Replace Next.js with Vercel native serverless functions

[marcalexiei]

• Closes Update next.js #108
• Superseds fix: vercel deploy failing due to ts moduleResolution error #107

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next was only used to expose a single webhook endpoint.

This PR removes it entirely in favour of Vercel's zero-config api/ directory convention.

Important

I've read about here: https://vercel.com/docs/functions,
it sounds that they should be enough for the bot use case

[vercel]

@marcalexiei is attempting to deploy a commit to the Changesets Team on Vercel.

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[vercel]

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Project	Deployment	Actions	Updated (UTC)
changesets-bot	Ready	Preview, Comment	May 8, 2026 9:25am

[Andarist]

Deployment fails with:

Warning: Could not identify Next.js version, ensure it is defined as a project dependency.
Error: No Next.js version detected. Make sure your package.json has "next" in either "dependencies" or "devDependencies". Also check your Root Directory setting matches the directory of your package.json file.

[marcalexiei]

Added a vercel.json with a minimal configuration setting "framework": null.

This disables Vercel’s framework auto-detection, which was incorrectly identifying the project as Next.js after the migration to native serverless functions.

If the deployment still fails, check the Vercel dashboard → Project Settings → General → Framework Preset, and change it from “Next.js” to “Other”.

Note

I’m not very familiar with Vercel, so I used Claude to help identify potential causes for the log you shared.

[Andarist]

Hitting curl https://changesets-1q76dtisl-changesets.vercel.app/api/webhook results with this in the deployment logs:

(node:4) Warning: Failed to load the ES module: /var/task/api/webhook.js. Make sure to set "type": "module" in the nearest package.json file or use the .mjs extension.
(Use `node --trace-warnings ...` to show where the warning was created)
(node:4) Warning: Failed to load the ES module: /var/task/api/webhook.js. Make sure to set "type": "module" in the nearest package.json file or use the .mjs extension.
/var/task/api/webhook.js:1
import { createNodeMiddleware, createProbot } from "probot";
^^^^^^

[marcalexiei]

ts files are compiled to ESM but we don't have "type": "module", so probably the runtime is threading them as CJS so they error once they execute the first import.
Let's see if now works!

[Andarist]

I fixed a couple of issues but now I'm running into this:

Error: [@octokit/auth-app] appId option is required
    at Object.createAppAuth (/var/task/node_modules/@octokit/auth-app/dist-node/index.js:492:11)
    at getState (/var/task/node_modules/octokit-auth-probot/dist-node/index.js:188:21)
    at createProbotAuth (/var/task/node_modules/octokit-auth-probot/dist-node/index.js:203:17)
    at new Octokit (/var/task/node_modules/@octokit/core/dist-node/index.js:113:20)
    at new OctokitWithDefaults (/var/task/node_modules/@octokit/core/dist-node/index.js:143:11)
    at new OctokitWithDefaults (/var/task/node_modules/@octokit/core/dist-node/index.js:143:11)
    at new Probot (/var/task/node_modules/probot/lib/probot.js:38:25)
    at createProbot (/var/task/node_modules/probot/lib/create-probot.js:54:12)
    at <anonymous> (/vercel/path0/api/webhook.ts:9:16)
    at ModuleJob.run (node:internal/modules/esm/module_job:343:25)

I guess Vercel no longer shares secrets through process.env in this new setup.

[Andarist]

Actually, that's probably not it - it's just that those secrets are configured only for the production environment. I thiiiink I have enough proof to say this branch is good to go now. I don't have more time to deal with potential broken deployment fallout right now, so I'll have to land it later.