...

compiler/NubLang/Parsing/Parser.cs

@@ -86,6 +86,7 @@ public sealed class Parser
                 {
                     Symbol.Func => ParseFunc(startIndex, exported, null),
                     Symbol.Struct => ParseStruct(startIndex, exported),
+                    Symbol.Let => ParseGlobalVariable(startIndex, exported),
                     _ => throw new ParseException(Diagnostic
                         .Error($"Expected 'func' or 'struct' but found '{keyword.Symbol}'")
                         .WithHelp("Valid definition keywords are 'func' and 'struct'")
@@ -113,6 +114,22 @@ public sealed class Parser
         return definitions;
     }
 
+    private GlobalVariableSyntax ParseGlobalVariable(int startIndex, bool exported)
+    {
+        var name = ExpectIdentifier();
+
+        TypeSyntax? type = null;
+        if (TryExpectSymbol(Symbol.Colon))
+        {
+            type = ParseType();
+        }
+
+        ExpectSymbol(Symbol.Assign);
+        var value = ParseExpression();
+
+        return new GlobalVariableSyntax(GetTokens(startIndex), name.Value, exported, type, value);
+    }
+
     private FuncSignatureSyntax ParseFuncSignature()
     {
         var startIndex = _tokenIndex;