Kit

Build me a personal newsletter tool to replace Kit for a small list. Requirements: - Node + Express + better-sqlite3 on my VPS. Subscribers, campaigns, sends, and events all in one SQLite file. - A public /subscribe form with double opt-in: signed confirmation link by email before anyone is added. One-click unsubscribe link in every footer, no login. - Compose campaigns in Markdown in the admin UI (bound to localhost or my VPN only), preview rendered HTML, send to everyone or to a tag. - Sends go through Amazon SES or Postmark (key in .env) at a throttled rate, with per-recipient status recorded; bounce and complaint webhooks auto-suppress bad addresses. - Tags on subscribers, plus one simple welcome autoresponder: a single email sent N minutes after confirmation. - CSV import and export of the list, so I can arrive from Kit and leave anytime. - No accounts beyond mine, no telemetry, no tracking pixels by default. - Out of scope: landing pages, visual automation builders, the creator recommendation network, and commerce. This sends email, nothing else. - README with a blunt warning: deliverability is DNS homework. Walk me through SPF, DKIM, and DMARC before the first send, budget an afternoon for it.