Cloudflare Workers

Workers have no filesystem (so no postboi.config.ts to auto-load) and no ambient process.env. Construct the provider explicitly with the token from the env binding, then read the request’s FormData and hand it to send(). Postboi extracts the special fields and renders the rest into a tidy HTML table.

// src/index.ts
import Postboi from 'postboi'

interface Env {
	POSTBOI_TOKEN: string
}

export default {
	async fetch(request: Request, env: Env): Promise<Response> {
		const url = new URL(request.url)

		if (request.method === 'POST' && url.pathname === '/contact') {
			const mail = new Postboi({ token: env.POSTBOI_TOKEN })
			await mail.send({ body: request.formData(), to: 'team@example.com' })
			return Response.redirect(new URL('/?sent=1', url).toString(), 303)
		}

		return new Response(/* the contact form */)
	},
}

// src/index.ts
import Postboi from 'postboi'

interface Env {
	POSTBOI_TOKEN: string
}

export default {
	async fetch(request: Request, env: Env): Promise<Response> {
		const url = new URL(request.url)

		if (request.method === 'POST' && url.pathname === '/contact') {
			const mail = new Postboi({ token: env.POSTBOI_TOKEN })
			await mail.send({ body: request.formData(), to: 'team@example.com' })
			return Response.redirect(new URL('/?sent=1', url).toString(), 303)
		}

		return new Response(/* the contact form */)
	},
}

Point a multipart/form-data form at /contact. Include hidden _subject and _reply_to fields, and mirror the email into _reply_to with a one-line oninput so replying reaches the sender. Field names use the fieldset→field syntax.

Set the token as a secret (wrangler secret put POSTBOI_TOKEN, or .dev.vars for local dev), and turn on nodejs_compat in wrangler.jsonc. Swap the provider by constructing a different one — see Providers.

Runnable example: examples/cloudflare-workers-provider-postboi.