diff --git a/pila.c b/pila.c
index 94ebca1..3b79acc 100644
--- a/pila.c
+++ b/pila.c
@@ -399,8 +399,6 @@ compile_end_nat(Pila *st)
 		push_val(st, BOX_INTN((u64)st->cur_compw));
 
 	st->compiling = false;
-	st->cur_compw = nil;
-	st->cur_compw_cap = 0;
 }
 
 Str
@@ -484,6 +482,16 @@ find_word_nat(Pila *st)
 	push_val(st, BOX_INTN((u64)w));
 }
 
+void
+immediate_nat(Pila *st)
+{
+	if (st->cur_compw == nil) {
+		signal_error(st, "no word to mark as immediate");
+		return;
+	}
+	st->cur_compw->flags |= WRDF_IMMEDIATE;
+}
+
 void
 branch_nat(Pila *st)
 {
@@ -694,7 +702,9 @@ main(int argc, char **argv)
 		{.name = Sl(">#"), .kind = WORD_NATIVE, .nat = to_number_nat },
 		{.name = Sl("parse-word"), .kind = WORD_NATIVE, .nat = parse_word_nat },
 		{.name = Sl("find-word"), .kind = WORD_NATIVE, .nat = find_word_nat },
+		{.name = Sl("immediate"), .kind = WORD_NATIVE, .nat = immediate_nat },
 		{.name = Sl("call"), .kind = WORD_NATIVE, .nat = call_nat},
+		{.name = Sl("branch"), .kind = WORD_NATIVE, .nat = branch_nat },
 		{.name = Sl("eval"), .kind = WORD_NATIVE, .nat = eval_nat},
 		{.name = Sl("dup"), .kind = WORD_NATIVE, .nat = dup_nat },
 		{.name = Sl("drop"), .kind = WORD_NATIVE, .nat = drop_nat },
@@ -704,12 +714,14 @@ main(int argc, char **argv)
 		{.name = Sl("emit"), .kind = WORD_NATIVE, .nat = emit_nat },
 		{.name = Sl("."), .kind = WORD_NATIVE, .nat = print_nat },
 		{.name = Sl(","), .kind = WORD_NATIVE, .nat = getch_nat },
-		{.name = Sl("branch"), .kind = WORD_NATIVE, .nat = branch_nat },
 	};
 	for (isize i = 0; i < countof(natws); ++i)
 		add_word(&st, &natws[i]);
 
 	eval(&st, Sl(": ' parse-word find-word ;"));
+	/* isolate prelude state */
+	st.cur_compw = nil;
+	st.cur_compw_cap = 0;
 
 	if (argc > 1) {
 		eval(&st, Str_from_c(argv[1]));