interim commit

src/StellaOps.Feedser.Exporter.Json/JsonFeedExporter.cs

@@ -71,6 +71,17 @@ public sealed class JsonFeedExporter : IFeedExporter
             return;
         }
 
+        var resetBaseline = existingState is null
+            || string.IsNullOrWhiteSpace(existingState.BaseExportId)
+            || string.IsNullOrWhiteSpace(existingState.BaseDigest);
+
+        if (existingState is not null
+            && !string.IsNullOrWhiteSpace(_options.TargetRepository)
+            && !string.Equals(existingState.TargetRepository, _options.TargetRepository, StringComparison.Ordinal))
+        {
+            resetBaseline = true;
+        }
+
         await _stateManager.StoreFullExportAsync(
             ExporterId,
             exportId,
@@ -78,6 +89,7 @@ public sealed class JsonFeedExporter : IFeedExporter
             cursor: digest,
             targetRepository: _options.TargetRepository,
             exporterVersion: _exporterVersion,
+            resetBaseline: resetBaseline,
             cancellationToken: cancellationToken).ConfigureAwait(false);
 
         await JsonExportManifestWriter.WriteAsync(result, digest, _exporterVersion, cancellationToken).ConfigureAwait(false);

src/StellaOps.Feedser.Exporter.TrivyDb.Tests/TrivyDbExportPlannerTests.cs

@@ -16,6 +16,7 @@ public sealed class TrivyDbExportPlannerTests
         Assert.Equal("sha256:abcd", plan.TreeDigest);
         Assert.Null(plan.BaseExportId);
         Assert.Null(plan.BaseManifestDigest);
+        Assert.True(plan.ResetBaseline);
     }
 
     [Fact]
@@ -39,6 +40,7 @@ public sealed class TrivyDbExportPlannerTests
         Assert.Equal("sha256:unchanged", plan.TreeDigest);
         Assert.Equal("20240810T000000Z", plan.BaseExportId);
         Assert.Equal("sha256:base", plan.BaseManifestDigest);
+        Assert.False(plan.ResetBaseline);
     }
 
     [Fact]
@@ -62,5 +64,12 @@ public sealed class TrivyDbExportPlannerTests
         Assert.Equal("sha256:new", plan.TreeDigest);
         Assert.Equal("20240810T000000Z", plan.BaseExportId);
         Assert.Equal("sha256:base", plan.BaseManifestDigest);
+        Assert.False(plan.ResetBaseline);
+
+        var deltaState = state with { LastDeltaDigest = "sha256:delta" };
+        var deltaPlan = planner.CreatePlan(deltaState, "sha256:newer");
+
+        Assert.Equal(TrivyDbExportMode.Full, deltaPlan.Mode);
+        Assert.True(deltaPlan.ResetBaseline);
     }
 }

src/StellaOps.Feedser.Exporter.TrivyDb.Tests/TrivyDbFeedExporterTests.cs

@@ -281,6 +281,77 @@ public sealed class TrivyDbFeedExporterTests : IDisposable
         Assert.Empty(orasPusher.Pushes);
     }
 
+    [Fact]
+    public async Task ExportAsync_ResetsBaselineWhenDeltaChainExists()
+    {
+        var advisory = CreateSampleAdvisory("CVE-2024-5000", "Baseline reset");
+        var advisoryStore = new StubAdvisoryStore(advisory);
+
+        var optionsValue = new TrivyDbExportOptions
+        {
+            OutputRoot = _root,
+            ReferencePrefix = "example/trivy",
+            Json = new JsonExportOptions
+            {
+                OutputRoot = _jsonRoot,
+                MaintainLatestSymlink = false,
+            },
+            KeepWorkingTree = false,
+            TargetRepository = "registry.example/trivy",
+        };
+
+        var options = Options.Create(optionsValue);
+        var packageBuilder = new TrivyDbPackageBuilder();
+        var ociWriter = new TrivyDbOciWriter();
+        var planner = new TrivyDbExportPlanner();
+        var stateStore = new InMemoryExportStateStore();
+        var timeProvider = new TestTimeProvider(DateTimeOffset.Parse("2024-09-22T00:00:00Z", CultureInfo.InvariantCulture));
+        var existingRecord = new ExportStateRecord(
+            TrivyDbFeedExporter.ExporterId,
+            BaseExportId: "20240919T120000Z",
+            BaseDigest: "sha256:base",
+            LastFullDigest: "sha256:base",
+            LastDeltaDigest: "sha256:delta",
+            ExportCursor: "sha256:old",
+            TargetRepository: "registry.example/trivy",
+            ExporterVersion: "0.9.0",
+            UpdatedAt: timeProvider.GetUtcNow().AddMinutes(-30));
+        await stateStore.UpsertAsync(existingRecord, CancellationToken.None);
+
+        var stateManager = new ExportStateManager(stateStore, timeProvider);
+        var builderMetadata = JsonSerializer.SerializeToUtf8Bytes(new
+        {
+            Version = 2,
+            NextUpdate = "2024-09-23T00:00:00Z",
+            UpdatedAt = "2024-09-22T00:00:00Z",
+        });
+        var builder = new StubTrivyDbBuilder(_root, builderMetadata);
+        var orasPusher = new StubTrivyDbOrasPusher();
+        var exporter = new TrivyDbFeedExporter(
+            advisoryStore,
+            new VulnListJsonExportPathResolver(),
+            options,
+            packageBuilder,
+            ociWriter,
+            stateManager,
+            planner,
+            builder,
+            orasPusher,
+            NullLogger<TrivyDbFeedExporter>.Instance,
+            timeProvider);
+
+        using var provider = new ServiceCollection().BuildServiceProvider();
+        await exporter.ExportAsync(provider, CancellationToken.None);
+
+        var updated = await stateStore.FindAsync(TrivyDbFeedExporter.ExporterId, CancellationToken.None);
+        Assert.NotNull(updated);
+        Assert.Equal("20240922T000000Z", updated!.BaseExportId);
+        Assert.Equal(updated.BaseDigest, updated.LastFullDigest);
+        Assert.Null(updated.LastDeltaDigest);
+        Assert.NotEqual("sha256:old", updated.ExportCursor);
+        Assert.Equal("registry.example/trivy", updated.TargetRepository);
+    }
+
     private static Advisory CreateSampleAdvisory(
         string advisoryKey = "CVE-2024-9999",
         string title = "Trivy Export Test")

