Status202Accepted)]
-    public IActionResult TrackImpression([FromBody] ImpressionEvent impressionEvent)
+    public async Task<IActionResult> TrackImpression([FromBody] ImpressionEvent impressionEvent)
     {
         _logger.LogInformation("Impression tracked for Ad {AdId}", impressionEvent.AdId);
-        
-        // TODO: Publish to RabbitMQ for async processing
-        // - ads-billing (charge advertiser)
-        // - ads-tracking (attribution)
-        // - ads-analytics (metrics)
+
+        await _eventPublisher.PublishImpressionTrackedAsync(
+            new AdImpressionTrackedEvent
+            {
+                AdId = impressionEvent.AdId,
+                UserId = impressionEvent.UserId,
+                Timestamp = impressionEvent.Timestamp,
+            },
+            HttpContext.RequestAborted);
 
         return Accepted();
     }
@@ -70,11 +80,18 @@ public class AdsController : ControllerBase
     /// </summary>
     [HttpPost("events/click")]
     [ProducesResponseType(StatusCodes.Status202Accepted)]
-    public IActionResult TrackClick([FromBody] ClickEvent clickEvent)
+    public async Task<IActionResult> TrackClick([FromBody] ClickEvent clickEvent)
     {
         _logger.LogInformation("Click tracked for Ad {AdId}", clickEvent.AdId);
-        
-        // TODO: Publish to RabbitMQ for async processing
+
+        await _eventPublisher.PublishClickTrackedAsync(
+            new AdClickTrackedEvent
+            {
+                AdId = clickEvent.AdId,
+                UserId = clickEvent.UserId,
+                Timestamp = clickEvent.Timestamp,
+            },
+            HttpContext.RequestAborted);
 
         return Accepted();
     }
diff --git a/services/ads-serving-service-net/src/AdsServingService.API/Program.cs b/services/ads-serving-service-net/src/AdsServingService.API/Program.cs
index e6e5ed9d..f788dadb 100644
--- a/services/ads-serving-service-net/src/AdsServingService.API/Program.cs
+++ b/services/ads-serving-service-net/src/AdsServingService.API/Program.cs
@@ -1,4 +1,6 @@
 using Asp.Versioning;
+using AdsServingService.API.Application.Events;
+using AdsServingService.API.Application.Services;
 using FluentValidation;
 using Hellang.Middleware.ProblemDetails;
 using AdsServingService.API.Application.Behaviors;
@@ -25,6 +27,9 @@ try
 
     // EN: Add Infrastructure services / VI: Thêm Infrastructure services
     builder.Services.AddInfrastructure(builder.Configuration);
+    builder.Services.AddScoped<IEligibleAdsProvider, InMemoryEligibleAdsProvider>();
+    builder.Services.AddScoped<IAuctionScoringService, DefaultAuctionScoringService>();
+    builder.Services.AddScoped<IAdServingEventPublisher, LoggingAdServingEventPublisher>();
 
     // EN: Add MediatR with behaviors / VI: Thêm MediatR với behaviors
     builder.Services.AddMediatR(cfg =>