diff --git a/src/dotnet/QuantEngine.Application/Services/DecisionLearningService.cs b/src/dotnet/QuantEngine.Application/Services/DecisionLearningService.cs
new file mode 100644
index 00000000..926e0526
--- /dev/null
+++ b/src/dotnet/QuantEngine.Application/Services/DecisionLearningService.cs
@@ -0,0 +1,101 @@
+using System.Text.Json;
+using QuantEngine.Core.Interfaces;
+
+namespace QuantEngine.Application.Services;
+
+/// <summary>
+/// Canonical application path for recording factor evidence, decisions, and
+/// realized outcomes in the normalized PostgreSQL learning store.
+/// </summary>
+public sealed class DecisionLearningService
+{
+    private readonly INormalizedLearningStore _store;
+
+    public DecisionLearningService(INormalizedLearningStore store) => _store = store;
+
+    public async Task<Guid> RecordDecisionAsync(
+        string decisionKey,
+        DateTimeOffset decidedAt,
+        string instrumentId,
+        string action,
+        string gate,
+        decimal? score,
+        string sourceVersion,
+        IEnumerable<FactorEvidenceInput> factors,
+        object? trace = null,
+        object? provenance = null)
+    {
+        var decisionId = await _store.AppendDecisionAsync(new DecisionEventRecord(
+            decisionKey,
+            decidedAt,
+            instrumentId,
+            action,
+            gate,
+            score,
+            sourceVersion,
+            JsonSerializer.Serialize(trace ?? new { }),
+            JsonSerializer.Serialize(provenance ?? new { })));
+
+        foreach (var factor in factors)
+        {
+            var observationId = await _store.AppendSourceObservationAsync(new SourceObservationRecord(
+                factor.ObservedAt,
+                instrumentId,
+                factor.SourceName,
+                sourceVersion,
+                factor.PayloadJson,
+                factor.ProvenanceJson));
+            var factorObservationId = await _store.AppendFactorObservationAsync(new FactorObservationRecord(
+                observationId,
+                factor.FactorObservationId,
+                factor.FactorId,
+                factor.FactorVersion,
+                factor.ObservedAt,
+                factor.NumericValue,
+                factor.TextValue,
+                factor.Gate,
+                factor.ProvenanceJson));
+            await _store.AppendDecisionFactorEvidenceAsync(decisionId, factorObservationId, factor.Role);
+        }
+
+        return decisionId;
+    }
+
+    public Task RecordOutcomeAsync(
+        Guid decisionId,
+        int horizonDays,
+        DateTimeOffset evaluatedAt,
+        decimal? realizedReturn,
+        decimal? benchmarkReturn,
+        string outcomeClass,
+        string evaluationGate,
+        object? provenance = null)
+    {
+        decimal? excessReturn = realizedReturn.HasValue && benchmarkReturn.HasValue
+            ? realizedReturn.Value - benchmarkReturn.Value
+            : null;
+        return _store.AppendOutcomeAsync(new OutcomeEvaluationRecord(
+            decisionId,
+            horizonDays,
+            evaluatedAt,
+            realizedReturn,
+            benchmarkReturn,
+            excessReturn,
+            outcomeClass,
+            evaluationGate,
+            JsonSerializer.Serialize(provenance ?? new { })));
+    }
+}
+
+public sealed record FactorEvidenceInput(
+    Guid FactorObservationId,
+    string FactorId,
+    string FactorVersion,
+    DateTimeOffset ObservedAt,
+    decimal? NumericValue,
+    string? TextValue,
+    string Gate,
+    string Role,
+    string SourceName,
+    string PayloadJson,
+    string ProvenanceJson);
diff --git a/src/dotnet/QuantEngine.Web/Program.cs b/src/dotnet/QuantEngine.Web/Program.cs
index 194bdd57..19de1372 100644
--- a/src/dotnet/QuantEngine.Web/Program.cs
+++ b/src/dotnet/QuantEngine.Web/Program.cs
@@ -97,6 +97,7 @@ try
     builder.Services.AddScoped<IWorkspaceRepository, WorkspaceRepository>();
     builder.Services.AddScoped<IPostgresqlHistoryStore, PostgresqlHistoryStore>();
     builder.Services.AddScoped<INormalizedLearningStore, NormalizedLearningStore>();
+    builder.Services.AddScoped<DecisionLearningService>();
     builder.Services.AddScoped<IPostgresqlHistorySnapshotReader, PostgresqlHistorySnapshotReader>();
     builder.Services.AddScoped<HistoryIngestionService>();
     builder.Services.AddScoped<ICollectionRepository, CollectionRepository>();