src/StellaOps.Feedser.Exporter.TrivyDb/TASKS.md

@@ -8,6 +8,6 @@
 |Offline bundle toggle|BE-Export|Exporters|DONE – Deterministic OCI layout bundle emitted when enabled.|
 |Deterministic ordering of advisories|BE-Export|Models|DONE – exporter now loads advisories, sorts by advisoryKey, and emits sorted JSON trees with deterministic OCI payloads.|
 |End-to-end tests with small dataset|QA|Exporters|DONE – added deterministic round-trip test covering OCI layout, media types, and digest stability w/ repeated inputs.|
-|ExportState persistence & idempotence|BE-Export|Storage.Mongo|DOING – `ExportStateManager` keeps stable base export metadata; delta reset remains pending.|
+|ExportState persistence & idempotence|BE-Export|Storage.Mongo|DONE – baseline resets wired into `ExportStateManager`, planner signals resets after delta runs, and exporters update state w/ repository-aware baseline rotation + tests.|
 |Streamed package building to avoid large copies|BE-Export|Exporters|DONE – metadata/config now reuse backing arrays and OCI writer streams directly without double buffering.|
 |Plan incremental/delta exports|BE-Export|Exporters|TODO – design reuse of existing blobs/layers when inputs unchanged instead of rewriting full trees each run.|

src/StellaOps.Feedser.Exporter.TrivyDb/TrivyDbExportPlan.cs

@@ -4,4 +4,5 @@ public sealed record TrivyDbExportPlan(
     TrivyDbExportMode Mode,
     string TreeDigest,
     string? BaseExportId,
-    string? BaseManifestDigest);
+    string? BaseManifestDigest,
+    bool ResetBaseline);

src/StellaOps.Feedser.Exporter.TrivyDb/TrivyDbExportPlanner.cs

@@ -11,7 +11,12 @@ public sealed class TrivyDbExportPlanner
 
         if (existingState is null)
         {
-            return new TrivyDbExportPlan(TrivyDbExportMode.Full, treeDigest, BaseExportId: null, BaseManifestDigest: null);
+            return new TrivyDbExportPlan(
+                TrivyDbExportMode.Full,
+                treeDigest,
+                BaseExportId: null,
+                BaseManifestDigest: null,
+                ResetBaseline: true);
         }
 
         if (string.Equals(existingState.ExportCursor, treeDigest, StringComparison.Ordinal))
@@ -20,14 +25,18 @@ public sealed class TrivyDbExportPlanner
                 TrivyDbExportMode.Skip,
                 treeDigest,
                 existingState.BaseExportId,
-                existingState.LastFullDigest);
+                existingState.LastFullDigest,
+                ResetBaseline: false);
         }
 
+        var resetBaseline = existingState.LastDeltaDigest is not null;
+
         // Placeholder for future delta support – current behavior always rebuilds when tree changes.
         return new TrivyDbExportPlan(
             TrivyDbExportMode.Full,
             treeDigest,
             existingState.BaseExportId,
-            existingState.LastFullDigest);
+            existingState.LastFullDigest,
+            resetBaseline);
     }
 }

src/StellaOps.Feedser.Exporter.TrivyDb/TrivyDbFeedExporter.cs

@@ -130,6 +130,18 @@ public sealed class TrivyDbFeedExporter : IFeedExporter
                 exportId,
                 ociResult.ManifestDigest);
 
+            var resetBaseline = plan.ResetBaseline
+                || existingState is null
+                || string.IsNullOrWhiteSpace(existingState.BaseExportId)
+                || string.IsNullOrWhiteSpace(existingState.BaseDigest);
+
+            if (existingState is not null
+                && !string.IsNullOrWhiteSpace(_options.TargetRepository)
+                && !string.Equals(existingState.TargetRepository, _options.TargetRepository, StringComparison.Ordinal))
+            {
+                resetBaseline = true;
+            }
+
             await _stateManager.StoreFullExportAsync(
                 ExporterId,
                 exportId,
@@ -137,6 +149,7 @@ public sealed class TrivyDbFeedExporter : IFeedExporter
                 cursor: treeDigest,
                 targetRepository: _options.TargetRepository,
                 exporterVersion: _exporterVersion,
+                resetBaseline: resetBaseline,
                 cancellationToken: cancellationToken).ConfigureAwait(false);
 
             await CreateOfflineBundleAsync(destination, exportId, exportedAt, cancellationToken).ConfigureAwait(false);

src/StellaOps.Feedser.Merge.Tests/AdvisoryIdentityResolverTests.cs

@@ -0,0 +1,91 @@
+using System;
+using System.Linq;
+using StellaOps.Feedser.Merge.Identity;
+using StellaOps.Feedser.Models;
+using Xunit;
+
+namespace StellaOps.Feedser.Merge.Tests;
+
+public sealed class AdvisoryIdentityResolverTests
+{
+    private readonly AdvisoryIdentityResolver _resolver = new();
+
+    [Fact]
+    public void Resolve_GroupsBySharedCveAlias()
+    {
+        var nvd = CreateAdvisory("CVE-2025-1234", aliases: new[] { "CVE-2025-1234" }, source: "nvd");
+        var vendor = CreateAdvisory("VSA-2025-01", aliases: new[] { "CVE-2025-1234", "VSA-2025-01" }, source: "vendor");
+
+        var clusters = _resolver.Resolve(new[] { nvd, vendor });
+
+        var cluster = Assert.Single(clusters);
+        Assert.Equal("CVE-2025-1234", cluster.AdvisoryKey);
+        Assert.Equal(2, cluster.Advisories.Length);
+        Assert.True(cluster.Aliases.Any(alias => alias.Value == "CVE-2025-1234"));
+    }
+
+    [Fact]
+    public void Resolve_PrefersPsirtAliasWhenNoCve()
+    {
+        var vendor = CreateAdvisory("VMSA-2025-0001", aliases: new[] { "VMSA-2025-0001" }, source: "vmware");
+        var osv = CreateAdvisory("OSV-2025-1", aliases: new[] { "OSV-2025-1", "GHSA-xxxx-yyyy-zzzz", "VMSA-2025-0001" }, source: "osv");
+
+        var clusters = _resolver.Resolve(new[] { vendor, osv });
+
+        var cluster = Assert.Single(clusters);
+        Assert.Equal("VMSA-2025-0001", cluster.AdvisoryKey);
+        Assert.Equal(2, cluster.Advisories.Length);
+        Assert.True(cluster.Aliases.Any(alias => alias.Value == "VMSA-2025-0001"));
+    }
+
+    [Fact]
+    public void Resolve_FallsBackToGhsaWhenOnlyGhsaPresent()
+    {
+        var ghsa = CreateAdvisory("GHSA-aaaa-bbbb-cccc", aliases: new[] { "GHSA-aaaa-bbbb-cccc" }, source: "ghsa");
+        var osv = CreateAdvisory("OSV-2025-99", aliases: new[] { "OSV-2025-99", "GHSA-aaaa-bbbb-cccc" }, source: "osv");
+
+        var clusters = _resolver.Resolve(new[] { ghsa, osv });
+
+        var cluster = Assert.Single(clusters);
+        Assert.Equal("GHSA-aaaa-bbbb-cccc", cluster.AdvisoryKey);
+        Assert.Equal(2, cluster.Advisories.Length);
+        Assert.True(cluster.Aliases.Any(alias => alias.Value == "GHSA-aaaa-bbbb-cccc"));
+    }
+
+    [Fact]
+    public void Resolve_GroupsByKeyWhenNoAliases()
+    {
+        var first = CreateAdvisory("custom-1", aliases: Array.Empty<string>(), source: "source-a");
+        var second = CreateAdvisory("custom-1", aliases: Array.Empty<string>(), source: "source-b");
+
+        var clusters = _resolver.Resolve(new[] { first, second });
+
+        var cluster = Assert.Single(clusters);
+        Assert.Equal("custom-1", cluster.AdvisoryKey);
+        Assert.Equal(2, cluster.Advisories.Length);
+        Assert.Contains(cluster.Aliases, alias => alias.Value == "custom-1");
+    }
+
+    private static Advisory CreateAdvisory(string key, string[] aliases, string source)
+    {
+        var provenance = new[]
+        {
+            new AdvisoryProvenance(source, "mapping", key, DateTimeOffset.UtcNow),
+        };
+
+        return new Advisory(
+            key,
+            $"{key} title",
+            $"{key} summary",
+            "en",
+            DateTimeOffset.UtcNow,
+            DateTimeOffset.UtcNow,
+            null,
+            exploitKnown: false,
+            aliases,
+            Array.Empty<AdvisoryReference>(),
+            Array.Empty<AffectedPackage>(),
+            Array.Empty<CvssMetric>(),
+            provenance);
+    }
+}

