yikes,

Guard/Server/Sessions/ISessionStore.cs

@@ -0,0 +1,22 @@
+using System.Collections.Generic;
+
+namespace VanadiumGuard.Server.Sessions
+{
+    /// <summary>
+    /// Session persistence. The in-memory implementation is fine for a single instance;
+    /// swap in Redis or a database behind this interface to run more than one.
+    /// </summary>
+    public interface ISessionStore
+    {
+        void Add(GuardSession session);
+
+        GuardSession? Get(string sessionId);
+
+        /// <summary>Looks a session up by the match id the game server knows it as.</summary>
+        GuardSession? GetByGameSession(string gameSessionId);
+
+        void Remove(string sessionId);
+
+        IReadOnlyList<GuardSession> All();
+    }
+}