# Vignette failing to build with no code changes
**URL:** https://travis-ci.community/t/vignette-failing-to-build-with-no-code-changes/9949
**Category:** R
**Created:** [September 19, 2020, 5:20pm UTC](https://travis-ci.community/t/vignette-failing-to-build-with-no-code-changes/9949 "2020-09-19T17:20:17Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@dm13450](https://travis-ci.community/u/dm13450)
#### Post date: [September 19, 2020, 5:20pm UTC](https://travis-ci.community/t/vignette-failing-to-build-with-no-code-changes/9949/1 "2020-09-19T17:20:17Z")
I’m getting the error:
Running ‘texi2dvi’ on ‘dirichletprocess.tex’ failed.
LaTeX errors:
! Undefined control sequence.
l.1168 \ExplSyntaxOn
After a monthly scheduled build, having not pushed any changes to my package or .travis.yml. So I think something has changed in the TeX installation that is used.
Failing build: [https://travis-ci.org/github/dm13450/dirichletprocess/jobs/700188538](https://travis-ci.org/github/dm13450/dirichletprocess/jobs/700188538)
Working build: [https://travis-ci.org/github/dm13450/dirichletprocess/builds/700177807](https://travis-ci.org/github/dm13450/dirichletprocess/builds/700177807)
Any help or pointers is greatly appreciated!
---
### Author:  [@dm13450](https://travis-ci.community/u/dm13450)
#### Post date: [October 14, 2020, 7:06pm UTC](https://travis-ci.community/t/vignette-failing-to-build-with-no-code-changes/9949/2 "2020-10-14T19:06:25Z")
Managed to fix it:
`\usepackage{expl3}`
was needed in my vignette.