src/StellaOps.Feedser.Merge/Identity/AdvisoryIdentityCluster.cs

@@ -0,0 +1,56 @@
+using System;
+using System.Collections.Generic;
+using System.Collections.Immutable;
+using System.Linq;
+using StellaOps.Feedser.Models;
+
+namespace StellaOps.Feedser.Merge.Identity;
+
+/// <summary>
+/// Represents a connected component of advisories that refer to the same vulnerability.
+/// </summary>
+public sealed class AdvisoryIdentityCluster
+{
+    public AdvisoryIdentityCluster(string advisoryKey, IEnumerable<Advisory> advisories, IEnumerable<AliasIdentity> aliases)
+    {
+        AdvisoryKey = !string.IsNullOrWhiteSpace(advisoryKey)
+            ? advisoryKey.Trim()
+            : throw new ArgumentException("Canonical advisory key must be provided.", nameof(advisoryKey));
+
+        var advisoriesArray = (advisories ?? throw new ArgumentNullException(nameof(advisories)))
+            .Where(static advisory => advisory is not null)
+            .OrderBy(static advisory => advisory.AdvisoryKey, StringComparer.OrdinalIgnoreCase)
+            .ThenBy(static advisory => advisory.Provenance.Length)
+            .ThenBy(static advisory => advisory.Title, StringComparer.OrdinalIgnoreCase)
+            .ToImmutableArray();
+
+        if (advisoriesArray.IsDefaultOrEmpty)
+        {
+            throw new ArgumentException("At least one advisory is required for a cluster.", nameof(advisories));
+        }
+
+        var aliasArray = (aliases ?? throw new ArgumentNullException(nameof(aliases)))
+            .Where(static alias => alias is not null && !string.IsNullOrWhiteSpace(alias.Value))
+            .GroupBy(static alias => alias.Value, StringComparer.OrdinalIgnoreCase)
+            .Select(static group =>
+            {
+                var representative = group
+                    .OrderBy(static entry => entry.Scheme ?? string.Empty, StringComparer.OrdinalIgnoreCase)
+                    .ThenBy(static entry => entry.Value, StringComparer.OrdinalIgnoreCase)
+                    .First();
+                return representative;
+            })
+            .OrderBy(static alias => alias.Scheme ?? string.Empty, StringComparer.OrdinalIgnoreCase)
+            .ThenBy(static alias => alias.Value, StringComparer.OrdinalIgnoreCase)
+            .ToImmutableArray();
+
+        Advisories = advisoriesArray;
+        Aliases = aliasArray;
+    }
+
+    public string AdvisoryKey { get; }
+
+    public ImmutableArray<Advisory> Advisories { get; }
+
+    public ImmutableArray<AliasIdentity> Aliases { get; }
+}

