diff --git a/src/vim9compile.c b/src/vim9compile.c
index a891006..bb4807e 100644
--- a/src/vim9compile.c
+++ b/src/vim9compile.c
@@ -1495,6 +1495,32 @@
 }
 
 /*
+ * Generate an ISN_LISTAPPEND instruction.  Works like add().
+ * Argument count is already checked.
+ */
+    static int
+generate_LISTAPPEND(cctx_T *cctx)
+{
+    garray_T	*stack = &cctx->ctx_type_stack;
+    type_T	*list_type;
+    type_T	*item_type;
+    type_T	*expected;
+
+    // Caller already checked that list_type is a list.
+    list_type = ((type_T **)stack->ga_data)[stack->ga_len - 2];
+    item_type = ((type_T **)stack->ga_data)[stack->ga_len - 1];
+    expected = list_type->tt_member;
+    if (need_type(item_type, expected, -1, cctx, FALSE, FALSE) == FAIL)
+	return FAIL;
+
+    if (generate_instr(cctx, ISN_LISTAPPEND) == NULL)
+	return FAIL;
+
+    --stack->ga_len;	    // drop the argument
+    return OK;
+}
+
+/*
  * Generate an ISN_DCALL or ISN_UCALL instruction.
  * Return FAIL if the number of arguments is wrong.
  */
@@ -2537,7 +2563,25 @@
 	// builtin function
 	idx = find_internal_func(name);
 	if (idx >= 0)
-	    res = generate_BCALL(cctx, idx, argcount, argcount_init == 1);
+	{
+	    if (STRCMP(name, "add") == 0 && argcount == 2)
+	    {
+		garray_T    *stack = &cctx->ctx_type_stack;
+		type_T	    *type = ((type_T **)stack->ga_data)[
+							    stack->ga_len - 2];
+
+		// TODO: also check for VAR_BLOB
+		if (type->tt_type == VAR_LIST)
+		{
+		    // inline "add(list, item)" so that the type can be checked
+		    res = generate_LISTAPPEND(cctx);
+		    idx = -1;
+		}
+	    }
+
+	    if (idx >= 0)
+		res = generate_BCALL(cctx, idx, argcount, argcount_init == 1);
+	}
 	else
 	    semsg(_(e_unknownfunc), namebuf);
 	goto theend;
@@ -7656,6 +7700,7 @@
 	case ISN_FOR:
 	case ISN_GETITEM:
 	case ISN_JUMP:
+	case ISN_LISTAPPEND:
 	case ISN_LISTINDEX:
 	case ISN_LISTSLICE:
 	case ISN_LOAD: