diff --git a/ports/webassembly/wrapper.js b/ports/webassembly/wrapper.js
index 24f4f8a72c..981ade5d80 100644
--- a/ports/webassembly/wrapper.js
+++ b/ports/webassembly/wrapper.js
@@ -56,6 +56,12 @@ var mainProgram = function()
               repl = false;;
           }
       }
+
+      if (process.stdin.isTTY === false) {
+          contents = fs.readFileSync(0, 'utf8');
+          repl = 0;
+      }
+
       mp_js_init(heap_size);
 
       if (repl) {