src/StellaOps.Feedser.Merge/Identity/AdvisoryIdentityResolver.cs

@@ -0,0 +1,303 @@
+using System;
+using System.Collections.Generic;
+using System.Collections.Immutable;
+using System.Linq;
+using System.Runtime.CompilerServices;
+using StellaOps.Feedser.Models;
+
+namespace StellaOps.Feedser.Merge.Identity;
+
+/// <summary>
+/// Builds an alias-driven identity graph that groups advisories referring to the same vulnerability.
+/// </summary>
+public sealed class AdvisoryIdentityResolver
+{
+    private static readonly string[] CanonicalAliasPriority =
+    {
+        AliasSchemes.Cve,
+        AliasSchemes.Rhsa,
+        AliasSchemes.Usn,
+        AliasSchemes.Dsa,
+        AliasSchemes.SuseSu,
+        AliasSchemes.Msrc,
+        AliasSchemes.CiscoSa,
+        AliasSchemes.OracleCpu,
+        AliasSchemes.Vmsa,
+        AliasSchemes.Apsb,
+        AliasSchemes.Apa,
+        AliasSchemes.AppleHt,
+        AliasSchemes.ChromiumPost,
+        AliasSchemes.Icsa,
+        AliasSchemes.Jvndb,
+        AliasSchemes.Jvn,
+        AliasSchemes.Bdu,
+        AliasSchemes.Vu,
+        AliasSchemes.Ghsa,
+        AliasSchemes.OsV,
+    };
+
+    /// <summary>
+    /// Groups the provided advisories into identity clusters using normalized aliases.
+    /// </summary>
+    public IReadOnlyList<AdvisoryIdentityCluster> Resolve(IEnumerable<Advisory> advisories)
+    {
+        ArgumentNullException.ThrowIfNull(advisories);
+
+        var materialized = advisories
+            .Where(static advisory => advisory is not null)
+            .Distinct()
+            .ToArray();
+
+        if (materialized.Length == 0)
+        {
+            return Array.Empty<AdvisoryIdentityCluster>();
+        }
+
+        var aliasIndex = BuildAliasIndex(materialized);
+        var visited = new HashSet<Advisory>();
+        var clusters = new List<AdvisoryIdentityCluster>();
+
+        foreach (var advisory in materialized)
+        {
+            if (!visited.Add(advisory))
+            {
+                continue;
+            }
+
+            var component = TraverseComponent(advisory, visited, aliasIndex);
+            var key = DetermineCanonicalKey(component);
+            var aliases = component
+                .SelectMany(static entry => entry.Aliases)
+                .Select(static alias => new AliasIdentity(alias.Normalized, alias.Scheme));
+            clusters.Add(new AdvisoryIdentityCluster(key, component.Select(static entry => entry.Advisory), aliases));
+        }
+
+        return clusters
+            .OrderBy(static cluster => cluster.AdvisoryKey, StringComparer.OrdinalIgnoreCase)
+            .ToImmutableArray();
+    }
+
+    private static Dictionary<string, List<AdvisoryAliasEntry>> BuildAliasIndex(IEnumerable<Advisory> advisories)
+    {
+        var index = new Dictionary<string, List<AdvisoryAliasEntry>>(StringComparer.OrdinalIgnoreCase);
+
+        foreach (var advisory in advisories)
+        {
+            foreach (var alias in ExtractAliases(advisory))
+            {
+                if (!index.TryGetValue(alias.Normalized, out var list))
+                {
+                    list = new List<AdvisoryAliasEntry>();
+                    index[alias.Normalized] = list;
+                }
+
+                list.Add(new AdvisoryAliasEntry(advisory, alias.Normalized, alias.Scheme));
+            }
+        }
+
+        return index;
+    }
+
+    private static IReadOnlyList<AliasBinding> TraverseComponent(
+        Advisory root,
+        HashSet<Advisory> visited,
+        Dictionary<string, List<AdvisoryAliasEntry>> aliasIndex)
+    {
+        var stack = new Stack<Advisory>();
+        stack.Push(root);
+
+        var bindings = new Dictionary<Advisory, AliasBinding>(ReferenceEqualityComparer<Advisory>.Instance);
+
+        while (stack.Count > 0)
+        {
+            var advisory = stack.Pop();
+
+            if (!bindings.TryGetValue(advisory, out var binding))
+            {
+                binding = new AliasBinding(advisory);
+                bindings[advisory] = binding;
+            }
+
+            foreach (var alias in ExtractAliases(advisory))
+            {
+                binding.AddAlias(alias.Normalized, alias.Scheme);
+
+                if (!aliasIndex.TryGetValue(alias.Normalized, out var neighbors))
+                {
+                    continue;
+                }
+
+                foreach (var neighbor in neighbors.Select(static entry => entry.Advisory))
+                {
+                    if (visited.Add(neighbor))
+                    {
+                        stack.Push(neighbor);
+                    }
+
+                    if (!bindings.TryGetValue(neighbor, out var neighborBinding))
+                    {
+                        neighborBinding = new AliasBinding(neighbor);
+                        bindings[neighbor] = neighborBinding;
+                    }
+
+                    neighborBinding.AddAlias(alias.Normalized, alias.Scheme);
+                }
+            }
+        }
+
+        return bindings.Values
+            .OrderBy(static binding => binding.Advisory.AdvisoryKey, StringComparer.OrdinalIgnoreCase)
+            .ToImmutableArray();
+    }
+
+    private static string DetermineCanonicalKey(IReadOnlyList<AliasBinding> component)
+    {
+        var aliases = component
+            .SelectMany(static binding => binding.Aliases)
+            .Where(static alias => !string.IsNullOrWhiteSpace(alias.Normalized))
+            .ToArray();
+
+        foreach (var scheme in CanonicalAliasPriority)
+        {
+            var candidate = aliases
+                .Where(alias => string.Equals(alias.Scheme, scheme, StringComparison.OrdinalIgnoreCase))
+                .Select(static alias => alias.Normalized)
+                .OrderBy(static alias => alias, StringComparer.OrdinalIgnoreCase)
+                .FirstOrDefault();
+
+            if (candidate is not null)
+            {
+                return candidate;
+            }
+        }
+
+        var fallbackAlias = aliases
+            .Select(static alias => alias.Normalized)
+            .OrderBy(static alias => alias, StringComparer.OrdinalIgnoreCase)
+            .FirstOrDefault();
+
+        if (!string.IsNullOrWhiteSpace(fallbackAlias))
+        {
+            return fallbackAlias;
+        }
+
+        var advisoryKey = component
+            .Select(static binding => binding.Advisory.AdvisoryKey)
+            .Where(static value => !string.IsNullOrWhiteSpace(value))
+            .OrderBy(static value => value, StringComparer.OrdinalIgnoreCase)
+            .FirstOrDefault();
+
+        if (!string.IsNullOrWhiteSpace(advisoryKey))
+        {
+            return advisoryKey.Trim();
+        }
+
+        throw new InvalidOperationException("Unable to determine canonical advisory key for cluster.");
+    }
+
+    private static IEnumerable<AliasProjection> ExtractAliases(Advisory advisory)
+    {
+        var seen = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
+
+        foreach (var candidate in EnumerateAliasCandidates(advisory))
+        {
+            if (string.IsNullOrWhiteSpace(candidate))
+            {
+                continue;
+            }
+
+            var trimmed = candidate.Trim();
+            if (!seen.Add(trimmed))
+            {
+                continue;
+            }
+
+            if (AliasSchemeRegistry.TryNormalize(trimmed, out var normalized, out var scheme) &&
+                !string.IsNullOrWhiteSpace(normalized))
+            {
+                yield return new AliasProjection(normalized.Trim(), string.IsNullOrWhiteSpace(scheme) ? null : scheme);
+            }
+            else if (!string.IsNullOrWhiteSpace(normalized))
+            {
+                yield return new AliasProjection(normalized.Trim(), null);
+            }
+        }
+    }
+
+    private static IEnumerable<string> EnumerateAliasCandidates(Advisory advisory)
+    {
+        if (!string.IsNullOrWhiteSpace(advisory.AdvisoryKey))
+        {
+            yield return advisory.AdvisoryKey;
+        }
+
+        if (!advisory.Aliases.IsDefaultOrEmpty)
+        {
+            foreach (var alias in advisory.Aliases)
+            {
+                if (!string.IsNullOrWhiteSpace(alias))
+                {
+                    yield return alias;
+                }
+            }
+        }
+    }
+
+    private readonly record struct AdvisoryAliasEntry(Advisory Advisory, string Normalized, string? Scheme);
+
+    private readonly record struct AliasProjection(string Normalized, string? Scheme);
+
+    private sealed class AliasBinding
+    {
+        private readonly HashSet<AliasProjection> _aliases = new(HashSetAliasComparer.Instance);
+
+        public AliasBinding(Advisory advisory)
+        {
+            Advisory = advisory ?? throw new ArgumentNullException(nameof(advisory));
+        }
+
+        public Advisory Advisory { get; }
+
+        public IReadOnlyCollection<AliasProjection> Aliases => _aliases;
+
+        public void AddAlias(string normalized, string? scheme)
+        {
+            if (string.IsNullOrWhiteSpace(normalized))
+            {
+                return;
+            }
+
+            _aliases.Add(new AliasProjection(normalized.Trim(), scheme is null ? null : scheme.Trim()));
+        }
+    }
+
+    private sealed class HashSetAliasComparer : IEqualityComparer<AliasProjection>
+    {
+        public static readonly HashSetAliasComparer Instance = new();
+
+        public bool Equals(AliasProjection x, AliasProjection y)
+            => string.Equals(x.Normalized, y.Normalized, StringComparison.OrdinalIgnoreCase)
+               && string.Equals(x.Scheme, y.Scheme, StringComparison.OrdinalIgnoreCase);
+
+        public int GetHashCode(AliasProjection obj)
+        {
+            var hash = StringComparer.OrdinalIgnoreCase.GetHashCode(obj.Normalized);
+            if (!string.IsNullOrWhiteSpace(obj.Scheme))
+            {
+                hash = HashCode.Combine(hash, StringComparer.OrdinalIgnoreCase.GetHashCode(obj.Scheme));
+            }
+
+            return hash;
+        }
+    }
+
+    private sealed class ReferenceEqualityComparer<T> : IEqualityComparer<T>
+        where T : class
+    {
+        public static readonly ReferenceEqualityComparer<T> Instance = new();
+
+        public bool Equals(T? x, T? y) => ReferenceEquals(x, y);
+
+        public int GetHashCode(T obj) => RuntimeHelpers.GetHashCode(obj);
+    }
+}

