diff --git a/sequencer.c b/sequencer.c
index ffa4334982..894c7538d5 100644
--- a/sequencer.c
+++ b/sequencer.c
@@ -4700,52 +4700,22 @@ int check_todo_list_from_file(struct repository *r)
 	return res;
 }
 
-static int rewrite_file(const char *path, const char *buf, size_t len)
-{
-	int rc = 0;
-	int fd = open(path, O_WRONLY | O_TRUNC);
-	if (fd < 0)
-		return error_errno(_("could not open '%s' for writing"), path);
-	if (write_in_full(fd, buf, len) < 0)
-		rc = error_errno(_("could not write to '%s'"), path);
-	if (close(fd) && !rc)
-		rc = error_errno(_("could not close '%s'"), path);
-	return rc;
-}
-
 /* skip picking commits whose parents are unchanged */
-static int skip_unnecessary_picks(struct repository *r, struct object_id *output_oid)
+static int skip_unnecessary_picks(struct repository *r,
+				  struct todo_list *todo_list,
+				  struct object_id *base_oid)
 {
-	const char *todo_file = rebase_path_todo();
-	struct strbuf buf = STRBUF_INIT;
-	struct todo_list todo_list = TODO_LIST_INIT;
 	struct object_id *parent_oid;
-	int fd, i;
+	int i;
 
-	if (!read_oneliner(&buf, rebase_path_onto(), 0))
-		return error(_("could not read 'onto'"));
-	if (get_oid(buf.buf, output_oid)) {
-		strbuf_release(&buf);
-		return error(_("need a HEAD to fixup"));
-	}
-	strbuf_release(&buf);
-
-	if (strbuf_read_file_or_whine(&todo_list.buf, todo_file) < 0)
-		return -1;
-	if (todo_list_parse_insn_buffer(r, todo_list.buf.buf, &todo_list) < 0) {
-		todo_list_release(&todo_list);
-		return -1;
-	}
-
-	for (i = 0; i < todo_list.nr; i++) {
-		struct todo_item *item = todo_list.items + i;
+	for (i = 0; i < todo_list->nr; i++) {
+		struct todo_item *item = todo_list->items + i;
 
 		if (item->command >= TODO_NOOP)
 			continue;
 		if (item->command != TODO_PICK)
 			break;
 		if (parse_commit(item->commit)) {
-			todo_list_release(&todo_list);
 			return error(_("could not parse commit '%s'"),
 				oid_to_hex(&item->commit->object.oid));
 		}
@@ -4754,42 +4724,26 @@ static int skip_unnecessary_picks(struct repository *r, struct object_id *output
 		if (item->commit->parents->next)
 			break; /* merge commit */
 		parent_oid = &item->commit->parents->item->object.oid;
-		if (!oideq(parent_oid, output_oid))
+		if (!oideq(parent_oid, base_oid))
 			break;
-		oidcpy(output_oid, &item->commit->object.oid);
+		oidcpy(base_oid, &item->commit->object.oid);
 	}
 	if (i > 0) {
-		int offset = get_item_line_offset(&todo_list, i);
 		const char *done_path = rebase_path_done();
 
-		fd = open(done_path, O_CREAT | O_WRONLY | O_APPEND, 0666);
-		if (fd < 0) {
-			error_errno(_("could not open '%s' for writing"),
-				    done_path);
-			todo_list_release(&todo_list);
-			return -1;
-		}
-		if (write_in_full(fd, todo_list.buf.buf, offset) < 0) {
+		if (todo_list_write_to_file(r, todo_list, done_path, NULL, NULL, i, 0)) {
 			error_errno(_("could not write to '%s'"), done_path);
-			todo_list_release(&todo_list);
-			close(fd);
-			return -1;
-		}
-		close(fd);
-
-		if (rewrite_file(rebase_path_todo(), todo_list.buf.buf + offset,
-				 todo_list.buf.len - offset) < 0) {
-			todo_list_release(&todo_list);
 			return -1;
 		}
 
-		todo_list.current = i;
-		if (is_fixup(peek_command(&todo_list, 0)))
-			record_in_rewritten(output_oid, peek_command(&todo_list, 0));
+		MOVE_ARRAY(todo_list->items, todo_list->items + i, todo_list->nr - i);
+		todo_list->nr -= i;
+		todo_list->current = 0;
+
+		if (is_fixup(peek_command(todo_list, 0)))
+			record_in_rewritten(base_oid, peek_command(todo_list, 0));
 	}
 
-	todo_list_release(&todo_list);
-
 	return 0;
 }
 
@@ -4860,6 +4814,11 @@ int complete_action(struct repository *r, struct replay_opts *opts, unsigned fla
 		return -1;
 	}
 
+	if (opts->allow_ff && skip_unnecessary_picks(r, &new_todo, &oid)) {
+		todo_list_release(&new_todo);
+		return error(_("could not skip unnecessary pick commands"));
+	}
+
 	if (todo_list_write_to_file(r, &new_todo, todo_file, NULL, NULL, -1,
 				    flags & ~(TODO_LIST_SHORTEN_IDS))) {
 		todo_list_release(&new_todo);
@@ -4868,9 +4827,6 @@ int complete_action(struct repository *r, struct replay_opts *opts, unsigned fla
 
 	todo_list_release(&new_todo);
 
-	if (opts->allow_ff && skip_unnecessary_picks(r, &oid))
-		return error(_("could not skip unnecessary pick commands"));
-
 	if (checkout_onto(opts, onto_name, oid_to_hex(&oid), orig_head))
 		return -1;