# Build fails with `compatibilityVersion: 4` and TypeScript templates added via `addTemplate`
upgrade breaks my build in local and in vercel
3.xpending triageneeds reproduction
[Nuxt 3.6.5] `nuxt build`, fail at Nitro step for "undefined"
3.xpending triage
Nuxt Build Error (RegExp.prototype.exec)
pending triageupstreamneeds reproduction