src/StellaOps.Feedser.Merge/Identity/AliasIdentity.cs

@@ -0,0 +1,24 @@
+using System;
+
+namespace StellaOps.Feedser.Merge.Identity;
+
+/// <summary>
+/// Normalized alias representation used within identity clusters.
+/// </summary>
+public sealed class AliasIdentity
+{
+    public AliasIdentity(string value, string? scheme)
+    {
+        if (string.IsNullOrWhiteSpace(value))
+        {
+            throw new ArgumentException("Alias value must be provided.", nameof(value));
+        }
+
+        Value = value.Trim();
+        Scheme = string.IsNullOrWhiteSpace(scheme) ? null : scheme.Trim();
+    }
+
+    public string Value { get; }
+
+    public string? Scheme { get; }
+}

src/StellaOps.Feedser.Merge/TASKS.md

@@ -1,7 +1,7 @@
 # TASKS
 | Task | Owner(s) | Depends on | Notes |
 |---|---|---|---|
-|Identity graph and alias resolver|BE-Merge|Models, Storage.Mongo|Deterministic key choice; cycle-safe.|
+|Identity graph and alias resolver|BE-Merge|Models, Storage.Mongo|DONE – `AdvisoryIdentityResolver` builds alias-driven clusters with canonical key selection + unit coverage.|
 |Precedence policy engine|BE-Merge|Architecture|PSIRT/OVAL > NVD; CERTs enrich; KEV flag.|
 |NEVRA comparer plus tests|BE-Merge (Distro WG)|Source.Distro fixtures|DONE – Added Nevra parser/comparer with tilde-aware rpm ordering and unit coverage.|
 |Debian EVR comparer plus tests|BE-Merge (Distro WG)|Debian fixtures|DONE – DebianEvr comparer mirrors dpkg ordering with tilde/epoch handling and unit coverage.|

src/StellaOps.Feedser.Models.Tests/AffectedPackageStatusTests.cs

@@ -10,6 +10,15 @@ public sealed class AffectedPackageStatusTests
     [InlineData("KNOWN-NOT-AFFECTED", AffectedPackageStatusCatalog.KnownNotAffected)]
     [InlineData("Under Investigation", AffectedPackageStatusCatalog.UnderInvestigation)]
     [InlineData("Fixed", AffectedPackageStatusCatalog.Fixed)]
+    [InlineData("Known not vulnerable", AffectedPackageStatusCatalog.KnownNotAffected)]
+    [InlineData("Impacted", AffectedPackageStatusCatalog.Affected)]
+    [InlineData("Not Vulnerable", AffectedPackageStatusCatalog.NotAffected)]
+    [InlineData("Analysis in progress", AffectedPackageStatusCatalog.UnderInvestigation)]
+    [InlineData("Patch Available", AffectedPackageStatusCatalog.Fixed)]
+    [InlineData("Workaround available", AffectedPackageStatusCatalog.Mitigated)]
+    [InlineData("Does Not Apply", AffectedPackageStatusCatalog.NotApplicable)]
+    [InlineData("Awaiting fix", AffectedPackageStatusCatalog.Pending)]
+    [InlineData("TBD", AffectedPackageStatusCatalog.Unknown)]
     public void Constructor_NormalizesStatus(string input, string expected)
     {
         var provenance = new AdvisoryProvenance("test", "status", "value", DateTimeOffset.UtcNow);
@@ -25,4 +34,42 @@ public sealed class AffectedPackageStatusTests
         var provenance = new AdvisoryProvenance("test", "status", "value", DateTimeOffset.UtcNow);
         Assert.Throws<ArgumentOutOfRangeException>(() => new AffectedPackageStatus("unsupported", provenance));
     }
+
+    [Theory]
+    [InlineData("Not Impacted", AffectedPackageStatusCatalog.NotAffected)]
+    [InlineData("Resolved", AffectedPackageStatusCatalog.Fixed)]
+    [InlineData("Mitigation provided", AffectedPackageStatusCatalog.Mitigated)]
+    [InlineData("Out of scope", AffectedPackageStatusCatalog.NotApplicable)]
+    public void TryNormalize_ReturnsExpectedValue(string input, string expected)
+    {
+        Assert.True(AffectedPackageStatusCatalog.TryNormalize(input, out var normalized));
+        Assert.Equal(expected, normalized);
+    }
+
+    [Fact]
+    public void TryNormalize_ReturnsFalseForUnknown()
+    {
+        Assert.False(AffectedPackageStatusCatalog.TryNormalize("unsupported", out _));
+    }
+
+    [Fact]
+    public void Allowed_ReturnsCanonicalStatuses()
+    {
+        var expected = new[]
+        {
+            AffectedPackageStatusCatalog.KnownAffected,
+            AffectedPackageStatusCatalog.KnownNotAffected,
+            AffectedPackageStatusCatalog.UnderInvestigation,
+            AffectedPackageStatusCatalog.Fixed,
+            AffectedPackageStatusCatalog.FirstFixed,
+            AffectedPackageStatusCatalog.Mitigated,
+            AffectedPackageStatusCatalog.NotApplicable,
+            AffectedPackageStatusCatalog.Affected,
+            AffectedPackageStatusCatalog.NotAffected,
+            AffectedPackageStatusCatalog.Pending,
+            AffectedPackageStatusCatalog.Unknown,
+        };
+
+        Assert.Equal(expected, AffectedPackageStatusCatalog.Allowed);
+    }
 }

