@julien-f well spotted. Thanks!
All good now.

@aqua-calc, I have the same issue....
building at commit level a204b6fb3f1236dc5f4519a734c4d5c8f99f9e9c
and I am getting the same error. Cleaned all a did a fresh git pull --ff-only

yarn run v1.22.5
$ node dist/cli.mjs
(node:3448) Warning: To load an ES module, set "type": "module" in the package.json or use the .mjs extension.
(Use node --trace-warnings ... to show where the warning was created)
/root/xen-orchestra/packages/xo-server/dist/xapi/mixins/index.js:2
import _gpu, * as __gpu from "./gpu";
^^^^^^

SyntaxError: Cannot use import statement outside a module
etc...

The yarn build command produces those files (there is something wrong somewhere, why does the build produces index.js when there is the index.mjs?)

So

1. delete /packages/xo-server/dist/xapi/mixins/index.js (rm index.js)
2. delete /packages/xo-server/dist/xapi/mixins/index.js.map (rm index.js.map)
3. remove the import and export statements referencing index.js from file /packages/xo-server/dist/xapi/mixins/index.mjs (nano index.mjs)

and did the same as above for /packages/xo-server/dist/api/index.js
and same for /packages/xo-server/dist/xo-mixins/index.js

And then yarn start and it starts and orchestra is fine as far as I can see.

Not sure if that's the best but it got me going . Hope this helps someone.