I received the following error message after installing oxfmt in a repo that:

• had a vite.config.ts
• doesn't use vp nor had oxfmt configured within vite.config.ts

$ oxfmt --write:
Failed to load configuration file.
/[REDACTED]/vite.config.ts
TypeError [ERR_UNKNOWN_FILE_EXTENSION]: Unknown file extension ".ts" for /[REDACTED]/vite.config.ts
Ensure the file has a valid default export of a JSON-serializable configuration object.

$ pnpm --version
10.28.1
$ node --version
v24.13.0
$ pnpm ls oxfmt
...
devDependencies:
oxfmt 0.43.0

Running pnpm exec oxfmt --init fixed the issue.

Doing the following produced a helpful message:

$ mv .oxfmtrc.json .oxfmtrc.json.disabled
$ mv vite.config.ts vite.config.ts.disabled
$ pnpm exec oxfmt tsconfig.json
Finished in 113ms on 1 files using 10 threads.
No config found, using defaults. Please add a config file or try `oxfmt --init` if needed.

While I completely understand that this is likely an edge case, I mainly wanted to submit as a bug for two reasons:

1. others searching for this issue (aka my future self haha)
2. the docs mention pnpm add ..., add scripts, the pnpm run fmt as the only steps required, which to me implied that a config file wasn't necessary!

Anyway, thanks for oxfmt, I'm just starting to use it now but it seems great!