src/StellaOps.Feedser.Models.Tests/SeverityNormalizationTests.cs

@@ -12,6 +12,14 @@ public sealed class SeverityNormalizationTests
     [InlineData("Info", "informational")]
     [InlineData("negligible", "none")]
     [InlineData("unknown", "unknown")]
+    [InlineData("Sev Critical", "critical")]
+    [InlineData("HIGH vendor", "high")]
+    [InlineData("Informative", "informational")]
+    [InlineData("Not Applicable", "none")]
+    [InlineData("Undetermined", "unknown")]
+    [InlineData("Priority 0", "critical")]
+    [InlineData("Priority-2", "medium")]
+    [InlineData("N/A", "none")]
     [InlineData("custom-level", "custom-level")]
     public void Normalize_ReturnsExpectedCanonicalValue(string input, string expected)
     {

src/StellaOps.Feedser.Models.Tests/StellaOps.Feedser.Models.Tests.csproj

@@ -7,4 +7,9 @@
   <ItemGroup>
     <ProjectReference Include="../StellaOps.Feedser.Models/StellaOps.Feedser.Models.csproj" />
   </ItemGroup>
+  <ItemGroup Condition="'$(UpdateGoldens)' == 'true'">
+    <EnvironmentVariables Include="UPDATE_GOLDENS">
+      <Value>1</Value>
+    </EnvironmentVariables>
+  </ItemGroup>
 </Project>

src/StellaOps.Feedser.Models/AffectedPackageStatusCatalog.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
 
 namespace StellaOps.Feedser.Models;
 
@@ -20,7 +21,7 @@ public static class AffectedPackageStatusCatalog
     public const string Pending = "pending";
     public const string Unknown = "unknown";
 
-    private static readonly HashSet<string> AllowedStatuses = new(StringComparer.OrdinalIgnoreCase)
+    private static readonly string[] CanonicalStatuses =
     {
         KnownAffected,
         KnownNotAffected,
@@ -35,21 +36,121 @@ public static class AffectedPackageStatusCatalog
         Unknown,
     };
 
-    public static IReadOnlyCollection<string> Allowed => AllowedStatuses;
+    private static readonly IReadOnlyList<string> AllowedStatuses = Array.AsReadOnly(CanonicalStatuses);
+
+    private static readonly IReadOnlyDictionary<string, string> StatusMap = BuildStatusMap();
+
+    public static IReadOnlyList<string> Allowed => AllowedStatuses;
 
     public static string Normalize(string status)
     {
-        if (string.IsNullOrWhiteSpace(status))
-        {
-            throw new ArgumentException("Status must be provided.", nameof(status));
-        }
-
-        var token = status.Trim().ToLowerInvariant().Replace(' ', '_').Replace('-', '_');
-        if (!AllowedStatuses.Contains(token))
+        if (!TryNormalize(status, out var normalized))
         {
             throw new ArgumentOutOfRangeException(nameof(status), status, "Status is not part of the allowed affected-package status glossary.");
         }
 
-        return token;
+        return normalized;
+    }
+
+    public static bool TryNormalize(string? status, [NotNullWhen(true)] out string? normalized)
+    {
+        normalized = null;
+
+        if (string.IsNullOrWhiteSpace(status))
+        {
+            return false;
+        }
+
+        var token = Sanitize(status);
+        if (token.Length == 0)
+        {
+            return false;
+        }
+
+        if (!StatusMap.TryGetValue(token, out normalized))
+        {
+            return false;
+        }
+
+        return true;
+    }
+
+    public static bool IsAllowed(string? status)
+        => TryNormalize(status, out _);
+
+    private static IReadOnlyDictionary<string, string> BuildStatusMap()
+    {
+        var map = new Dictionary<string, string>(StringComparer.Ordinal);
+        foreach (var status in CanonicalStatuses)
+        {
+            map[Sanitize(status)] = status;
+        }
+
+        Add(map, "known not vulnerable", KnownNotAffected);
+        Add(map, "known unaffected", KnownNotAffected);
+        Add(map, "known not impacted", KnownNotAffected);
+        Add(map, "vulnerable", Affected);
+        Add(map, "impacted", Affected);
+        Add(map, "impacting", Affected);
+        Add(map, "not vulnerable", NotAffected);
+        Add(map, "unaffected", NotAffected);
+        Add(map, "not impacted", NotAffected);
+        Add(map, "no impact", NotAffected);
+        Add(map, "impact free", NotAffected);
+        Add(map, "investigating", UnderInvestigation);
+        Add(map, "analysis in progress", UnderInvestigation);
+        Add(map, "analysis pending", UnderInvestigation);
+        Add(map, "patch available", Fixed);
+        Add(map, "fix available", Fixed);
+        Add(map, "patched", Fixed);
+        Add(map, "resolved", Fixed);
+        Add(map, "remediated", Fixed);
+        Add(map, "workaround available", Mitigated);
+        Add(map, "mitigation available", Mitigated);
+        Add(map, "mitigation provided", Mitigated);
+        Add(map, "not applicable", NotApplicable);
+        Add(map, "n/a", NotApplicable);
+        Add(map, "na", NotApplicable);
+        Add(map, "does not apply", NotApplicable);
+        Add(map, "out of scope", NotApplicable);
+        Add(map, "pending fix", Pending);
+        Add(map, "awaiting fix", Pending);
+        Add(map, "awaiting patch", Pending);
+        Add(map, "scheduled", Pending);
+        Add(map, "planned", Pending);
+        Add(map, "tbd", Unknown);
+        Add(map, "to be determined", Unknown);
+        Add(map, "undetermined", Unknown);
+        Add(map, "not yet known", Unknown);
+
+        return map;
+    }
+
+    private static void Add(IDictionary<string, string> map, string alias, string canonical)
+    {
+        var key = Sanitize(alias);
+        if (key.Length == 0)
+        {
+            return;
+        }
+
+        map[key] = canonical;
+    }
+
+    private static string Sanitize(string value)
+    {
+        var span = value.AsSpan();
+        var buffer = new char[span.Length];
+        var index = 0;
+
+        foreach (var ch in span)
+        {
+            if (char.IsLetterOrDigit(ch))
+            {
+                buffer[index++] = char.ToLowerInvariant(ch);
+            }
+        }
+
+        return index == 0 ? string.Empty : new string(buffer, 0, index);
     }
 }

src/StellaOps.Feedser.Models/SeverityNormalization.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Text;
 
 namespace StellaOps.Feedser.Models;
 
