diff --git a/Jellyfin.Plugin.SmartPlaylist/Lisp/Expression.cs b/Jellyfin.Plugin.SmartPlaylist/Lisp/Expression.cs
index a5c3979..7becb79 100644
--- a/Jellyfin.Plugin.SmartPlaylist/Lisp/Expression.cs
+++ b/Jellyfin.Plugin.SmartPlaylist/Lisp/Expression.cs
@@ -157,11 +157,35 @@ namespace Jellyfin.Plugin.SmartPlaylist.Lisp {
             return new List<Expression>();
         }
     }
-    public class String: Scalar<string> {
+    public class String: Scalar<string>, ISortable<String, Boolean> {
         public String(string value) : base(value) {}
         public override string? ToString() {
             return $"\"{base.ToString()}\"";
         }
+        public static Boolean operator <(String a, String b) {
+            return (a.Value().CompareTo(b.Value()) < 0) ? Boolean.TRUE : Boolean.FALSE;
+        }
+        public static Boolean operator >(String a, String b) {
+            return b < a;
+        }
+        public static Boolean operator <=(String a, String b) {
+            return (a.Value().CompareTo(b.Value()) <= 0) ? Boolean.TRUE : Boolean.FALSE;
+        }
+        public static Boolean operator >=(String a, String b) {
+            return b <= a;
+        }
+        public override int GetHashCode() {
+            return base.GetHashCode();
+        }
+        public override bool Equals(object? other) {
+            return base.Equals(other);
+        }
+        public static Boolean operator ==(String a, String b) {
+            return (a._value == b._value) ? Boolean.TRUE : Boolean.FALSE;
+        }
+        public static Boolean operator !=(String a, String b) {
+            return (a._value != b._value) ? Boolean.TRUE : Boolean.FALSE;
+        }
     }
     public class Cons: Expression {
         public Expression Item1;
diff --git a/Jellyfin.Plugin.SmartPlaylist/Lisp/Interpreter.cs b/Jellyfin.Plugin.SmartPlaylist/Lisp/Interpreter.cs
index 8cb7631..1aa7fca 100644
--- a/Jellyfin.Plugin.SmartPlaylist/Lisp/Interpreter.cs
+++ b/Jellyfin.Plugin.SmartPlaylist/Lisp/Interpreter.cs
@@ -127,16 +127,21 @@ namespace Jellyfin.Plugin.SmartPlaylist.Lisp {
             this["/"] = (x) => _agg((Integer a, Integer b) => a / b, x);
             this["%"] = (x) => _agg((Integer a, Integer b) => a % b, x);
 
-            this["="] = (x) => _cmp((Integer a, Integer b) => a == b, x);
-            this["eq?"] = (x) => _cmp((Integer a, Integer b) => a == b, x);
+            this["="] = (x) => _cmp((Atom a, Atom b) => (a == b)? Boolean.TRUE : Boolean.FALSE, x);
+            this["!="] = (x) => _cmp((Atom a, Atom b) => (a != b)? Boolean.TRUE : Boolean.FALSE, x);
             this["<"] = (x) => _cmp((Integer a, Integer b) => a < b, x);
             this["<="] = (x) => _cmp((Integer a, Integer b) => a <= b, x);
             this[">"] = (x) => _cmp((Integer a, Integer b) => a > b, x);
             this[">="] = (x) => _cmp((Integer a, Integer b) => a >= b, x);
-            this["!="] = (x) => _cmp((Integer a, Integer b) => a != b, x);
             this["not"] = (x) => {
                 return (x.First() == Boolean.FALSE) ? Boolean.TRUE : Boolean.FALSE;
             };
+            this["string="] = (x) => _cmp((String a, String b) => a == b, x);
+            this["string!="] = (x) => _cmp((String a, String b) => a != b, x);
+            this["string>"] = (x) => _cmp((String a, String b) => a > b, x);
+            this["string>="] = (x) => _cmp((String a, String b) => a >= b, x);
+            this["string<"] = (x) => _cmp((String a, String b) => a < b, x);
+            this["string<="] = (x) => _cmp((String a, String b) => a <= b, x);
 
 
             this["haskeys"] = _haskeys;