diff --git a/src/parser/grammar_basic.c b/src/parser/grammar_basic.c
index d229549..25d29d1 100644
--- a/src/parser/grammar_basic.c
+++ b/src/parser/grammar_basic.c
@@ -119,9 +119,11 @@ struct ast *parse_pipeline(struct lexer_context *ctx)
         token = PEEK_TOKEN();
     }
 
-    // TODO handle negation (new AST type)
-
     struct ast *left = parse_command(ctx);
+    if (negation)
+    {
+        left = ast_create_neg(negation, left);
+    }
 
     token = PEEK_TOKEN();
     while (token->type == TOKEN_PIPE)