@@ -8,28 +9,76 @@ namespace StellaOps.Feedser.Models;
 /// </summary>
 public static class SeverityNormalization
 {
-    private static readonly IReadOnlyDictionary<string, string> SeverityMap = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
+    private static readonly IReadOnlyDictionary<string, string> SeverityMap = new Dictionary<string, string>
     {
         ["critical"] = "critical",
-        ["sev_critical"] = "critical",
-        ["sev-critical"] = "critical",
+        ["crit"] = "critical",
+        ["sevcritical"] = "critical",
+        ["extreme"] = "critical",
+        ["verycritical"] = "critical",
+        ["veryhigh"] = "critical",
+        ["p0"] = "critical",
+        ["priority0"] = "critical",
         ["high"] = "high",
-        ["sev_high"] = "high",
-        ["sev-high"] = "high",
+        ["sevhigh"] = "high",
         ["important"] = "high",
         ["severe"] = "high",
+        ["major"] = "high",
+        ["urgent"] = "high",
+        ["elevated"] = "high",
+        ["p1"] = "high",
+        ["priority1"] = "high",
         ["medium"] = "medium",
         ["moderate"] = "medium",
         ["normal"] = "medium",
         ["avg"] = "medium",
+        ["average"] = "medium",
+        ["standard"] = "medium",
+        ["p2"] = "medium",
+        ["priority2"] = "medium",
         ["low"] = "low",
         ["minor"] = "low",
-        ["info"] = "informational",
+        ["minimal"] = "low",
+        ["limited"] = "low",
+        ["p3"] = "low",
+        ["priority3"] = "low",
         ["informational"] = "informational",
+        ["info"] = "informational",
+        ["informative"] = "informational",
         ["notice"] = "informational",
+        ["advisory"] = "informational",
         ["none"] = "none",
         ["negligible"] = "none",
+        ["insignificant"] = "none",
+        ["notapplicable"] = "none",
+        ["na"] = "none",
         ["unknown"] = "unknown",
+        ["undetermined"] = "unknown",
+        ["notdefined"] = "unknown",
+        ["notspecified"] = "unknown",
+        ["pending"] = "unknown",
+        ["tbd"] = "unknown",
+    };
+
+    private static readonly char[] TokenSeparators =
+    {
+        ' ',
+        '/',
+        '\\',
+        '-',
+        '_',
+        ',',
+        ';',
+        ':',
+        '(',
+        ')',
+        '[',
+        ']',
+        '{',
+        '}',
+        '|',
+        '+',
+        '&'
     };
 
     public static readonly IReadOnlyCollection<string> CanonicalLevels = new[]
@@ -51,18 +100,53 @@ public static class SeverityNormalization
         }
 
         var trimmed = severity.Trim();
-        if (SeverityMap.TryGetValue(trimmed, out var mapped))
+
+        if (TryNormalizeToken(trimmed, out var mapped))
         {
             return mapped;
         }
 
-        var lowered = trimmed.ToLowerInvariant();
-
-        if (SeverityMap.TryGetValue(lowered, out mapped))
+        foreach (var token in trimmed.Split(TokenSeparators, StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries))
+        {
+            if (TryNormalizeToken(token, out mapped))
             {
                 return mapped;
             }
+        }
 
-        return lowered;
+        return trimmed.ToLowerInvariant();
+    }
+
+    private static bool TryNormalizeToken(string value, out string mapped)
+    {
+        var normalized = NormalizeToken(value);
+        if (normalized.Length == 0)
+        {
+            mapped = string.Empty;
+            return false;
+        }
+
+        if (!SeverityMap.TryGetValue(normalized, out var mappedValue))
+        {
+            mapped = string.Empty;
+            return false;
+        }
+
+        mapped = mappedValue;
+        return true;
+    }
+
+    private static string NormalizeToken(string value)
+    {
+        var builder = new StringBuilder(value.Length);
+        foreach (var ch in value)
+        {
+            if (char.IsLetterOrDigit(ch))
+            {
+                builder.Append(char.ToLowerInvariant(ch));
+            }
+        }
+
+        return builder.ToString();
     }
 }

src/StellaOps.Feedser.Models/TASKS.md

@@ -12,7 +12,7 @@
 |Range primitives for SemVer/EVR/NEVRA metadata|BE-Merge|Models|TODO – keep structured values without parsing logic; ensure merge/export parity.|
 |Provenance envelope field masks|BE-Merge|Models|TODO – guarantee traceability for each mapped field.|
 |Backward-compatibility playbook|BE-Merge, QA|Models|DONE – see `BACKWARD_COMPATIBILITY.md` for evolution policy/test checklist.|
-|Golden canonical examples|QA|Models|DOING – `CanonicalExampleFactory` + tests added; fixtures need regeneration hookup to enable easy updates.|
+|Golden canonical examples|QA|Models|DONE – added `/p:UpdateGoldens=true` test hook wiring `UPDATE_GOLDENS=1` so canonical fixtures regenerate via `dotnet test`; docs/tests unchanged.|
 |Serialization determinism regression tests|QA|Models|TODO – automate hash comparisons across locales/runs.|
-|Severity normalization helpers|BE-Merge|Models|DOING – helper introduced to normalize vendor severities; refine synonym coverage.|
-|AffectedPackage status glossary & guardrails|BE-Merge|Models|DOING – status catalog with validation added; monitor for additional vendor values.|
+|Severity normalization helpers|BE-Merge|Models|DONE – helper now normalizes compound vendor labels/priority tiers with expanded synonym coverage and regression tests.|
+|AffectedPackage status glossary & guardrails|BE-Merge|Models|DONE – catalog now exposes deterministic listing, TryNormalize helpers, and synonym coverage for vendor phrases (not vulnerable, workaround available, etc.).|

src/StellaOps.Feedser.Source.CertIn.Tests/CertIn/Fixtures/expected-advisory.json

@@ -91,7 +91,7 @@
       "url": "https://www.cve.org/CVERecord?id=CVE-2024-9991"
     }
   ],
-  "severity": "high vendor",
+  "severity": "high",
   "summary": "Example Gateway devices vulnerable to remote code execution (CVE-2024-9990).",
   "title": "Multiple vulnerabilities in Example Gateway"
 }

src/StellaOps.Feedser.Storage.Mongo.Tests/ExportStateManagerTests.cs

@@ -22,6 +22,7 @@ public sealed class ExportStateManagerTests
             cursor: "cursor-1",
             targetRepository: "registry.local/json",
             exporterVersion: "1.0.0",
+            resetBaseline: true,
             cancellationToken: CancellationToken.None);
 
         Assert.Equal("export:json", record.Id);
@@ -35,6 +36,93 @@ public sealed class ExportStateManagerTests
         Assert.Equal(timeProvider.Now, record.UpdatedAt);
     }
 
