Vercel projects can now be configured with vercel.toml
A TOML alternative to vercel.json ships for every project, with comments and a flatter structure. You pick one config file, not several.
Vercel now supports vercel.toml as an alternative to vercel.json, the company said on 2 November. Every project can use it today. It carries all the same configuration properties as vercel.json, but TOML allows comments and gives a flatter structure for nested settings like Services and rewrites.
[services.frontend]
root = "frontend/"
[services.backend]
root = "backend/"
entrypoint = "main:app"You still pick one file, not several: Vercel’s own changelog says to use only vercel.toml, vercel.json or vercel.ts, never a mix. The last of those, vercel.ts, is new in the same release, so a project’s configuration can now be written as JSON, TOML or TypeScript.
Why it matters: vercel.json has been the only option for years, and its nested JSON gets hard to read once a project defines multiple Services, rewrites and headers. TOML’s flatter syntax and comments make that config easier to maintain by hand, and vercel.ts opens the door to generating config programmatically. Nothing about existing vercel.json files needs to change.