+    [Fact]
+    public async Task StoreFullExport_ResetBaselineOverridesExisting()
+    {
+        var store = new InMemoryExportStateStore();
+        var timeProvider = new TestTimeProvider(DateTimeOffset.Parse("2024-07-20T12:00:00Z"));
+        var manager = new ExportStateManager(store, timeProvider);
+
+        await manager.StoreFullExportAsync(
+            exporterId: "export:json",
+            exportId: "20240720T120000Z",
+            exportDigest: "sha256:base",
+            cursor: "cursor-base",
+            targetRepository: null,
+            exporterVersion: "1.0.0",
+            resetBaseline: true,
+            cancellationToken: CancellationToken.None);
+
+        timeProvider.Advance(TimeSpan.FromMinutes(5));
+        var withoutReset = await manager.StoreFullExportAsync(
+            exporterId: "export:json",
+            exportId: "20240720T120500Z",
+            exportDigest: "sha256:new",
+            cursor: "cursor-new",
+            targetRepository: null,
+            exporterVersion: "1.0.1",
+            resetBaseline: false,
+            cancellationToken: CancellationToken.None);
+
+        Assert.Equal("20240720T120000Z", withoutReset.BaseExportId);
+        Assert.Equal("sha256:base", withoutReset.BaseDigest);
+        Assert.Equal("sha256:new", withoutReset.LastFullDigest);
+        Assert.Equal("cursor-new", withoutReset.ExportCursor);
+        Assert.Equal(timeProvider.Now, withoutReset.UpdatedAt);
+
+        timeProvider.Advance(TimeSpan.FromMinutes(5));
+        var reset = await manager.StoreFullExportAsync(
+            exporterId: "export:json",
+            exportId: "20240720T121000Z",
+            exportDigest: "sha256:final",
+            cursor: "cursor-final",
+            targetRepository: null,
+            exporterVersion: "1.0.2",
+            resetBaseline: true,
+            cancellationToken: CancellationToken.None);
+
+        Assert.Equal("20240720T121000Z", reset.BaseExportId);
+        Assert.Equal("sha256:final", reset.BaseDigest);
+        Assert.Equal("sha256:final", reset.LastFullDigest);
+        Assert.Null(reset.LastDeltaDigest);
+        Assert.Equal("cursor-final", reset.ExportCursor);
+        Assert.Equal(timeProvider.Now, reset.UpdatedAt);
+    }
+
+    [Fact]
+    public async Task StoreFullExport_ResetsBaselineWhenRepositoryChanges()
+    {
+        var store = new InMemoryExportStateStore();
+        var timeProvider = new TestTimeProvider(DateTimeOffset.Parse("2024-07-21T08:00:00Z"));
+        var manager = new ExportStateManager(store, timeProvider);
+
+        await manager.StoreFullExportAsync(
+            exporterId: "export:json",
+            exportId: "20240721T080000Z",
+            exportDigest: "sha256:base",
+            cursor: "cursor-base",
+            targetRepository: "registry/v1/json",
+            exporterVersion: "1.0.0",
+            resetBaseline: true,
+            cancellationToken: CancellationToken.None);
+
+        timeProvider.Advance(TimeSpan.FromMinutes(10));
+        var updated = await manager.StoreFullExportAsync(
+            exporterId: "export:json",
+            exportId: "20240721T081000Z",
+            exportDigest: "sha256:new",
+            cursor: "cursor-new",
+            targetRepository: "registry/v2/json",
+            exporterVersion: "1.1.0",
+            resetBaseline: false,
+            cancellationToken: CancellationToken.None);
+
+        Assert.Equal("20240721T081000Z", updated.BaseExportId);
+        Assert.Equal("sha256:new", updated.BaseDigest);
+        Assert.Equal("sha256:new", updated.LastFullDigest);
+        Assert.Equal("registry/v2/json", updated.TargetRepository);
+    }
+
     [Fact]
     public async Task StoreDeltaExportRequiresBaseline()
     {
@@ -63,6 +151,7 @@ public sealed class ExportStateManagerTests
             cursor: "cursor-1",
             targetRepository: null,
             exporterVersion: "1.0.0",
+            resetBaseline: true,
             cancellationToken: CancellationToken.None);
 
         timeProvider.Advance(TimeSpan.FromMinutes(10));

src/StellaOps.Feedser.Storage.Mongo/Exporting/ExportStateManager.cs

@@ -31,6 +31,7 @@ public sealed class ExportStateManager
         string? cursor,
         string? targetRepository,
         string exporterVersion,
+        bool resetBaseline,
         CancellationToken cancellationToken)
     {
         ArgumentException.ThrowIfNullOrEmpty(exporterId);
@@ -39,36 +40,59 @@ public sealed class ExportStateManager
         ArgumentException.ThrowIfNullOrEmpty(exporterVersion);
 
         var existing = await _store.FindAsync(exporterId, cancellationToken).ConfigureAwait(false);
-        var repository = string.IsNullOrWhiteSpace(targetRepository) ? existing?.TargetRepository : targetRepository;
         var now = _timeProvider.GetUtcNow();
 
-        var baseExportId = existing?.BaseExportId ?? exportId;
-        var baseDigest = existing?.BaseDigest ?? exportDigest;
-
-        var record = existing is null
-            ? new ExportStateRecord(
+        if (existing is null)
+        {
+            var resolvedRepository = string.IsNullOrWhiteSpace(targetRepository) ? null : targetRepository;
+            return await _store.UpsertAsync(
+                new ExportStateRecord(
                     exporterId,
-                baseExportId,
-                baseDigest,
-                exportDigest,
+                    BaseExportId: exportId,
+                    BaseDigest: exportDigest,
+                    LastFullDigest: exportDigest,
                     LastDeltaDigest: null,
                     ExportCursor: cursor ?? exportDigest,
-                TargetRepository: repository,
+                    TargetRepository: resolvedRepository,
                     ExporterVersion: exporterVersion,
-                UpdatedAt: now)
+                    UpdatedAt: now),
+                cancellationToken).ConfigureAwait(false);
+        }
+
+        var repositorySpecified = !string.IsNullOrWhiteSpace(targetRepository);
+        var resolvedRepo = repositorySpecified ? targetRepository : existing.TargetRepository;
+        var repositoryChanged = repositorySpecified
+            && !string.Equals(existing.TargetRepository, targetRepository, StringComparison.Ordinal);
+
+        var shouldResetBaseline =
+            resetBaseline
+            || string.IsNullOrWhiteSpace(existing.BaseExportId)
+            || string.IsNullOrWhiteSpace(existing.BaseDigest)
+            || repositoryChanged;
+
+        var updatedRecord = shouldResetBaseline
+            ? existing with
+            {
+                BaseExportId = exportId,
+                BaseDigest = exportDigest,
+                LastFullDigest = exportDigest,
+                LastDeltaDigest = null,
+                ExportCursor = cursor ?? exportDigest,
+                TargetRepository = resolvedRepo,
+                ExporterVersion = exporterVersion,
+                UpdatedAt = now,
+            }
             : existing with
             {
-                BaseExportId = baseExportId,
-                BaseDigest = baseDigest,
                 LastFullDigest = exportDigest,
                 LastDeltaDigest = null,
                 ExportCursor = cursor ?? existing.ExportCursor,
-                TargetRepository = repository,
+                TargetRepository = resolvedRepo,
                 ExporterVersion = exporterVersion,
                 UpdatedAt = now,
             };
 
-        return await _store.UpsertAsync(record, cancellationToken).ConfigureAwait(false);
+        return await _store.UpsertAsync(updatedRecord, cancellationToken).ConfigureAwait(false);
     }
 
     public async Task<ExportStateRecord> StoreDeltaExportAsync(